Atorvastatin effects on proliferation and apoptosis of rat bone marrow-derived endothelial progenitor cells in vitro / 中国组织工程研究

BACKGROUND: Atorvastatin has a cardiovascular protective effect that significantly improves endothelial function and promotes the mobilization,migration,and differentiation of endothelial progenitor cells.However,the screening of atorvastatin concentration for in vitro cell culture is not well documented. OBJECTIVE: To investigate the effects of different concentrations of atorvastatin on rat bone marrow-derived EPCs growth characteristics. METHODS: Bone marrow mononuclear cells from Sprague-Dawley rats were induced in selective culture fluid to culture EPCs. Immunofluorescence staining was used to identify cell surface markers. Harvested EPCs were divided into control group and atorvastatin groups with four different concentrations (0.01, 0.1, 1, and 10 μmol/L) for culture. The growth and proliferation of EPCs were observed under light microscope and MTT assay. Flow cytometry was used to detect apoptosis in EPCs. Nitric oxide and endothelial nitric oxide synthase levels in the culture fluid were measured by nitrate reductase method. RESULTS AND CONCLUSION: The number of cells tended to increase in the control and atorvastatin groups, and it was highest in the 1 μmol/L atorvastatin group. The cell number in the 10 μmol/L atorvastatin group began to decrease at 7 days of culture. Among the five groups, the apoptotic rate of cells was lowest in the 1 μmol/L atorvastatin group and highest in the 10 μmol/L atorvastatin group. The levels of nitric oxide and endothelial nitric oxide synthase were significantly higher in the 0.01, 0.1 and 1.0 μmol/L atorvastatin groups compared with the control group (P < 0.01), but lower in the 10 μmol/L atorvastatin group compare with the other groups (P < 0.01). Overall, atorvastatin can promote the proliferation of endothelial progenitor cells and reduce apoptosis by increasing the production of endothelial nitric oxide synthase and nitric oxide, and 1 μmol/L atorvastatin is most suitable for the EPCs culture.

The role of HO/CO in the spinal nociception transmission and hyperalgesia of rats induced by formalin / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the role of heme oxygenase and carbon monoxide (HO/CO) in the development of spontaneous pain and hyperalgesia of rats induced by formalin injection.</p><p><b>METHODS</b>Zinc protoporphyrin Znpp (the inhibitor of HO) was intrathecally injected to the rats with formalin inflammatory pain. Hemin (the agonist of HO) was intrathecally injected to the normal rats. The weighted pain scores were used to evaluate the degree of pain response. Thermal withdrawal latency and mechanical withdrawal threshold were observed to assess the degree of thermal hyperalgesia and mechanical allodynia.</p><p><b>RESULTS</b>After the intrathecal injection of Znpp, the weighted pain score obviously reduced in a dose-dependent manner compared with the rats with formalin inflammatory pain. Intrathecal injection of Znpp had no obvious effect on thermal withdrawal latency and mechanical withdrawal threshold in injected feet compared with formalin group. But there was a prolongation in a dose-dependent manner in non injected feet. Intrathecal injection of Hemin to normal rats could shorten the thermal withdrawal latency and reduce the mechanical withdrawal threshold on both sides of hindpaws.</p><p><b>CONCLUSION</b>Intrathecal injection of the HO inhibitor produced prominent inhibition to pain related behavior and thermal and mechanical hyperalgesia induced by formalin injection. Intrathecal injection of HO inductor could induce thermal and mechanical hyperalgesia in normal rats. The results indicated that HO/CO took part in the processes of spinal cord nociceptive information transmission and the development of thermal and mechanical hyperalgesia.</p>

Effect of formalin inflammatory pain on expression of HO-1 in spinal cord of rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate whether formalin inflammatory pain can induce the change in heme oxygenase-1 (HO-1) expression in the spinal cord of rats or not and the time course character.</p><p><b>METHODS</b>42 SD rats were divided into 7 groups (n = 6): control formalin 6 h, formalin 12 h, formalin 1 d, formalin 2 d, formalin 3 d and formalin 7 d groups. Rats were subcutaneously injected with 0.2 ml 0.5% formalin into the ventral surface of right hind paw to induce periphery inflammatory pain. The immunohistochemistry was used to observe the expression of HO-1 protein in laminae I - II of the spinal cord dorsal horn and the area around canalis centralis of the I5 spinal segment of rats.</p><p><b>RESULTS</b>There are rare HO-1 immunoreactive cells in the laminae I - II of the dorsal horn and the area around canalis centralis of the I5 spinal segment of rats of control group and HO-1 immunoreactive cells were light in staining degree. Comparing with control group, the numbers of HO-1 immunoreactive cells in the I - II laminae of dorsal horn and area around canalis centralis were increased in the rats at 6 h after formalin injection. The number and staining degree of HO-1 immunoreactive cells were further increased at 12 h and peaked at 1 d after formalin injection. They didn't return to normal level at the 7th day. There were no difference in right and left dorsal horn in the number and staining degree of HO-1 immunoreactive cells at the same time after formalin injection.</p><p><b>CONCLUSION</b>Formalin inflammatory pain induced increased expression of HO-1 in the spinal cord dorsal horn and the area around canalis centralis of rats. At 1 d after injection of formalin, the increased expression of HO-1 was the most obviously.</p>

