The impairment of learning and memory function in the central nervous system(CNS)is one of the main features of aging and Alzheimer' s disease (AD). Many experimental results have showed that long- term memory(LTM) is related to long- term potentiation(LTP) and long- term depression (LTD). They intluenee each other. The relationship between LTP and LTD is complex. Therefore, it is important to study the learning and memory mechanism from LTP、LTD and gene expression in the CNS.

The impairment of learning and memory function in the central nervous system(CNS)is one of the main features of aging and Alzheimer's disease(AD).Many experimental results have showed that long- term memory( LTM) is related to long- term potentiation( LTP) and long- term depression(LTD).They influence each other.The relationship between LTP and LTD is complex.Therefore,it is important to study the learning and memory mechanism from LTP、LTD and gene expression in the CNS.

OBJECTIVE:To compare the contents of trace elements in different parts of Piper kadsura.METHODS: Trace elements in leaf, micro-stem and macro-stem of P. kadsura were determined with inductive coupled plasma emission spectrometer. The contents of trace elements in the different parts were analyzed and compared. RESULTS: The content of Mg in the leaf was the highest among all trace elements, followed by Fe,Mn,Zn,Ti,Sr,Ba,Pb,B,Cu,Ni,Cr,Cd.The content of V in the macro-stem was higher than in the other parts. The contents of trace elements in micro-stem were all lower than in the other parts except of Sn. CONCLUSION: The leaf and stem of P. kadsura maybe has some complementary pharmacological function.

The purpose of the present work is to observe cGMP positive cells after cerebral ischemia-reperfusion in the gerbil hip-pocampus. Immunofluorescent methods were used in gerbil hippocampal tissue slices. The results showed that after cerebral is-chemia cGMP synthesis in the CAi-a subfields was increased, cGMP positive cells were distributed mainly in CA1 subfield. Mostof cGMP positive cells were astrocytes. The number of small round cGMP positive cells were increased after recirculation follow-ing ischemia in the dentate gyrus. These results indicate that after cerebral ischemia cGMP synthesis was increased in the CA1-asubfield, It is possible that astrocytes play an important role in the regulation of metabolism in the early stage after ischemia-reperfusion.

Objective To Explore the effect of Cassia Seed budding transforming organic vanadium. Methods Separate organic vanadium from inorganic vanadium in Cassia Seed sprouts by dislysis bag. The content of total vanadium and inorganic vanadium were determined by using the method of Graphite Atomic Absorption Spectrophotometry. The transformation efficiency of organic vanadium in the Cassia Seed spouts was calculated. Results The seed coat of Cassia Seed could accumulate massive inorganic vanadium existing in environment during the process of its natural growing period,but the transformation efficiency of organic vanadium mainly occurred inside seed coat of Cassia Seed. Condusion Cassia Seed budding is one pathway of the biologic organification of vanadium.

Objective To explore the determination of elements selenium content in Se Semen Cassiae. Method Selenium content in Se Semen Cassiae was measured by graphite atomic absorption spectrophotometer. Result and Conclusion An appropriate extraction method and digesting condition were screened out. The determined results were accurate when the digested sample was dissolved and metered volume with 1% HNO3 which containing 0.1% Tween 80.

AIM To observe the effects of L NNA on glial fibrillary acidic protein (GFAP) production in the gerbil hippocampus after recirculation following ischemia. METHODS Both vessels occlusion and immunofluorescent methods in gerbil hippocampal tissue slices incubated in vitro were used. RESULTS Recirculation following ischemia led to a rise on GFAP concentration in the hippocampus. GFAP positive cells mainly distributed in rediatum layer and molecullar layer in the hippocampus, L NNA decreased GFAP synthesis. CONCLUSION L NNA is a strong inhibitor of nitric oxide synthase(NOS). It is possible that the role of endogenous NO mediated GFAP synthesis is inhibited by L NNA.

AIM: To study regional cerebral blood flow (rCBF) and neuronal apoptosis in penumbra following focal cerebral infarction in rats.METHODS: To establish the model of focal cerebral infarction based on the principle of photochemical initiation of thrombosis.Laser Doppler flowmetry was used to measure rCBF in ischemic core and penumbra.The numbers and anatomic distribution of apoptosis cells were examined in situ histologically with terminal deoxynucleotidyl transferase(TdT)-mediated dUTP-fluorescein nick end-labeling(TUNEL) assay in adjacent sections.RESULTS: rCBF in penumbra decreased to the minimum at(6 h) in which it was 30.88%?7.11% of normal.From 9 h to 48 h,rCBF in penumbra increased gradually.At 48 h,91.90%?4.56% of normal cerebral blood flow was recovered which was significant differences than others.Terminal deoxynucleotidyl transferase(TdT)-mediated dUTP-fluorescein nick end-labeling(TUNEL) assay demonstrated that TUNEL-positive cells occurred at 6 h and were expending in a radial fashion only in penumbra.The numbers of apoptosis cells were progressively increased with time and to the maximum in penumbra after 48 h following focal cerebral infarction.CONCLUSION: There were delayed neuronal apoptosis following focal cerebral infarction.The mechanism may be related to ischemia-reperfusion injury induced by the recovery of rCBF in penumbra.

AIM: To investigate the changes of somatosensory evoked potential(SEP), nitric oxide (NO) levels both in serum and in brain tissue after subarachnoid hemorrhage(SAH) and the influence of Ginkgo biloba extract(GBE) on them. METHODS: Wistar rats were divided into sham-operated group, pure SAH group and GBE-treated group. Dynamic changes of regional cerebral blood flow( rCBF),SEP, and NO levels both in serum and in brain tissue were detected within 24 hours after operation. RESULTS: In pure SAH group, rCBF decreased immediately after operation, with no tendency to recover within 24 hours. Latency of SEP delayed progressively from 1 hour to 24 hours after SAH.NO levels in serum and in brain tissue decreased and increased respectively from 1 hour to 24 hours after SAH. GBE effectively antagonized the changes of above parameters. CONCLUSION: SEP is useful in the judgement of cerebral ischemic damage after SAH. Decrease of serum NO and increase of brain NO are important factors leading to cerebral vasospasm and neural damage respectively after SAH. GBE relieves cerebral ischemic damage by reversing the pathological alterations of NO.