Changes of the nitric oxide synthase-positive and nestin-positive neurons in the basal forebrain of castrated adult male rats following androgen replacement therapy / 中国组织工程研究

BACKGROUND: The neurons in the medial septum (MS), vertical and horizontal limbs of diagonal band of Broca (vDB and hDB) in the basal forebrain contain rich androgen receptors (ARs) and estrogen receptors (ERs) by which androgen and estrogen can act dramatically on the neurons in the basal forebrain, subsequently affecting learning and memory processes.OBJECTIVE: To qualitatively and quantitatively investigate the effects of androgen replacement therapy on the nitric oxide synthase (NOS)-positive and nestin-positive neurons in the MS, vDB and hDB of castrated adult male rats.DESIGN: A randomly controlled study on experimental animals.SETTING: Department of Anatomy and Brain Research Laboratory of Zhngshan Medical College of Sun Yat-sen University.MATERIALS: The experiment was performed at Department of Anatomy and Brain Research Laboratory of Zhongshan Medical College of Sun Yatsen University from June 2001 to June 2002. Totally twenty-eight adult male Sprague-Dawley rats were randomly divided into four groups with seven rats in each group: androgen replacement therapy for 4 weeks following 24 hours of castration (ART1), androgen replacement therapy for 2 weeks following 2 weeks of castration (ART2), vehicle replacement therapy for 4weeks following 24 hours of castration (VRT), sham-operated group (Sham).INTERVENTIONS: ① ART1 group: The castrated rats received subcutaneous injection of testosterone proprionate (25 mg/kg) dissolved in 100 μL of sterile sesame oil every other day from 10:30 am to 11:00 am for 14 times (4 weeks). ② ART2 group: The castrated rats received subcutaneous injection of testosterone proprionate with the same dosage and method as ART1 group for 7 times (2 weeks). ③ The rats in VRT group received subcutaneous injection of 100μL of sterile sesame oil for 14 times (4 weeks) by the same regime as described above. ④ Rats in Sham group only received sham-operated treatments, and testes were intact and lived for 4 weeks.MAIN OUTCOME MEASURES: Morphology and counts of NOS-positive and nestin-positive neurons were observed in the MS, vDB and hDB with immunohistochemical method at various time points.RESULTS: Data of totally 28 rats were involved in the final analyses. ①Morphological features of both NOS-positive and nestin-positive neurons in the MS, vDB and hDB were not significantly changed among four groups. ② The number of NOS-positive and nestin-positive neurons in the MS and vDB of VRT group were significantly higher than those of Sham group (P＜ 0.05 or 0.01), whereas the numbers of the NOS-positive and nestin-posi-tive neurons in the MS and vDB of ART1 and ART2 groups was significantly lower than those of VRT group (P ＜ 0.05 or 0.01), which nearly reached the levels of sham group (P ＞ 0.05).CONCLUSION: Androgen replacement therapy produces no significant effects on the morphological features of NOS-positive and nestin-positive neurons, but the therapy can selectively decrease the numbers of NOS-positive and nestin-positive neurons in different subregions of the basal forebrain, which may be closely related to androgen downregulation of expressions of NOS and nestin by ARs-mediated mechanisms, thereby producing complex effects on learning and memory processes.

Experimental basis for antioxidants TA99 series in the treatment of Alzheimer disease / 中国组织工程研究

