Localization of adrenergic receptors in bovine esophageal groove

Kang, Tong-mook; Cho, Je-yoel; Park, Jun-hong; Yang, Il-suk

Korean Journal of Veterinary Research 1993;33(4):617-622.

Tong-mook Kang¹, Je-yoel Cho¹, Jun-hong Park², Il-suk Yang¹

¹College of Veterinary Medicine, Seoul National University
²College of Agriculture, Cheju National University

소(牛) 식도구 평활근의 Adrenergic receptor 존재부위에 관한 연구

강동묵¹, 조제열¹, 박전홍², 양일석¹

¹서울대학교 수의과대학
²제주대학교 농과대학 수의학과

Abstract

The preliminary studies on the localization of adrenoceptors were performed on smooth muscle strips of bovine esophageal groove. The mechanical activity of the muscle strip was recorded isometrically in vitro.w In the bottom circular muscle strips. the excitatory ${alpha}-adrenergic$ responses were not blocked by tetrodotoxin$(2.1{ imes}10^{-6}M)$ and denervation which was carried by cold storage of strips for 48 hrs in Tyrode's solution at $5-6{^{circ}C}$ without oxygen supply. These excitatory ${alpha}-adrenergic$ responses were partially blocked by atropine. In the lip longitudinal muscle strips, the inhibitory${eta}-adrenergic$ responses were not blocked by pretreatment of tetrodotoxin and atropine. The results suggest that ${eta}-adrenergic$ receptors mediating relaxations are located on the postsynaptic smooth muscle cells, whereas ${eta}-adrenergic$ receptors mediating contractions are located both in the smooth muscle cells and in the cholinergic neurones.

Key Words: Espohageal groove, adrenoceptor, smooth muscle