GTPγs对柴胡皂甙(I)刺激胰腺腺泡酶分泌的影响

为了解柴胡皂甙(I)SA(I)]刺激大鼠胰腺腺泡酶分泌的信号传导通路,研究了GTPγs对SA(I)剌激通透腺泡细胞酶分泌的影响.用SLO通透细胞的同时,加入GTPγs在15min期间能诱发酶分泌,10'mol·L-1GTPγs有最大促泌效应.GTPγs浓度依赖性的增强SA(I)促酶分泌作用,l0-7 mol·L-1 GTPγs导致10-5mol·L-1 SA(I)刺激酶分泌量增加到1.6倍.用SLO预通透腺泡10min后,加入GTPγs使SA(I)刺激酶分泌的量-效曲线左移,SA(I)的EC50从2 0×10-5mol·L-1减小到1 0×10-5mol·L-1.以上结果提示,SA(I)活化受体偶联的G蛋白包括在其刺激酶分泌的信号传导通路中.

GTPγs MODULATION OF SAIKOSAPONIN(I) STIMULATED AMYLASE SECRETION IN ISOLATED PANCREATIC ACINI

To elucidate the site of action of Saikosaponin (I) in pancreatic acinar cells, the modulatory effects of guanosine 5'-triphosphate(GTPγs) were investigated in SLO permeabilized pancreatic acinar cells. In a permeabilizing medium, GTPγs addition induced 15min amylase secretion, the effects being maximal at 10-7mol·L-1. GTPγs effects were concentration dependent. GTPγs 10-7mol·L-1 increased amylase secretion stimulated by 10-5mol·L-1 SA(I) 1.6 fold. After acinar cells were pre-permeabilized with SLO for 10min, GTPγs shifted the dose-response curve of SA(I) stimulated amylase secretion to the left, decreasing EC50 from 2.0×10-5 to 1.0×10-5mol·L-1. These results suggest receptor-coupled G protein activation is involved during SA(I) stimulation of amylase secretion.