OBJECTIVE: In recent years, available evidence from basic and clinical research on Alzheimer disease(AD) suggests that oxidation stress is involved in the occurrence and development of AD, and that antioxidant treatment can improve the intelligence of patients with AD and delay age-dependant cognitive dysfunction. Although results of basic and clinical research on the therapeutic effects of antioxidants on AD are inconsistent, a large number of available data suggest that these studies are of significance. Basic pharmacological studies on natural antioxidant TA99 series indicate that they are promising novel drugs for AD. Thereby, this study made a review of their experimental basis in the treatment of AD and existing problems.DATA SOURCES: Related articles published between January 1991 and December 2004 were searched by the computer in Medline database with such key words as Alzheimer disease, antioxidant, Ginkgo biloba extract, TA9901,acetylcholine, and senescence-accelerated mouse in different combinations and with the language limited to English. Meanwhile, related articles were alsosearched in CDMA \Wanfang database with the same key words in Chinese.STUDY SELECTION: Literature involving intervention group and control group were screened in the first trial, and then non-randomized trials were excluded and the rest were searched for the full text.DATA EXTRACTION: Of the 24 basic and clinical randomized and non-randomized trials on antioxidants in the treatment of AD collected, 17 accorded with the inclusion criteria and the other 7 were excluded.DATA SYNTHESIS: Intervention in the 17 trials emphasized the pathogenesis of AD from amyloid β proterin(Aβ) synthesis, gathering to senile plaque formation, and the enhancement of Aβ gathering and neuronal apoptosis by peroxidative injuries of free radicals. Both in vitro and in vivo studies were conducted: the effect of Aβ on neurons of different regions was observed with cell culture; transmission electromicroscope and sulfrin T (Th-T) fluorescence assay, Fuliye-transform infrared(FT-IR) spectrum apparatus, electron magnetic resonance(EPR), and round spectrum were used to detect the inhibitory effect of TA99 series on Aβ gathering and fibroplasia in vitro, as well as the influence on Aβ gathering in vivo. Senescence accelerated mouse (SAM) -P/8 was adopted to establish AD model and behavioral studies such as Morris water maze were used to investigate their effect on learning and memory. Meanwhile, the clearance of intracerebral amyloid granular deposition due to TA99 was also observed with hexamic argent staining. The effects of TA series on Aβ target and possible mechanism were fully revealed, and basic pre-clinical data collection was almost completed.CONCLUSION: TA9901 plant extractions have been proved to inhibit Aβ gathering and fibrosis, and improve learning and memory of SAM-P/8 rats. Moreover, TA9902 prepared by TA9901 combined with EGb761, another synergic herb, has an obvious anti-neurotoxic effect by inhibiting Aβ gathering, fibrosis and secondary structural changes. Further pharmacological research is needed and will have a promising prospect.

Protective effect of amyloid-beta 42 protein and its subunit vaccines immunization on spatial learning and memory of APPSWE transgenic mice / 中国组织工程研究

BACKGROUND: It has been demonstrated that amyloid-beta 42 protein (Aβ42) immunization in transgenic mouse models of Alzheimer disease(AD)can induce specific Aβ42 antibody, clear Aβ from the brain, and thereby improve spatial learning and memory. It has been a promising treatment strategy for AD.OBJECTIVE: To explore the effect of Aβ42 and its subunit vaccines immunization on spatial learning and memory of APPSWE transgenic mice.DESIGN: A randomized controlled experiment with mice as subjects.SETTING: The brain research laboratory of the anatomy department in a the medical college of a univeristy.MATERIALS: The experiment was conducted in the Experimental Animal Center and the Anatomy Department of Sun Yat-sen University from April 2003 to February 2004. Thirty-two APPSWE transgenic mice of 5 months old were bought from Taconic Company, USA. The second generation of mice were successfully reproduced in the Anatomy Department. These mice were randomly assigned into four groups: control group, Aβ42 group, Aβ1-15group, and Aβ36-42 group. Each group contained 8 in each group.INTERVENTIONS: Aβ42 and its subunits combined with MF59 adjuvant were subcutaneously injected for fundamental immunity and then applied in nasal mucosa for intensified immunization. The immunization period was 8 months. Y-maze was used for behavior test before immunization and Morris water maze was used after immunization.MAIN OUTCOME MEASURES: Spatial learning and memory, mean escape latency, times of passing through the platform point, swimming distance percentage of the first quadrant, and swimming distance percentage of the 20% marginal area.RESULTS: The correct reaction times in Y-maze behavior test were 7.50 ±0. 81, 7.06 ±0.71, 7.19 ±0.91, and 7.50 ±0.86 respectively in the control, Aβ42, Aβ1-15, Aβ36-42 groups and there was no significant difference ( P ＞ 0. 05) . After immunization, the mean escape latencies in 8 units of localized navigation test were(67.3 ±2. 8) s, (23.6 ± 1.6) s, (26.4 ±2.0) s,and (36.5 ± 2.2) s. The results in three experiment groups were different from that in control group and there was no difference between the three experiment groups ( P ＞ 0. 05 ) . The mean times of passing through the platform point in the 4 groups were 0.71 ±0.29, 8.14 ± 1.37, 7.28 ± 1.34,and 3.29 ± 0. 67. Swimming distance percentage of the first quadrant in the4 groups were(24.3 ±2.9)%, (50.6±11.6)%, (49.9±9.3) %,and(35.4±7.0)% and the swimming distance percentages of 20%marginal area were (46.4 ± 7.3 ) %, ( 11.6 ± 3.9) %, ( 14.4 ± 2. 6) %, and (25.8 ± 3.3)%. The mice in three experiment groups showed increase in the times of passing through platform point, swimming distance percentage of the first quadrant, and decrease in distance percentage of 20% marginal area compared with control group. The results in three experiment groups were no significantly different( P ＜ 0. 05).CONCLUSION: Immunization with A342 and its subunits can effectively ameliorate impairment of spatial learning and memory in APPSWE transgenic mice.