Division of CA1, CA3 and DG regions of the hippocampus of Wistar rat / 中国应用生理学杂志

<p><b>OBJECTIVE</b>Division of the CA1, CA3 and dentate gyrus (DG) regions of the hippocampus of Wistar rat under the stereomicroscope.</p><p><b>METHODS</b>Twenty-four Wistar rats were randomly assigned to three groups. (1) The brain was sectioned coronally (n = 6). The sections were stained with thionin and the morphology of cells in each region of the hippocampus was observed under microscopy. (2) The hippocampus was dissected out and observed on the whole. Then, the CA1, CA3 and DG regions of the hippocampus were divided. Every region divided was sectioned, and the morphology of cells was observed. (3) Rats with brain ischemia or not were also decapitated and the HSP 70 expressions were observed in CA1, CA3 + DG regions by Western blot and immunohistochemical staining (n = 12).</p><p><b>RESULTS</b>(1) The CA1, CA3 and DG regions of the hippocampus could be clearly observed in coronal section of the brain stained by thionin. (2) Under the stereomicroscope, the CA1 and DG regions of the hippocampus could be separated along the hippocampal fissure between them in ventral surface of the hippocampus. The CA3 and DG regions of the hippocampus could be separated along a fissure between them. The appearance of cells in the sections of the divided CA1, CA3 and DG specimens is consistent with that in the brain coronal sections, respectively. (3) The results of Western blot indicated that the HSP 70 expression of the brain ischemia group was up-regulated significantly in CA3 + DG regions compared with the sham group. However, HSP 70 expression has no significant changes in CA1 region. The above results were consistent with those of the immunohistochemical staining.</p><p><b>CONCLUSION</b>The CA1, CA3 and DG regions of the hippocampus of Wistar rat could be divided under stereomicroscope, and the divided each region was sensible for detection of protein using Western blot.</p>

Effects of nitric oxide on spontaneous pain reaction and neuronal apoptosis in the spinal cord of rats induced by formalin inflammatory pain / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To observe whether formalin inflammatory pain can induce neuron apoptosis in rats spinal cord or not and the effects of nitric oxide on the spontaneous pain reaction and neuron apoptosis in the spinal cord of rats with formalin inflammatory pain.</p><p><b>METHODS</b>Formalin-induced paw licking time was used to reflect the degree of spontaneous pain of rats, and the flow cytometry was used to detecte neuron apoptosis rate of spinal cord.</p><p><b>RESULTS</b>Compared with control group, the apoptosis ratio of spinal neuron was increased in the rats with formalin inflammatory pain, and peaked at 3d after formalin injection. Pre-intrathecal injection of NOS inhibitor L-NAME inhibited the nociceptive behavioural response in double phases induced by fonnrmalin injection and cut down the neuron apoptosis ratio of spinal cord of rats with formalin inflammatory pain. Nociceptive behavioural response and incraesed neuron apoptosis in the spinal cord were induced by intrathecal injection of L-Arg in normal rats.</p><p><b>CONCLUSION</b>The results indicated that formalin inflammatory pain could induce the apoptosis of spinal neurons. The neurons apoptosis was the most significant on the third day after formalin injection. The increased pruduction of NO in spinal cord could promote the transmit of nociceptive information and participate the induction of neuronal apoptosis during the formalin inflammatory pain.</p>

