豚鼠结肠带皮单个平滑肌细胞中肌醇1,4,5-三磷酸诱导的收缩

Inositol 1,4,5-trisphosphate-induced contraction in skinned single smooth muscle cells from guinea-pig taenia coli.

作者信息

Ohata H, Maeda T, Momose K

机构信息

Department of Pharmacology, School of Pharmaceutical Sciences, Showa University, Tokyo, Japan.

出版信息

J Pharmacobiodyn. 1988 Jul;11(7):479-82. doi: 10.1248/bpb1978.11.479.

DOI:10.1248/bpb1978.11.479

PMID:3263492

Abstract

Inositol 1,4,5-trisphosphate (IP3) caused a contraction in skinned single smooth muscle cells from the guinea-pig taenia coli. The contractile response to IP3 was rapid (half time less than 5 s), concentration-dependent (0.01-10 microM, EC50; 0.1 microM) and also depended on the concentration of Ca2+ during preloading. IP3 induced a rapid 45Ca2+ release from the skinned single cells which were preloaded with 10(-6) M Ca2+. The contractile response caused by IP3 was not enhanced by simultaneous application of caffeine (25 mM). The inhibitory effect of procaine on IP3-induced contraction was less than that on caffeine-induced contraction. These results suggest that IP3 also plays an important role in the contractile response in smooth muscle cells from guinea-pig taenia coli and that the mechanism of Ca2+ release from intracellular storage sites by IP3 is different from that by caffeine.

摘要

肌醇1,4,5 -三磷酸（IP3）可引起豚鼠结肠带皮单个平滑肌细胞收缩。对IP3的收缩反应迅速（半衰期小于5秒），呈浓度依赖性（0.01 - 10微摩尔，半数有效浓度；0.1微摩尔），且还取决于预负荷期间的Ca2+浓度。IP3可诱导预先用10(-6) M Ca2+预负荷的带皮单个细胞快速释放45Ca2+。同时应用咖啡因（25毫摩尔）不会增强IP3引起的收缩反应。普鲁卡因对IP3诱导收缩的抑制作用小于对咖啡因诱导收缩的抑制作用。这些结果表明，IP3在豚鼠结肠带平滑肌细胞的收缩反应中也起重要作用，且IP3从细胞内储存位点释放Ca2+的机制与咖啡因不同。