Aβ5～35 and Apo E4 enhance neuronal intracellular free Ca2+ / 中国药理学通报

AIM　To study the effects of Aβ25～35 and Apo E4 on neuronal intracellular free Ca2+(［Ca2+］i). METHODS　Hippocampal and cortical neurons suspension of newborn(0～3 days) SD rats was produced. After incubated with fura-2/AM,the neurons suspension was divided into four groups: control, Aβ25～35, Apo E4, Aβ25～35+Apo E4. Each groups ［Ca2+］i was measured using a RF-5000 dual wavelength spectrofluorometer after incubated with double distilled water, Aβ25～35, Apo E4, Aβ25～35+Apo E4 for 3 min, respectively. The neurons outocorrelation function(ACF) of the scattering light intersity was analyzed by the microscope quasi-elastic light scattering(MQLS) technique The frequency shift line width by ACF. The Γ can sympolize the cell menbrane flilidity. RESULTS　Both Aβ25～35 and Apo E4 could significantly enhance hippocampal and cortical neurons rest ［Ca2+］i, furthermore, the effect of 5 μmol*L-1 Aβ25～35 was higher than the effect of 1 μmol*L-1 Aβ25～35 (P<0.05), and they also amplified KCl-induced rise in ［Ca2+］i in hippocampal and cortical neurons(P<0.05). The interaction of Aβ25～35 and Apo E4 could also significantly enhance hippocampal and cortical neurons rest ［Ca2+］i andamplified KCl-induced rise in ［Ca2+］i in hippocampal and cortical neurons(P<0.05), but they had no synergic or additive effect.The frequency shift line widith Γ of both hippocampal and cortical neurons were decreased by both Aβ25-35 and ApoE4. CONCLUSION　Aβ25～35 and Apo E4 could enhance neuronal intracellular free Ca2+, amd decrease meirpma; ,e,brame f;iodotu. But their interaction had no synergic or additive effect. It suggested that the amplified effect of Aβ25～35 and Apo E4 on neuronal ［Ca2+］i and membane fluidity may be relative to their neurotoxity.

An experimental exploration of focal inflammatory response in cerebral ischemic foci in the rat / 中国病理生理杂志

AIM： To study the pathological relationship of vascular cell adhesion molecule-1 (VCAM-1) expression and monocyte/macrophage infiltration with focal brain ischemia. METHODS: Immunohistochemical technique and focal brain ischemia/reperfusion model were used in the study in order to explore profiles and time-course of VCAM-1 expression and monocyte macrophage (ED2 positive cell) infiltration in ischemic rat brain. RESULTS: VCAM-1 was up-regulated in microvascular endothelial cells in ischemic cortex at 1h postischemia, and continuously expressed during the time of reperfusion. ED2 positive cells infiltrated into ischemic cortex at 1h iscehmia/ 2h reperfusion and then ED2 positive cells increased gradually with the time of reperfusion, ED2 positive cell infiltration showed apparently relationship with VCAM-1 expression, and both of them exhibited the some changes of time-dependence. CONCLUSION: Cerebral ischemia induced VCAM-1 expression and ED2 positive cell infiltration and VCAM-1 may regulate the recruitment of ED2 positive cells in the ischemic brain region. The results suggested that VCAM-1 and ED2 positive cells may be participated in the pathogenesis of cerebral ischemic injury.