A novel mutation of the PAX6 gene in a Chinese family with aniridia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>The PAX6 gene encodes a transcriptional regulator involved in oculogenesis and other developmental processes such as aniridia, a congenital condition characterized by the underdevelopment of the iris of eyes. The function of the PAX6 gene in these two conditions is still poorly defined. The purpose of this study is to identify the mutation of the PAX6 gene in a Chinese family with aniridia.</p><p><b>METHODS</b>Two aniridia patients collected from the family underwent full ophthalmologic examination. Genomic DNA was prepared from venous leukocytes of the two patients and five healthy individuals in the family, and 100 unrelated healthycontrols. Exons 4-13 and their immediate flanking sequences of the PAX6 gene was analyzed by PCR amplification, direct sequencing, and single-strand conformation polymorphism(SSCP).</p><p><b>RESULTS</b>The sequencing result revealed a novel PAX6 mutation in the two patients. It was a heterozygous mutation (IVS10+1G>A) at the boundary of exon 10 and intron 10. The mutation was also detected by SSCP analysis. It was not detected in the healthy relatives and unrelated controls.</p><p><b>CONCLUSION</b>Aniridia is an autosomal dominant inheritable disease. A novel PAX6 gene mutation has been identified in the Northeastern Chinese family with aniridia. The genetic analysis suggested that this novel mutation in the PAX6 gene is capable of causing the classic aniridia phenotype.</p>

P38 MAPK antisense oligodeoxynucleotide inhibited the brain ischemic tolerance induced by limb ischemic preconditioning / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To better assess the role of p38 MAPK, this project was designed to investigate whether intraventricular injection of antisense oligodeoxynucleotide (As-ODN) directed against the p38 MAPK of pyramidal neurons in hippocampus could affect the brain ischemic tolerance induced by limb ischemic preconditioning (LIP).</p><p><b>METHODS</b>The rat 4-vessel occlusion global cerebral ischemic model was used. Forty-eight male Wistar rats with permanently occlusion of the bilateral vertebral arteries were divided into 8 groups (n=6): sham, LIP, brain ischemic insult, LIP + brain ischemic insult, distilled water + LIP + brain ischemic insult, p38 MAPK As-ODN and p38 MAPK As-ODN + LIP + brain ischemic insult (two doses of 5 nmol/5 microl and 10 nmol/5 microl were used) groups. Thionin staining was used for observing histological changes of the hippocampus.</p><p><b>RESULTS</b>No significant delayed neuronal death (DND) was detected in the CA1 hippocampus of the rats that underwent sham and LIP operation. Brain ischemic insult for 8 min induced obvious DND as represented with the increase in histological grade (HG) and decrease in neuronal density (ND) significantly compared with sham and LIP groups. LIP protected the CA1 hippocampal pyramidal neurons against DND induced by global brain ischemic insult, suggesting the occurrence of brain ischemic tolerance. However, pretreatment with p38 MAPK As-ODN effectively blocked the ischemic tolerance induced by LIP in a dose dependent manner.</p><p><b>CONCLUSION</b>It could be concluded that p38 MAPK plays an important role in the brain ischemic tolerance induced by LIP.</p>

The role of NO resulted from neuronal nitric oxide synthase in the metabotropic glutamate receptor2/3 mediated-brain ischemic tolerance / 中国应用生理学杂志

<p><b>AIM</b>To explore the role of nitric oxide (NO) resulted from nNOS in the mGluR2/3 mediated-brain ischemic tolerance induced by cerebral ischemic preconditioning (CIP), the present study is undertaken to observe the influences of alpha-methyl-(4-tetrazolyl-phenyl) glycine (MTPG), an antagonist of mGluR2/3, on the expression of nNOS during the induction of the brain ischemic tolerance based on confirming the blocking effect of MTPG on the induction of the tolerance.</p><p><b>METHODS</b>Thirty-six Sprague-Dawley rats, whose vertebral arteries were permanently occluded, were randomly divided into sham, CIP, ischemic insult, CIP+ ischemic insult, MTPG+ CIP and MTPG+ CIP+ ischemic insult groups. Thionin staining and immunohistochemistry were used for neuropathological evaluation and assay of nNOS expression in the hippocampal CA1 subregion of the rats.</p><p><b>RESULTS</b>The expression of nNOS showed moderate and extreme up-regulation in the CIP and ischemia groups, respectively, compared to the sham group. The preceded CIP blocked in certain extent the extreme up-regulation of nNOS induced by brain ischemia in CIP + ischemia group. Administration of MTPG via lateral cerebral ventricle 20 min before CIP blocked the up-regulation of nNOS induced by CIP, but had no influence on the pyramidal neuronal survival. While in the MTPG+ CIP+ ischemic insult group, the expression of nNOS was stronger than that in the MTPG + CIP group, and the up-regulation was accompanied with obvious delayed neuronal death. Discussion concerned illustrated that the relative intensive up-regulation of nNOS in this group might be attributed to brain ischemia other than MTPG.</p><p><b>CONCLUSION</b>NO resulted from nNOS participated the induction of mGluR2/3 mediated-brain ischemic tolerance as a downstream molecule of activation of mGluR2/3 during CIP.</p>

