[The effect of TWP on the reactivity of AChR on the end-plate membrane of frog sartorius].
OBJECTIVE
To study the effect of Tripterygium Wilfordii Polyglycosidium (TWP) on the reactivity of n-Acetylcholine receptor (nAChR) on the end plate membrane.


METHODS
Using the microionophoretic method, we applied the exogenous acetylcholine chloride (AChCl) to the superficial end-plates of the isolated nonuniform stretched frog sartorius, and acetylcholine potential (AChP) recorded was taken as an indicator of the reactivity of the nAChR in the end plate.


RESULTS
1. After the addition of TWP, the apparent change of AChP was recorded at 20 min in the 20 mg/L group, and at 10 min in the 40 mg/L and 60 mg/L groups respectively. 2. Within the 20 mg/L and 40 mg/L TWP groups, the change in amplitude of AChP showed significant difference with the time (P < 0.05), the greatest being at 60 min. 3. In the 60 mg/L TWP group, action potential was recorded at 40 min, 60 min and 80 min. 4. There was significant difference in the percentage of AChP amplitude change between the three concentration groups (P < 0.05), and the highest percentage of change appeared in the 60 mg/L group.


CONCLUSIONS
TWP can increase the reactivity of nAChR in the end plate membrane, and there exist an apparent concentration-effect relationship and a certain time-effect relationship.
Li
Keyong
K
Department of Physiology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, China.
Lü
Guangneng
G
Zhang
Yun
Y
Wang
Tao
T
Xu
Jianguo
J
D000818:Animals; D002023:Bufo bufo; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000494:pharmacology; D005260:Female; D006027:Glycosides / Q000494:pharmacology*; D008297:Male; D009045:Motor Endplate / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology; D009469:Neuromuscular Junction / Q000502:physiology; D011950:Receptors, Cholinergic / Q000187:drug effects*; D029757:Tripterygium / Q000737:chemistry*
D004365:Drugs, Chinese Herbal; D006027:Glycosides; D011950:Receptors, Cholinergic