EFFECT OF bFGF ON THE PROLIFERATION AND DIFFERENTIATION OF THE NEURAL PROGENITOR OF EMBRYONIC HIPPOCAMPUS OF RATS IN VITRO / 神经解剖学杂志

In order to investigate effect of basic fibroblast growth factor(bFGF) on the prolifiration and differentiation of theneural progenitor of embryonic hippocampus of rats in vitro, 25 ng/ml bFGF was employed into the serum-free medium of cultureof hippocampal neural cells of embryonic day 18 rats in the present study. The effect of bFGF on the viability of cells culturedwas detected by MTT colorimetric method and the effects of bFGF on proliferation and differentiation of hippocampal neural pro-genitors were analyzed qualitatively and quantitatively by means of immunochemistry, for the nestin, neurofilament, galactocere-broside and glial acidic fibrillary protein. The results showed that the OD value of experimental group was higher than that ofcontrol group by 1.5 and 1.8 times at 4 d and 8 d respectively. The quantitative analysis of each kinds of cells indicated that thenumber of neural progenitors, neurons and oligodendrocytes in experimental group were increased about 2 times as many as thatin control group, but no differences of astrocytes between the two groups at 4 d. However, the number of four kinds of cells aug-mented about 1.7 times at 8 d. The results of this study suggest that bFGF can not only promote the survival, proliferation, butalso facilitate the differentiation of neural progenitor of hippocampus to neurons and glial cells. To obtain more many purifiedneural progenitors in vitro, the embryonic day 18 is not an appropriate age. It is better to get younger embryo brain to culture and to add enough bFGF.

CONSTRUCTION AND IDENTIFICATION OF RECOMBINANT RETROVIRAL VECTOR CARRYING RAT GDNF GENE / 神经解剖学杂志

Through genetic recombination technique, the rat glial cell line-derived neurotrophic factor (rGDNF) cDNA was in-serted into polylinker site of retroviral vector pLXSN, to generate a recombinant plasmid pLXSN-GDNF as transfer vector. Therecombinant plasmid was verified with restriction analysis, PCR, dot blot hybridization and Southern blot hybridization. The re-sults showed that GDNF cDNA was cloned correctly into retroviral vector pLXSN, recombinant retroviral vector was construct-ed. It is concluded that the eukaryotic cell expression vector was constructed successfully for gene therapy of Parkinson's,Alzheimer's and other central nervous system diseases.

Ginkgo biloba extract enhances c-jun expression and attenuates motoneuron death induced by root avulsion / 中国病理生理杂志

AIM: To investigate the influence of Ginkgo biloba extract (EGb761) on c-jun expressions and motoneurons survival following root avulsion. METHODS: One hundred and eighty adult Sprague-Dawley female rats were randomly divided into control and EGb761 groups. Immediately after avulsion of C5-T1 nerve roots, the rats were injected ip with either 1 mL of EGb761 25 mg?kg~(-1)?d~(-1) or the same volume of normal saline, and the treatment repeated everyday. At 4 h to 6 weeks following avulsion, the C7 spinal segments of all rats were collected and prepared for c-jun immunocytochemistry and neutral red stain. The numbers of (c-jun) positive and survival motoneurons were counted and compared between two groups at each time point. RESULTS: In control rats following avulsion, c-jun positive motoneurons appeared at 4 h, reached its maximum at 1 d and declined to 2 weeks. Avulsion-induced motoneurons death started at 2 weeks, climbed to its maximum at 4 weeks-6 weeks. In EGb761 treated rats, both numbers of c-jun positive and survival motoneurons were more than that in control group at each time point. CONCLUSION: EGb761 attenuates avulsion-induced motoneurons death, and this effect may be related to up-regulation of c-jun gene in avulsed motoneurons. [