Formalin inflammatory pain induced hippocampal neuronal apoptosis of rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate whether formalin inflammatory pain can induce hippocampal neuronal apoptosis of rats or not.</p><p><b>METHODS</b>Rats were subcutaneously injected with 0.2 ml 0.5% formalin into the ventral surface of right hind paw to induce periphery inflammatory pain. The flinches of rats were counted to observe their painful reaction. Flow cytometry was used to assay the ratio of apoptosis of hippocampal neurons. The immunohistochemistry was used to observe the expression of p53 protein in hippocampal subregions.</p><p><b>RESULTS</b>Compared with control group, the apoptotic ratio of hippocampal neurons was significantly increased in rats with inflammatory pain, and formalin inflammatory pain induced upregulation of p53 protein expression in all hippocampal subregions. Both the apoptotic ratio and the p53 protein expression peaked on the third day after the formalin injection. The twice injection of formalin into the hind paws of rats resulted in an enhancement of painful reaction and increase in apoptotic ratio of hippocampal neurons compared with the rats of injection formalin once group.</p><p><b>CONCLUSION</b>Formalin inflammatory pain can induce the hippocampal neuronal apoptosis in rats with a certain time course. Neuronal apoptosis is relevant to the intensity of pain. The up-regulation of p53 protein expression may implicate in the induction of hippocampal neuronal apoptosis in rats with inflammatory pain.</p>

Intrathecal injection of MK-801 inhibited the NOS activity and NO content of hippocampus in rat during the process of formalin-induced inflammatory pain / 中国应用生理学杂志

<p><b>AIM</b>To study the effect of intrathecal injection of MK-801, a NMDA receptor antagonist, on the NOS activity and NO content of hippocampus in rat during the process of formalin-induced inflammatory pain as well as the pain behavior of rat.</p><p><b>METHODS</b>The degree of pain was determined by observing the time of licking and biting the injected paw. NOS expression in the hippocampus was determined by using NADPH-d histochemical staining. NO content of hippocampus was determined by assaying NO3; and NO2.</p><p><b>RESULTS</b>Subcutaneous injection of formalin elicited a characteristic pain behavioural response consisting of licking and biting the injected paw, etc. Intrathecal injection of MK-801 could shorten obviously the time of licking and biting representing pain behavioural response in phase 2. It is suggested that intrathecal injection of MK-801 could block the pain behavioural response induced by formalin (P < 0.05). The number and staining degree of NADPH-d positive neurons in formalin group significantly increased at 12 h after the formalin injection in CA1, CA2-3 and DG of hippocampus compared with control group as well as NO content, however, the number and staining degree of NADPH-d positive neurons in formalin + MK-801 group significantly decreased in contrast to those of formalin 12 h group as well as the NO content (P < 0.01).</p><p><b>CONCLUSION</b>Intrathecal injection of NMDA receptor antagonist MK-801 could inhibit the NOS activity and NO production in hippocampus of rat, which showed the increase of hippocampal NO production was mainly induced by the peripheral nociceptive information input.</p>

Antisense oligodeoxynucleotides of glial glutamate transporter-1 inhibits the neuro-protection of cerebral ischemic preconditioning in rats / 生理学报

The present study was undertaken to investigate the role of glial glutamate transporter-1 (GLT-1) in the brain ischemic tolerance induced by cerebral ischemic preconditioning (CIP) by observing the effect of GLT-1 antisense oligodeoxynucleotides (AS-ODNs) on the neuro-protection of CIP against brain ischemic insult in rats. Wistar rats with permanently occluded bilateral vertebral arteries were randomly assigned to 7 groups: (1) Sham group: the bilateral common carotid arteries (BCCA) were separated, but without occluding the blood flow; (2) CIP group: the BCCA were clamped for 3 min; (3) Brain ischemic insult group: the BCCA were clamped for 8 min; (4) CIP+brain ischemic insult group: 3 min CIP was preformed 2 d prior to 8 min ischemic insult; (5) Double distilled water group: 5 muL double distilled water was injected into the right lateral cerebral ventricle 12 h before, 12 h and 36 h after the BCCA was separated (but without occluding the blood flow), respectively; (6) AS-ODNs group: 5 microL AS-ODNs solution was injected into the right lateral cerebral ventricle 12 h before, 12 h and 36 h after the BCCA was separated (but without occluding the blood flow), respectively. This group was further divided into 9 nmol and 18 nmol subgroups according to the doses of AS-ODNs; (7) AS-ODNs+CIP+brain ischemic insult group: 5 microL AS-ODNs solution was injected into the right lateral cerebral ventricle 12 h before, 12 h and 36 h after CIP, respectively. This group was also further divided into 9 nmol and 18 nmol subgroups according to the doses of AS-ODNs. The other treatments were the same as those in CIP+brain ischemic insult group. The effect of the AS-ODNs on the expression of GLT-1 was assayed by using Western blot analysis. The profile of delayed neuronal death (DND) of pyramidal neurons in the CA1 hippocampus was evaluated by using thionin staining under light microscope by determining the neuronal density (ND) and histological grade (HG). Western blot analysis showed that AS-ODNs injected into the lateral cerebroventricle inhibited the expression of GLT-1 in the CA1 hippocampus in a dose-dependent manner. Neuropathological evaluation showed that there was no apparent DND in sham and CIP groups. Obvious DND of pyramidal neurons was found in brain ischemic insult group, which was represented by an increase in HG and a decrease in ND. CIP effectively protected the pyramidal neurons in the CA1 hippocampus against DND normally induced by ischemic insult, which indicating that CIP induced ischemic tolerance on the pyramidal neurons in the CA1 hippocampus. However, the injection of AS-ODNs into the lateral cerebroventricle blocked the neuro-protection of CIP against DND induced by brain ischemic insult. These results further proved the role of GLT-1 in the brain ischemic tolerance induced by CIP in rats.

