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Objective To observe dexmedetomidine coordinate with mlelatonin attenuate the scopolamine-induced delirium in rats and its mechanism.Methods Thirty male adult SD rats aged 6-8 weeks were randomly divided into six groups:normal saline control group (group C),scopolamine-induced delirious model group (group S),dexmedetomidine group (group D),mlelaton group (group M),α-bungarotoxin antagonism group (group BM),joint protection group (group DM).A model of delirium was reproduced by intraperitoneal inj ection of scopolamine 1.8 mg/kg.The rats in group C was given equal sterile normal saline instead,the rats in group D was intraperitoneal injected of dexmedetomidine 40 μg/kg 15 minutes before scopolamine injection,the rats in group M was intrap-eritoneal injected of mlelaton 5 mg/kg in the contralateral abdominal at the same time with scopolamine injection,the rats in group BM was intraperitoneal injected ofα-BGT 1 μg/kg 15 minutes before scopolamine injection and mlelaton 5 mg/kg in the contralateral abdominal at the same time with scopolamine injection,the rats in group DM was intraperitoneal injected of dexmedetomidine 40 μg/kg 15 minutes before scopolamine injection and mlelaton 5 mg/kg in the contralateral abdominal at the same time with scopolamine injection.The rats were assigned for open field test 15 minutes before and 10 minutes after model reproduction for 15 minutes.The level ofα7nAchR in serum was deter-mined by enzyme linked immunosorbent assay.Results When compared with group C,rats in group S ran significant longer total distance and space distance,had faster total speed and space speed (P<0.05).When compared with group S,rats in group D,group M,group DM ran significant shorter total distance and space distance,had significant slower total speed and space speed (P<0.01 );when compared with group D,rats in group DM ran significant shorter total distance and space dis- tance (P<0.05 ),had slower total speed and space speed,however without significant statistical difference.When compared with that in group C,the level of α7nAChR in serum were significantly decreased in group S (P<0.05).When compared with group S,the level of α7nAChR were signifi-cantly increased in group D (P<0.01).There were no significant difference between group M and group S (P=0.96).When compared with group D,the level of α7nAChR had an elevated trend in group DM.Conclusion Dexmedetomidine can improve the symptoms of delirium,possibly by in-creasing the activity of alpha 7nAChR.Melatonin may improve the effect of dextromidine on delirium.
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Objective To investigate the relationship between the nerve growth factor ( NGF ) induced hippocampal neuroregeneration and homeobox gene Lhx 8.Methods Seventy-two SD rats were divided into control group , transected group, NGF group, transected combined with NGF group after right fimbria-fornix transection and NGF intracerebroventricular injection . Real-time PCR and Western blotting were applied to detect the gene and protein expression of Lhx8 in each group.The choline acetyltransferase ( ChAT)/Lhx8 double labeled cells in subgranular zone ( SGZ) of hippocampus in each group were detected by immunofluorescence .Results The expression of Lhx8 gene and protein in the transected , NGF group and especially in the transected combined with NGF group was obviously higher than in the control group .The number of ChAT/Lhx8 double labeled cells in the NGF group and the transected combined with NGF group was obviously more than in the control group and transected group . Conclusion The hippocampal neuroregeneration which induced by NGF intracerebroventricular injection was associated with the higher expression of Lhx8.
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Aim Through identification of the difunc-tionality of neuroprotection and passage of blood-brain barrier ( BBB) for RDP-BDNF fusion protein to offer a new strategy to treat brain diseases. Methods BDNF was conjugated to a novel cell penetrating peptide known as RDP which was derived from rabies virus gly-coprotein ( RVG) . The fusion protein RDP-BDNF was expressed in E. coli BL21 ( DE3 ) . After the intrave-nous injection of RDP-BDNF, the time effect curve of RDP-BDNF in the brains and serum was examined. Additionally , Morris water maze test was used to evalu-ate the effect of RDP-BDNF on scopolamine-induced amnesic mice, and the mechanism was also studied. Results RDP-BDNF could cross the BBB and exhibi-ted neuroprotective effects on the treatment of cognitive deficit induced by scopolamine in dementia model mice. Conclusions Delivery of protein therapeutics using RDP might offer a new and exciting strategy to treat brain diseases.
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Objective To observe the basic rhythm of myoelectrie activities of sphcter of Oddi (SO)and explore its biological significance.Methods Healthy adult rabbits(n=32)were randomized into 4 groups with 8 in each.The first group was for recording of myoelectric activities of SO after keeping fast for 18 hours.The second group was manipulated to observe the myoelectric activities of SO after food infusion through the stoma in stomach.The myoelectric activities of SO in the third group were monitored after the classical Nardi test was performed on these rabbits.The fourth group was used to observe the myoelectric activities of SO after the cholinergic receptors had been blocked.Using the double claw metal electrodes which were put into SO and duodenum through the plasma membrance,the myoelectric signal were recorded with RM6240 multi-channel physiologic recording and signal processing system and non-stop recording was conducted for 120-150 mins.Results 1)Spike Potentials of SO with the frequency was observed in rabbits that had been fasting.2)Myoelectronic activity of SO was observed in rabbits infused with 50 ml milk through stoma.3)After the administration of 1 mg morphine and 1 mg neostigmine i.v,the myoelectric activities of SO were noted as long-lasting persistent MASO.4)Administration of anisodamine 1 mg(i.v.)in the empty abdomen group dismissed SPSO and MASO.This state lasted for 120 min before SPSO gradually reconverted to the state of empty abdomen.Conclusion There are four patterns of myoelectric activities of SO,i.e,tensional waves under empty abdomen indicating a state in which the SO kept a basic tension level.Peristaltic waves under intake of food.Spastic waves under the stimulation of drugs and relaxant waves under the post-ganglionic block of cholinergic receptors were observed in the present study.Correspondingly,their mechanic locomotion is inferred as the basic tensional state to faciliate the deposition and condensation of bile,the peristalsis for the entry of bile into duodenum,the spasmus so that the bile can not be released into duodenum under pathological situation or the effect of drugs.the long lasting relaxant state after effective inhibition of post-ganglionic cholinergic receptors,respectively.The above results indicate that there are more than two states that is ON or OFF in SO and the concepts of contract and peristalsis of SO should be distinguished.
