The Korean Journal of Physiology and Pharmacology
- Volume 1 Issue 3
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- Pages.303-313
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- 1997
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- 1226-4512(pISSN)
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- 2093-3827(eISSN)
Regulatory Role of Cyclic Nucleotides in Non-Adrenergic Non-Cholinergic Relaxation of Lower Esophageal Sphincter from Dogs
개 하부식도괄약근의 비아드레날린성, 비콜린성 이완반응에 있어서 Cyclic Nucleotide의 역할
- Kim Young-Tae (Department of Pharmacology, College of Medicine, Pusan National University) ;
- Rhim Byung-Yong (Department of Pharmacology, College of Medicine, Pusan National University)
- Published : 1997.06.01
Abstract
The role of the lower esophageal sphincter(LES) is characterized by the ability to maintain tone and to relax allowing the passage of a bolus. It is known that LES relaxation during swallowing may be induced by the cessation of the tonic neural excitation and the activation of non-adrenergic, non-cholinergic(NANC) inhibitory neurons. Furthermore, it is generally accepted that the relaxation of the smooth muscle is mediated primarily by the elaboration of adenosine 3',5'-cyclic monophosphate(cyclic AMP) and guanosine 3',5'-cyclic mono-phosphate(cyclic GMP) via activation of adenylate cyclase and guanylate cyclase, respectively. It is thus possible that cyclic nucleotides might be a second messenger involved in neural stimulation-induced relaxation of LES, although a relationship between relaxation and changes in cyclic nucleotides after neural stimulation has not been established. The present study was performed to define the participation of cyclic nucleotides in the relaxation of LES of dog in response to neural stimulation. Electrical field stimulation(EFS) caused relaxation of the canine isolated LES strips in a frequency-dependent manner, which was eliminated by pretreatment with tetrodotoxin
Keywords
- Lower esophageal sphincter;
- Cyclic AMP;
- Cyclic GMP;
- Non-adrenergic non-cholinergic relaxation;
- Nitric oxide