The Comparative Study Of Pharmacodynamics Of Five Alcoholic Extractives From Chinese Herbs On Anticonvulsant Action

Objective To compare the pharmacodynamics of five alcoholic extractives(Scorpion,SP,Centipede,CP,Stiff Silkorm,SS,Lumbricus,LB,Cicada Slough,CS)on anticonvulsion,and explore their mechanism of anticonvulsant action. Methodsâ… Maximal electroshock seizure(MES) was adopted to analyse the relative of dose and effect, relative of time and effect, including maximal efficacy and potency of these five extractives in mice given by ig administration.â…¡Metrazol seizure test(MET) was used to compare seizure latency, anticonvulsant rate and mortality of mice with every extractives.â…¢Pharmacodynamic parameters of five alcoholic extractives were assayed by means of Pharmacological Effective Method.â…£Using the model of seizure rats induced by penicillin localized injected in cortex,we studied the effect of extractives on seizure latency, frequency of epileptiform discharge, highest wave of hippocampus EEG(Recoded by RM6240C multichannel physiological signal collection and analysis recorde), the changes of convulsant behaviors and the latency of seizure.â…¤The neurotransmitters content related to epilepsy in brain were determined by high performance liquid chromatography(HPLC) in order to compare the effect of extractives on Glu, Asp, Gly and GABA of hippocampus. Results and conclusionsâ… all the five extractions could dose-dependently antagonize MES in mice. Maximum efficacy of extractions ranged from maximum to minimum were SP, SS, LB, CS, CP, and the sequence of potency were SP, CS, SS, CP, LB.â…¡Except for CP, all the other four extractions could prolong latent period on MET in mice, and the sequence from maximum to minimum were SS, SP, CS, LB, CP, at the same time, The effect of SS was better than that of LTG.â…¢The effect of these extractions produced after 30min ig, and peaked after about 1h on average, however, persistent time of them was different. Persistent time of CP was 2h, but that of SP lasted for about 7h. It could be conjectured that all of the five alcoholic extractives belong to short-half period preparations studied by Pharmacological Effect Method.â…£SP was the most effective extraction to antagonize the penicillin-induced seizure. Anticonvulsant properties of SP resembled LTG, SS, CS, LB also had effect in penicillin-kindling model, but CP hadn't.â…¤The anticonvulsant mechanism of SP and LB was probably due to increasing the level of GABA, however, CS was related to decreasing Glu level. The anticonvulsant mechanism of SS might have relationship with the two mentioned aspects. While CP had no obvious effect on neurotransmitters content related to...