Intracerebroventricular administration of adenosine A1 receptor antisense oligodeoxynucleotide inhibites the neuroprotective effect of the cerebral ischemic preconditioning in rats / 中国应用生理学杂志

<p><b>AIM</b>To further explore the role of adenosine A1 receptor in the neuroprotective effect of cerebral ischemic preconditioning, the present study was undertaken to observe the effect of inhibiting expression of adenosine Al receptor with adenosine A1 receptor antisense oligodeoxynucleotide (ARA1 As-ODN) on the neuroprotective effect of cerebral ischemic preconditioning against delayed neuronal death (DND) normally induced by lethal brain ischemia.</p><p><b>METHOD</b>The rat 4-vessel occlusion global cerebral ischemic model was used. Forty-eight male Wistar rats with permanent occlusion of the bilateral vertebral arteries were divided into 8 groups: Sham, CIP, brain ischemic insult, CIP + brain ischemic insult, Distilled water + CIP + brain ischemic insult, ARA1 As-ODN, ARA1 As-ODN +CIP, ARA1 As-ODN+ CIP + brain ischemic insult(two doses of 10 nmol/5 microl and 20 nmol/5 microl were used) groups. ARA1 As-ODN was dissolved in distilled water and injected into the right lateral cerebral ventricle. To illustrate the profile of DND, histological grade (HG) and neuronal density (ND) in the CA1 region of the hippocampus were examined 7 d after the sham operation or the last time of ischemia under thionin staining.</p><p><b>RESULTS</b>The HG and ND in CIP group were similar to those in sham group. Brain ischemic insult induced obvious DND as represented with the increase in HG and decrease in ND significantly (P < 0.05 vs. sham and CIP groups). In CIP + ischemic insult group,no obvious DND was observed,which indicated that CIP protected pyramidal neurons against the ischemic insult.While the administration of ARA1 As-ODN in ARA1 As-ODN + CIP + brain ischemic insult group caused obvious increase in HG and decrease in ND compared with CIP + brain ischemic insult group (P < 0.05) in a dose dependent manner,which indicated that the neuroprotective effect of CIP against DND of hippocampal pyramidal neurons normally induced by ischemic insult was inhibited by the administration of ARA1 As-ODN.</p><p><b>CONCLUSION</b>The results further demonstrate the association of up-regulation of adenosine A1 receptors with the induction of CIP-mediated BIT.</p>

Neural pathway participates in protection of limb ischemic preconditioning against brain injuries induced by ischemia/reperfusion in rats / 中国应用生理学杂志

