Relaxant Effect of Spermidine on Acethylcholine and High K+-induced Gastric Contractions of Guinea-Pig.
10.4196/kjpp.2008.12.2.59
- Author:
Young Chul KIM
1
;
Jae Hoon SIM
;
Woong CHOI
;
Chan Hyung KIM
;
Ra Young YOU
;
Wen Xie XU
;
Sang Jin LEE
Author Information
1. Department of Physiology, Chungbuk National University College of Medicine, Cheongju 361-763, Korea. physiokyc@chungbuk.ac.kr
- Publication Type:Original Article
- Keywords:
Stomach;
Relaxation;
Calcium current;
Ca2+release;
Spermidine
- MeSH:
Acetylcholine;
Caffeine;
Calcium;
Calcium Channels;
Carbachol;
Contracts;
Muscle, Smooth;
Putrescine;
Relaxation;
Spermidine;
Spermine;
Stomach
- From:The Korean Journal of Physiology and Pharmacology
2008;12(2):59-64
- CountryRepublic of Korea
- Language:English
-
Abstract:
In our previous study, we found that spermine and putrescine inhibited spontaneous and acetylcholine (ACh)-induced contractions of guinea-pig stomach via inhibition of L-type voltage- dependent calcium current (VDCCL). In this study, we also studied the effect of spermidine on mechanical contractions and calcium channel current (IBa), and then compared its effects to those by spermine and putrescine. Spermidine inhibited spontaneous contraction of the gastric smooth muscle in a concentration-dependent manner (IC50=1.1+/-0.11 mM). Relationship between inhibition of contraction and calcium current by spermidine was studied using 50 mM high K+-induced contraction: Spermidine (5 mM) significantly reduced high K+(50 mM)-induced contraction to 37+/-4.7% of the control (p<0.05), and inhibitory effect of spermidine on IBa was also observed at a wide range of test potential in current/voltage (I/V) relationship. Pre- and post-application of spermidine (5 mM) also significantly inhibited carbachol (CCh) and ACh-induced initial and phasic contractions. Finally, caffeine (10 mM)-induced contraction which is activated by Ca2+-induced Ca2+release (CICR),` was also inhibited by pretreatment of spermidine (5 mM). These findings suggest that spermidine inhibits spontaneous and CCh-induced contraction via inhibition of VDCCL and Ca2+releasing mechanism in guinea-pig stomach.
