负鼠食管平滑肌环形层对电场刺激反应潜伏期的一些决定因素。

Some determinants of latency of off-response to electrical field stimulation in circular layer of smooth muscle of opossum esophagus.

作者信息

Christensen J, Arthur C, Conklin J L

出版信息

Gastroenterology. 1979 Oct;77(4 Pt 1):677-81.

Abstract

Transverse strips from smooth muscle of opossum esophagus were subjected to electrical field stimulation of intramural nerves to study the latency of the off-response. Latency is the time from the end of the stimulus train to the beginning of the off-response. Latency increased from one end of the smooth muscle segment to the other; it was shortest proximally and longest distally. Variables altering this latency gradient were sought. Strip width and tension had no effect (P greater than 0.02). Longer stimulation trains shortened latency (P less than 0.02). Krebs solution was modified by changing potassium concentration and by the addition of: hexamethonium, 1 x 10(-4) M; D-tubocurarine, 1 x 10(-4) M; bethanechol, 5 x 10(-7) M; carbachol, 5 x 10(-7 M; physostigmine, 1 x 10(-7) M; propranolol, 1 x 10(-6) M; tolazoline, 5 x 10(6) M; norepinephrine, 1 x 10(-5) M; isoproterenol, 1 x 10(-6) M; and dopamine, 1 x 10(4) M. Increased potassium concentrations shortened latency, and decreased potassium concentrations lengthened it (P less than 0.02). Carbachol, bethanechol, physostigmine, and isoproterenol shortened latency (P less than 0.02). Hexamethonium, D-tubocurarine, tolazoline, propranolol, norepinephrine, and dopamine had no effect (P greater than 0.02).

摘要

对负鼠食管平滑肌的横向条带施加壁内神经的电场刺激，以研究脱逸反应的潜伏期。潜伏期是指从刺激序列结束到脱逸反应开始的时间。潜伏期从平滑肌段的一端到另一端逐渐增加；近端最短，远端最长。研究人员寻找改变这种潜伏期梯度的变量。条带宽度和张力没有影响（P大于0.02）。较长的刺激序列缩短了潜伏期（P小于0.02）。通过改变钾离子浓度并添加以下物质对 Krebs 溶液进行了改良：六甲铵，1×10⁻⁴ M；D -筒箭毒碱，1×10⁻⁴ M；氨甲酰甲胆碱，5×10⁻⁷ M；卡巴胆碱，5×10⁻⁷ M；毒扁豆碱，1×10⁻⁷ M；普萘洛尔，1×10⁻⁶ M；妥拉唑啉，5×10⁻⁶ M；去甲肾上腺素，1×10⁻⁵ M；异丙肾上腺素，1×10⁻⁶ M；以及多巴胺，1×10⁻⁴ M。钾离子浓度升高缩短了潜伏期，钾离子浓度降低则延长了潜伏期（P小于0.02）。卡巴胆碱、氨甲酰甲胆碱、毒扁豆碱和异丙肾上腺素缩短了潜伏期（P小于0.02）。六甲铵、D -筒箭毒碱、妥拉唑啉、普萘洛尔、去甲肾上腺素和多巴胺没有影响（P大于0.02）。