<p><b>AIM</b>To explore the role of femoral nerves section (FNS) on the protection of limb ischemic preconditioning (LIP) against cerebral ischemia/reperfusion injuries.</p><p><b>METHODS</b>Model of brain ischemia induced by Four-vessel occlusion was used. LIP was performed by clamping the bilateral femoral arteries for 10 min 3 times in a interval of 10 min. Rats with vertebral arteries permanently occluded were divided into sham group, cerebral ischemic group, FNS + cerebral ischemic group, LIP + cerebral ischemic group, FNS + LIP + cerebral ischemic group. The changes of neural density (ND) in the CA1 hippocampus were observed 7d after the sham operation or brain ischemia under thionin staining. The expression of c-Fos in the CA1 hippocampus was measured 6 h after the sham operation or brain ischemia under immunohistochemistry method.</p><p><b>RESULTS</b>Thionin staining revealed that serious neuronal damage was visualized in the CA1 hippocampus in both cerebral ischemic group and FNS + cerebral ischemic group as compared with sham group. LIP attenuated the neuronal damage of the CA1 subfield induced normally by cerebral ischemia/reperfusion, and ND in LIP + cerebral ischemic group was significantly higher than that in cerebral ischemic group (P < 0.01). But obvious neuronal damage of the CA1 subfield was found in FNS+ LIP + cerebral ischemic group, and ND was significantly decreased as compared with LIP + cerebral ischemic group (P < 0.01). These results suggested that the protection of LIP against cerebral ischemia/reperfusion injuries might be cancelled by preceding section of femoral nerve. It was found that there was almost no c-Fos expression in the CA1 hippocampus in sham group. Changes of c-Fos expression in the CA1 subfield in cerebral ischemic group were similar to that in sham group. But in LIP + cerebral ischemic group, c-Fos expression in the CA1 subfield was markedly increased and the number of positive cells and optical density of c-Fos expression were significantly higher than those in sham and cerebral ischemic group. c-Fos expression in the CA1 subfield was again decreased in FNS + LIP + cerebral ischemic group, and the number of positive cells and optical density of c-Fos expression were significantly lower than those in LIP + cerebral ischemic group.</p><p><b>CONCLUSION</b>Neural pathway participated in the protective effect of LIP on brain, and increased c-Fos expression in the CA1 hippocampus by LIP after cerebral ischemia/reperfusion, might be a part of neural pathway by which LIP induced brain ischemic tolerance.</p>

The prior occlusion of bilateral vertebral arteries during producing global cerebral ischemic damage model may play a protective role as preconditioning / 中国应用生理学杂志

<p><b>AIM</b>To study the effect of different intervals between occlusions of vertebral arteries and bilateral common carotid arteries on the Pulsinelli 4-vessel occlusion global cerebral ischemic model, and the features of ischemia of the brainstem and hippocampus induced by occulusion of bilateral common carotid arteries under the condition of occlusion of unilateral vertebral artery.</p><p><b>METHODS</b>Eighty four adult male Wistar rats were divided into 4 groups randomly: control group, bilateral vertebral artery occluding group, global brain ischemic insult group, and unilateral vertebral artery occluding plus bilateral common carotid arteries occluding group. In the global brain ischemic insult group, rats were further divided into 24 h, 48 h, and 72 h interval subgroups according to the interval between the occlusion of the vertebral arteries and bilateral common carotid arteries. The responses including enlarging of pupils and the light reflex during the brain ischemia were observed. The duration of right reflex disappearing, the general state, and the delayed neuronal death (DND) of pyramidal neurons in the CA1 hippocampus of the rats after the brain ischemia were also observed.</p><p><b>RESULTS</b>Among the global brain ischemic insult group, both the responses and DND were more severe in 72 h interval subgroup than those in 24 h and 48 h interval subgroups. There was no significant difference between 24 h and 48 h interval subgroups. When the bilateral common carotid arteries were occluded under the condition of occlusion of unilateral vertebral artery, severe DND was observed in the CA1 hippocampus ipsilateral to the occluding vertebral artery, but no significant DND was observed in the contralateral CA1 hippocampus.</p><p><b>CONCLUSION</b>The results suggested that the prior occlusion of the bilateral vertebral arteries during producing Pulsinelli 4-vessel occlusion global cerebral ischemic model might be a cerebral ischemic preconditioning that could protect to some extent pyramidal neurons of the hippocampus against severe ischemic insult induced by occlusion of bilateral common carotid arteries within 48 h. Moreover, There is ipsilateral predominance of blood perfusion from one side of vertebral artery to the brainstem and hippocampus, although there was Willis artery circle in rats.</p>

Formalin-induced pain enhanced nitric oxide synthase expression and nitric oxide production in the rat hippocampus / 中国应用生理学杂志

<p><b>AIM</b>To observe the changes of nitric oxide synthase (NOS) activity and nitric oxide (NO) content of hippocampus including their time course and region distribution character in rat during the process of formalin-induced inflammatory pain as well as the pain behavior of rat.</p><p><b>METHODS</b>The pain threshold (PT) was determined by radiant heat-induced tail flick test. NOS expression in the hippocampus was determined by using NADPH-d histochemical staining. NO production in hippocampus was determined by assaying NO3- and NO2-.</p><p><b>RESULTS</b>Subcutaneous injection of formalin elicited nociceptive behavioural response and led to decrease in PT of rat. The number and staining degree of NADPH-d positive neurons began to increase at 6 h after the formalin injection in CA1, CA2 - 3 and DG of hippocampus as well as NO content, which increased most obviously at 12 h and returned to control level at 48 h.</p><p><b>CONCLUSION</b>Formalin-induced inflammatory pain could induce the elevation of NOS activity in CA1, CA2 - 3 and DG of hippocampus with a certain time course, which further led to a increase of NO production in hippocampus.</p>