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Objective To study effects of cholecystokinin (CCK) on occuring of electrogastric arrhythmias. Methods The contens of cholecystokinin (CCK) nerves, cholinergic (Ach) nerves and nitregic nervous (NOS) nerves in antral myenteric plexus were studied using histochemistry and immunocytochemistry. Results (1) The electrogastric dysrhythmias occurred in the model and CCK groups rats, the abnormal rhythm index and coefficent of variation (cv) of slow wave frequency were singnificantly increased compared with the control ( P
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s Objective To study the changes in cholinergic nerves and nitrergic nerves in colonic myenteric plexus in rats with slow transit constipation. Methods Slow transit constipation model of rat was reproduced by feeding Diphenoxylate. The changes in cholinergic nerves and nitrergic nerves in colonic myenteric plexus were studied by histochemical technology. Results In the rats with slow transit constipation, the numbers of nitriergic cells and cholinergic cells in the myenteric nerves were significantly decreased compared with control group. The volume of neuron in AchE ganglia was larger than that of control. Conclusion Dysfunction of colon transit was related with the changes in cholinergic nerves and nitrergic nerves of colonic myenteric nerve plexus in rats with slow transit constipation.
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Objective To study the neurotoxic effects of acute exposure of methylmercury at low dose and to provide some experimental data for deeply exploring the early mechanism of neurotoxicity of methylmercury. Methods SD rats were administered with methylmercury chloride by intraperitoneal injection with different doses of 0.05, 0.50 and 5.00 mg/kg and different exposure times of 20 min, 1 h, 4 h, 24 h. Mercury, ACh and AChE contents in rat brains were measured. Results Mercury contents in rat brains significantly increased after 20 min-exposure at both 0.50 and 5.00 mg/kg doses. Significant increase occurred after 4 h exposure at dose of 0.05 mg/kg. ACh and AChE in rat brains significantly changed after 20 min at every dose, showing certain dose-response and time-response relations. Conclusion Changes of ACh and AChE in rat brain after administration of low dose(0.05 mg/kg) and short time(20 min) exposure suggested certain modulation of CNS had been initiated. With the increases of exposure dose and time, methylmercury might begin to accumulate in rat brain and induce the significant changes of ACh and AChE.
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Four constitunets were isolated from the flower of Rhododendron molle ( BI. ) G. Don. One of these was named Rdl.The acute LD50 of Rdl in mice ( iv ) was found to be 4742 ug/kg.The hypotensive effect of Rdl was studied in various anesthesized animals. In cats, the dosage of 100, 300 and 500 Hg/kg of the Rdl ( iv ) reduced the blood pressure by 10:9% ( P
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This paper is to report the autonomic innervation of the gall bladder and extrahepatic bile ducts studied on whole mount stretch preparations and cryostat sections with acetylcholinesterase staining, glyoxylic acid induced fluorescence histochemical method, and PAP immunohistochemical method.The autonomic nerves of the gall bladder and extrahepatic bile dudts in cats consist of two plexuses, composed of cholinergic, adrenergic and peptidergic nerves, and situated in the subserosa and submucosa respectively. They are known as subserosal and submucosal ganglionated plexuses. They distribute in the region from the fundus of the bladder, to the neck and the cystic duct, through the common bile duct downward, finally to the duodenal papilla.The adrenergic nerves mainly run along the, blood vessels, distributing in the serosa and lamina propria of the mucosa of the bladder, and participating in the formation of the subepithelial and perivasctilar plexuses. The adrenergic nerves are most densely distributed in the cystic duct and mosl sparsely in the fundus. This finding is in good agreement with the tissue concentration of noradrenaline(NA) determined with biochemical asssay, which is also the highest in the tissue of the cystic duct. The difference of NA concentration between the cystic duct tissue and other biliary tissues was statistically Gignificant(P0.05).Immunohistochemical study revealed that there are 4 kinds of immunoactivc peptidergic nerves, i. e. nerves with vasoactive intestinal polypeptide (VIP), substance P(SP), L-enkephalin (L-ENK), and somatostatin (SOM) respectively. The 4 kinds of nerves distribute extensively in all the tissue layers of the ex-trahepatic biliary tract and participate in the formation of all the nerve plexuses. Among them, VIP nerves are the richest, then the SP and L-ENK nerves, and the SOM nerves the sparsest. In general, peptidergic nerves are densely distributed in the sphincter of Oddi.Finally the physiological significance of the peptidergic nerves was discussed.
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The innervation and distribution of 5-HT cells in gastric wall of rabbit and rat were studied by means of histochemical techniques of monoamine fluorescence and cholinesterase. And the morphological relation between them was investigated using the consecutive method for demonstrating the fluorescence and ChE on the same section. At the fundic gland, 5-HT cells were in contact with both the adrenergic and cholinergic axonal terminals. There are adrenergic and cholinergic terminals to innervate the gland cells of fundic gland, partial fundic gland the dual axonal terminal are identical in their localization and morphological outline. The loyer of muscle and smooth muscles surrounding the arteriole in various stomach layers were innervated by both adrenergic and cholinergic terminals, some of them are superimposed at the samelocalization. There are a lot of nsChE nerve ending network in gastric lamina propria beneath epithelium of gastric mucous membrane, it was discussed about their sensory nature in this paper.