Effect of antioxidants TA9901 on the fibril formation of A?_(1-40) injected into cerebral cortex of rat brain / 中国病理生理杂志

AIM: To clarify if TA9901, a natural antioxidants, could inhibit the formation of ?-amyloid(A?) fibril when A? 1-40 were injected into cerebral cortex of rat brain, and explore the mechanism of action of TA9901 on Alzheimer disesse. METHODS: Twelve Wistar rats (250-300 g) were randomly divided into four groups ( n=3 ). (1) control group; (2) TA9901 treatment group (ip. 100 mg?kg -1 ?d -1 ); (3) Vitamin E(VE) treatment group (ip. 100 mg?kg -1 ?d -1 ); (4) PBS group. 5 ?L 0.2% A? 1-40 was immediately injected into the right side of the deep cerebral cortex of control, TA9901 and VE group rats. The animals were sacrificed at the seventh day after the injection. The sections of the rat brain that contained the injected field were examined with transmission electron microscopy and Congo red staining with polarized microscopy. RESULTS: Many depositions of high electron density were observed by electron microscopy in the field where A? 1-40 was injected. They are intimately intermingled with macrophages and astrocytes. In the field, about 10nm fibrillar structures were observed that appeared similar to the fibrils seen in senile plaque (SP) of the brain of Alzheimer disease (AD). The fields in control and VE group contained richer A? fibrils than that in TA9901 group. After the sections stained with Congo red, A? 1-40 aggregation demonstrated intense birefringence under, indication the formation of amyloid fibrils. In TA9901 group, there was a weak birefringence.CONCLUSIONS: TA9901 can inhibit the fibril formation of A? that was injected into deep cerebral cortex of rat brain, this indicates primarily that TA9901 may be a potential therapeutic drug to interfere with the progression of amyloidgenesis in AD.

Influence of Ginkgo biloba extract on NOS expression and survival of C7 motoneurons following brachial root avulsion / 中国病理生理杂志

AIM: To investigate the influence of EGb761 on NOS expression and survival of motoneurons after spinal root avulsion.METHODS: Eighty adult SD female rats were randomly divided into control and EGb761 groups. The C5-T1 nerve roots of right brachial plexus were avulsed and injection of 1 mL of either EGb761 25 mg?kg -1 ?d -1 or normal saline (ip) was performed everyday. The treated rats were killed 1 week, 2 weeks, 4 weeks and 6 weeks following avulsion. The cryostat sections of C7 segment of every rat were collected and carried with NADPH-d histochemistry plus neutral red counterstain. The difference of the numbers of both NOS-positive and survival motoneurons were quantitatively studied. RESULTS: Following avulsion, NOS was expressed in avulsed motoneurons at 1 week, reached to its maximum at 2 weeks and then decreased gradually from 4 weeks to 6 weeks. Motoneurons died from 4 weeks to 6 weeks. With EGb761 treatment, the number of NOS-positive motoneurons were decreased at each time point and the number of survival motoneurons was increased at each time point compared to control rats.CONCLUSIONS: EGb761 protected the spinal cord motoneurons from avulsion injury. This effect may be related to inhibition of NOS expression.