Clinical analyses of etiopathogenisis,symptom and prognostic of spontaneous subarachnoid hemorrhage / 中国基层医药

Objective To explore clinical characteristics of spontaneous subarachnoid hemorrhage(SAM)pa- tients.Methods Etiopathogenisis and clinical manifestations of 167 SAIl patients of different ages and cause of 24 SAH patients' exacerbation and death were retrospectively analyzed.Results The aneurysm was the main etiologies of SAH.The youth and middle-ages SAH patients were caused by aneurysm.Hypertensive arteriosclerosis was the second etiologies of SAH which was mainly in middle-ages and old ages.SAH caused by Vascular malformation main- ly appeared in youth group.Headache and vomitus and meningeal irritation sign which mainly appeared in youth and middle-ages groups.Occiput pain and conscious disturbance was mainly the first symptoms of aggravation and death of SAH which happened in 14 days after hemorrhage and under 45 year ages.Conclusion Aneurysm and vascular malformations are the main causes of SAH of young patients.And hypertensive arteriosclerosis is the main cause of the old.The clinical manifestations of the old are not as typical as the young.Posterior cranial fossa hemorrhage is the main cause of SAH patients which are mostly under 45 year ages and mostly happen in 14 days after bleeding.

The effect of time parameters of cerebral ischemic preconditioning on its protective effect against global cerebral ischemic injury in rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the effects of the duration of cerebral ischemic preconditioning(CIP) and interval between CIP and the subsequent ischemic insult on the protection of CIP against delayed neuronal death (DND) in the CA1 hippocampus normally induced by brain ischemic insult.</p><p><b>METHODS</b>Four-vessel occlusion cerebral ischemic model of rats (54) was used. The brain of the rats was sectioned and stained with thionin to show DND in the CA1 hippocampus.</p><p><b>RESULTS</b>No DND was found in the hippocampus of the rats subjected to sham operation and CIP, in which 3 min cerebral ischemic preconditioning was performed. Obvious destruction of the CA1 hippocampus was found in brain ischemic insult group, in which histological (HG) was 2-3 in 6 min and 10 min ischemia subgroups and grade 3 in 15 min ischemia subgroup. In CIP + brain ischemic insult group, no obvious neuronal damage was found in 3 min-3d-6 min (CIP for 3 min was followed by a brain ischemic insult for 6 min at an interval of 3 d, the same as the following) and 3 min-3 d-10 min groups, indicating that CIP effectively protected neurons of the CA1 hippocampus against DND normally induced by ischemic insult for 6 or 10 min. However, in 3 min-1 d-10 min and 3 min-3 d-15 min groups, the protective effect of CIP was lower than that in the 3 min-3 d-10 min group. The quantitative analysis of the protective effect of CIP on the CA1 hippocampal neurons showed that there was no significant difference in protecting number and protecting index between 3 min-3 d-6 min and 3 min-3 d-10 min groups (P > 0.05). However, the growth index in 3 min-3 d-10 min group was obvious larger than that in 3 min-3 d-6 min (P < 0.05).</p><p><b>CONCLUSION</b>Although the protective effects of CIP in 3 min-3 d-6 min and 3 min-3 d-10 min groups were similar, the protective effect of CIP in 3 min-3 d-10 min group was sensitively found. Maximal protective potential of CIP could be induced when using the time parameters of 3 min-3 d-10 min to establish the model of global cerebral ischemic tolerance.</p>

Protein kinase C agonist phorbol 12-Myristate-Acetate induces nociception and enhances nitric oxide production in the spinal cord of rats / 中国应用生理学杂志

