CALCIUM ANTAGONISTIC EFFECT OF dl-TETRAHYDROPALMATINE ON ISOLATED RAT UTERUS / 西安交通大学学报(医学版)

ABSTRACT

The calcium antagonistic effect of dl-tetrahydropalmatine(THP) on isolated rat uterus was observed. THP decreased significantly uterine contraction induced by oxytocin, KCl, CaCl_2. THP nonparallelly shifted cacium chloride dose-response curve to the right, and decreased the maximal response, showing noncompetitive antagonism, PD'_2 value was 4.6. THP obviously decreased the intracellular and extracellular calcium-dependent components in oxytocin-induced contraction response. These results have shown that THP not only mainly inhibited potential dependent calcium channel, but also decreased calcium relesese from intracellular stores.