Mitochondrial DNA deletion of the brain tissue of aged rats with learning and memory deficit / 中国病理生理杂志

AIM and METHODS: The ratio of mitochondrial DNA (mtDNA) deletion was measured to find the relationship between mtDNA deletion and aged learning and memory deficit. The aged rats were divided into two groups, aged learning and memory deficit group and aged learning and memory normal group. The ratio of mtDNA deletion was measured by dilution polymerase chain reaction. RESULTS: There are deleted mtDNA (about 4834 bp) in the cerebral cortex, hippocampus and cerebellum of both young and aged rats. The ratios of deleted mtDNA were similar in the cerebral cortex,hippocampus and cerebellum of young rats (about 0.00018%). The ratio mtDNA of aged learning and memory normal rats had increased by five-fold in the cerebral cortex and hippocampus, or one-fold in the cerebellum over young rats. The ratio of aged learning and memory dificit rats had increased by one-fold in the cerebral cortex or 0.8-fold in the hippocampus or two-fold in the cerebellum over aged learning and memory normal rats.CONCLUSIONS: There was really the increase of mtDNA in aging rat brain. And this increase was double in amount in aged learning and memory deficit rats compared to the normal learning and memory aged rats. It is suggested that the mtDNA deletions in the brain regions associated with learning and memory may be contributed to the cellular and molecular mechanism of learning and memory deicit with aged rats.

Effect of antioxidants on secondary conformational transition of aged amyloid ?-peptide_( 1-40) by FT-IR quantitative study / 中国病理生理杂志

AIM: To investigate the mechanism that antioxidants TA9901, inhibit the formation of amyloid-?-protein(A?) fibril. METHODS: Fourier-transform infrared spectroscopy was used to study the secondary structure changes on aging A? in vitro. RESULTS: A? aged alone for 30 min, the content of ?-pleated sheet and ?-turn were 43.17% and 32.9% respectively. A? aged alone for 7 days, the content of ?-pleated sheet increased abuot 10% and produced a shift of random coil toward ?-pleated sheet. TA9901 induced a significant decrease of the content of ?-turn (23.5%) and ?-pleated sheet (26.4%). VE mainly decreased the ?-pleated sheet content (30.8%). The combination of TA9901 and VE promoted transition of ?-turn (16.7%) toward ?-helix and random coil. CONCLUSIONS: Both of TA9901 and VE can effectively diminish the ?-structural content. TA9901 showed more intensitive inhibition than VE. The effect of TA9901 on the secondary structure of aged A? was associated with the mechanism that TA9901 inhibited A? aggregation and fibril formation.

A reactive pattern of ischemia-induced nestin protein in the rat brain / 中国病理生理杂志

AIM: To explore the expressive profile of nestin protein in the focal ischemic brain and to study the recovery mechanism of brain focal infarct . METHODS: Cellular morphology, time-course and distribution pattern of nestin positive response were immunohistochemically examined in different brain regions of 36 adult male SD rats. RESULTS: Nestin positive response of different brain regions in sham operated rats was present in small- and micro-vasculartures and the third ventricle bottom and ependyma. A large number of nestin positive cells were detected in ischemic brain, and were more remarkable in the cortical areas of parietal lobe and preoptic area as well as ischemic caudoputamen. Stellate nestin positive cells were located in the deep layer of ischemic cortex, but fibrillary cells were located in the shallow layer. Nestin positive cells in the ischemic caudoputamen showed the same changes of morphology as those cells in the deep layer of ischemic cortex. Morphological and number alterations of nestin positive cells were the most remarkable at 1 weeks post-ischemia, which showed more hypertrophy and proliferation in morphology, and a marked increase in number was present in the ischemic cerebral cortex and the ischemic caudoputamen. These alterations of nestin positive cells persisted up to 6 weeks post-ischemia, and then, the nestin positive response in the ischemic brain decreased gradually. CONCLUSION: Focal cerebral ischemia induces nestin re-expression on reactive astrocytes, which may be very important to the self-recovery of cerebral infarct.