<p><b>AIM</b>To determine the involvement of NO signal pathway in the development of hyperalgesia induced by activation of protein kinase C (PKC ), nociceptive responses and nitric oxide synthase(NOS) expression and nitric oxide (NO) content in the spinal cord were observed after administration of Phorbol 12-Myristate-Acetate (PMA), a PKC agonist, in rats.</p><p><b>METHODS</b>Nociceptive response was observed by behavioral approach. Pain threshold was assayed using thermal tail-flick test. NADPH-d histochemistry was used to investigate the changes of NOS expression. Nitrate/nitrite (NO3-/NO2-) was assayed to represent NO content of lumbar enlargement of spinal cord.</p><p><b>RESULTS</b>Nociceptive response was induced and pain threshold decreased after intrathecal injection of PMA. The number of NADPH-d positive cells increased significantly in the superficial layer of the spinal cord dorsal horn (Laminae I - II ) and the grey matter surrounding the central canal (Laminae X), and the reactive degree of NADPH-d positive soma and processes and NO content of the lumbar enlargement of the spinal cord increased significantly after intrathecal injection of PMA. Pretreatment of PKC inhibitor chelerythrine chloride blocked the changes induced by PMA.</p><p><b>CONCLUSION</b>The activation of PKC in the spinal cord neurons might induce spontaneous nociceptive responses and hyperalgesia in rats, as well as promote NOS expression and NO production, suggesting that increase in NO production is one of mechanisms of hyperalgesia induced by activation of PKC.</p>

Limb ischemic preconditioning attenuates apoptosis of pyramidal neurons in the CA1 hippocampus induced by cerebral ischemia-reperfusion in rats / 生理学报

The purpose of this study was to investigate the effects of limb ischemic preconditioning (LIP) on apoptosis of pyramidal neurons in the CA1 hippocampus induced by global cerebral ischemia-reperfusion in rats. Forty-six rats whose bilateral vertebral arteries were occluded permanently were assigned to one of four groups: sham group, limb ischemia group, cerebral ischemia group and LIP group. LIP was performed by occluding the bilateral femoral arteries for 10 min 3 times in an interval of 10 min. Global cerebral ischemia was underwent by occluding the bilateral common carotid arteries for 8 min immediately after LIP. Assays for apoptosis of the hippocampal neurons were biologically and morphologically performed using gel electrophoresis, TUNEL and AO/EB staining. Characteristic DNA ladder was clearly visualized with gel electrophoresis in the hippocampus in cerebral ischemia group, but not in LIP group. The number of TUNEL-positive cells in the CA1 hippocampus was significantly reduced by LIP from 69.8+/-12 (cerebral ischemia group) to 17.8+/-5.8 (P<0.01). AO/EB staining also showed a reduction of apoptosis in LIP group compared with cerebral ischemia group. These results suggest that LIP can inhibit hippocampal neuronal apoptosis induced by cerebral ischemia-reperfusion, which contributes to the protection against the delayed neuronal death induced by cerebral ischemic insult.

MK-801 inhibits formalin-induced cyclooxygenase-2 expression in the dorsal horn of the spinal cord in rats / 生理学报

To investigate the effect of N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 on the formalin-induced cyclooxygenase-2 (COX-2) expression in the dorsal horn of the rat spinal cord. Forty-eight male Sprague-Dawley rats were divided into 4 groups: control, formalin, formalin+normal saline (NS) and formalin+MK-801 groups. Rats in formalin, formalin+NS and formalin+MK-801 groups were subcutaneously injected with 0.2 ml 5% formalin into the plantar surface of the right hind paw. NS or MK-801 solution (10 microl) was intrathecally injected under transient ether anesthesia 15 min prior to the formalin injection in the formalin+NS and formalin+MK-801 groups, respectively. Flinch reflex was measured within 1 h after the formalin injection and expression of COX-2 in the dorsal horn of the L(5) segment of the spinal cord was assayed 24 h after the formalin injection using immunohistochemistry. Formalin evoked a biphasic flinch reflex. MK-801 produced a limited effect on the flinch reflex of phase 1, but produced significant and dose-dependent suppression on the flinch reflex of phase 2. The number and immunostaining density, shown by grey degree which was inversely proportional to the immunostaining density, of immunoreactive soma in the superficial (mainly I-II) and deep (IV-VI) laminae of the L(5) spinal cord in formalin and formalin+NS groups increased significantly, in contrast to those in the control group (p<0.01). The number and immunostaining density of immunoreactive soma decreased significantly in formalin+MK-801 group, in comparison with the formalin+NS group (p<0.05). The degree of the decrease was proportional to the dosage of MK-801 used. In addition, there were some immunoreactive processes especially in the superficial laminae, which extended as a continuous band across the dorsal horn after the formalin injection. Change in immunostaining density of the processes after administration of MK-801 was similar to that in the immunoreactive soma. The results showed that intrathecal injection of MK-801 significantly inhibited the increase of COX-2 expression in the spinal dorsal horn induced by the formalin injection in a dose-dependent manner, suggesting that the activation of NMDA receptor is one of the mechanisms for the formalin-induced increase of COX-2 expression in the spinal dorsal horn.