A?_(5～35) and Apo E4 enhance neuronal intracellular free Ca~(2+) / 中国药理学通报

AIM To study the effects of A? 25～35 and Apo E4 on neuronal intracellular free Ca 2+ ([Ca 2+ ] i). METHODS Hippocampal and cortical neurons suspension of newborn(0～3 days) SD rats was produced. After incubated with fura 2/AM,the neurons suspension was divided into four groups: control, A? 25～35 , Apo E4, A? 25～35 +Apo E4. Each groups [Ca 2+ ] i was measured using a RF 5000 dual wavelength spectrofluorometer after incubated with double distilled water, A? 25～35 , Apo E4, A? 25～35 +Apo E4 for 3 min, respectively. The neurons outocorrelation function(ACF) of the scattering light intersity was analyzed by the microscope quasi elastic light scattering(MQLS) technique The frequency shift line width by ACF. The ? can sympolize the cell menbrane flilidity. RESULTS Both A? 25～35 and Apo E4 could significantly enhance hippocampal and cortical neurons rest [Ca 2+ ] i, furthermore, the effect of 5 ?mol?L -1 A? 25～35 was higher than the effect of 1 ?mol?L -1 A? 25～35 ( P

An experimental exploration of focal inflammatory response in cerebral ischemic foci in the rat / 中国病理生理杂志

AIM: To study the pathological relationship of vascular cell adhesion molecule-1 (VCAM-1) expression and monocyte/macrophage infiltration with focal brain ischemia. METHODS: Immunohistochemical technique and focal brain ischemia/reperfusion model were used in the study in order to explore profiles and time-course of VCAM-1 expression and monocyte macrophage (ED2 positive cell) infiltration in ischemic rat brain. RESULTS: VCAM-1 was up-regulated in microvascular endothelial cells in ischemic cortex at 1h postischemia, and continuously expressed during the time of reperfusion. ED2 positive cells infiltrated into ischemic cortex at 1h iscehmia/ 2h reperfusion and then ED2 positive cells increased gradually with the time of reperfusion, ED2 positive cell infiltration showed apparently relationship with VCAM-1 expression, and both of them exhibited the some changes of time-dependence. CONCLUSION: Cerebral ischemia induced VCAM-1 expression and ED2 positive cell infiltration and VCAM-1 may regulate the recruitment of ED2 positive cells in the ischemic brain region. The results suggested that VCAM-1 and ED2 positive cells may be participated in the pathogenesis of cerebral ischemic injury.

Persistent response of microglia/macrophages following chronic focal cerebral ischemia in rats / 中国病理生理杂志

AIM: To study the microglial/macrophagic reactions to chronic foral cerebral ischmeia METHODS:ED1 and OX42 positive cellular reactive profiles including time-course and distribution as well as morphological changes were explored in the ischemic cortex and the ischemic caudoputamen of 36 SD adult rats by using focal cerebral ischemic model and immunohistochemical method RESULTS: On the 3rd day after ischemia, an increased number of round ED1 positive cells were found in the outer boundary of cortical ischemic foci and the ischemic caudoputamen, and some of the positive cells were present in the cortical ischemic core At 2nd week after ischemia, ED1 positive cells peaked in number, and they were located at cortical ischemic core and lateral caudoputamen, at which they persisted up to 6 weeks after ischemia. On the 3rd day after ischemia, ramified OX42 positive cells became hypertrophy and a marked increase in number, and they were present at the periphery of ischemic foci and in the ischemic caudoputamen At 2nd week after ischemia, OX42 positive cells became more hypertrophy, and a number of round OX42 positive cells were detected in the cortical ischemic core, in which they persisted up to 6 weeks after ischemia. CONCLUSION:Focal cerebral ischemia induces microglial/macrophagic reaction persistently, which may be correlative with neuronal delayed injury and self recovery of ischemic foci.

Inhibitory effect of TA9902 on amyloid ?-peptide 1-42 aggregation by Fourier-transform infrared spectroscopy study / 中国病理生理杂志

AIM: To investigate the mechanism by which TA9902 inhibits the formation of amyloid ?-peptide (A?) fibrils. METHODS: Fourier-transform infrared spectroscopy was used to study the secondary structure changes on aging A? in vitro. RESULTS: The content of ?-pleated sheet were 46.53% in the condition of A? aged alone for 30 min. When A? aged alone for 72 h, the content of ?-pleated sheet increased about 19.4% and produced a shift of random coil toward ?-pleated sheet. TA9902 induced a significant decrease in the content of ?-pleated sheet (36.09%). CONCLUSION: TA9902 effectively diminishes the ?-pleated structural content. The effect of TA9902 on the secondary structure of aged A? is associated with inhibition of A? aggregation and fibril formation.

Specific humoral immune responses in adult rhesus monkeys vac cinated with A?_(1-15) peptide vaccine / 中国病理生理杂志

AIM: To observe the humoral immune response in adult rhesus monkey induced by A? 1-15 vaccine. METHODS: 5 adult male rhesus monkeys were injected intramuscularly with A? 1-15 vac cine at baseline and at week 2, 6, 10, 14, 18, 22. The titer and IgG isotypes of the antibody against A? 1-42 in the serum were measured with ELISA. The specificity of the antibody against A? 1-42 was determined by Wester n blotting. The A? plaques in Tg2576 transgenic mouse brain were stained with t he antisera using immunohistochemistry method. RESULTS: At the eighth week after the vaccination, antibody against A? 1-42 bega n to develop significantly i n the serum. The titers of the antibody increased following vaccine boosted and reached 1: 3 840 at the twenty-fourth week, then decreased after the terminat ion o f inocunation. The IgG1 was accounted for the highest level in the antisera pool . The antibody against A? 1-42 showed high specificity. The A? plaques in Tg2576 transgenic mouse brain were labeled with the antisera. CONCLUSION: A? 1-15 vacci ne could induce vigorously specific humoral immune responses in adult rhesus mon key.

Expression of nerve growth inhibiting factor Nogo-A in ischemic infarct brain in rats / 中国病理生理杂志

AIM: To investigate the dynamic changes of Nogo-A expression in ischemic infarct brain in rats. METHODS: The model of middle cerebral artery occlusion (MCAO) in 80 rats was established and expression of Nogo-A mRNA was measured by immunohistochemistry and hybridization. RESULTS: In the brain of MCAO rats, Nogo-A mRNA expression was decreased at the third day and increased significantly at the 7th day, and reached high level at the 21th day, then remained the high level to the 28th day. Nogo-A protein expression showed the same results. CONCLUSION: Expression of Nogo-A did not change in the early stage of MCAO, but increased significantly in the late stage of MCAO, suggesting that Nogo-A expression may play an important role in the nerve regeneration of brain ischemic injury. [

Pathologic changes of spinal motoneurons function and morphology after root avulsion / 中国病理生理杂志

AIM: To investigate the pathological changes of motoneuron's function and morphology after root avulsion in order to study the neurobiology mechanism of motoneuron death. METHODS: Twenty female adult Sprague-Dawley rats, 200-300 g were used. The C 5-C 8, T 1 roots of the right brachial plexus were avulsed. All rats were killed 3 d, 5 d or 1 week after avulsion. One group of the C 5-C 8 spinal cords freeze sections (40 ?m thick) were collected for the NADPH-d histochemistry with neural red counterstained. Another group of the C 5-C 8 spinal cords freeze sections (40 ?m thick) were collected for the c-Jun immunocytochemistry stain. The paraffin sections (5 ?m thick) were collected for HE stain. The amount of NOS-positive and survival motoneurons was counted. The percentage of NOS expression and motoneuron survive were quantitatively analyzed considering the amount of contra lateral motoneurons as one hundred percent. RESULTS: The NOS expression rate was 0.74%?0.59% (3 d), 24.84%?6.73%(5 d), or 51.16%?8.67% (1 week), respectively. The survive rate was 93.00%?4.32% (3 d), 93.67%?5.27% (5 d), or 89.83%?2.65% (1 week), respectively. The motoneuron expressed c-Jun as early as 3 days after avulsion. The expression declined afterward until one week after avulsion. There was no significant change on the size of motoneuron. The nuclear membrane was still clear but some nuclei were not located in the middle of the cell body. There were some nucleoli with the chromatin condensation. CONCLUSION: The motoneuron NOS expression and cell death were increased within one week after spinal root avulsion. meanwhile, the c-jun expression was decreased. The NO/NOS may induce the motoneuron death by inhibiting the regenerating reactions of motoneuron after root avulsion injury.