Ueda S, Mutoh S, Yano S, Ikegami K, Sakanashi M
Eur Urol. 1982;8(1):37-41. doi: 10.1159/000473475.
Isolated dog urinary bladder showed spontaneous miniature contractions under a steady state. In dome preparations, norepinephrine and isoproterenol decreased the frequency of miniature contractions, while epinephrine produced biphasic responses on it; increase by low concentration and decrease by high concentrations. The height of miniature contractions was decreased by these drugs. In trigone preparations, norepinephrine and epinephrine increased the frequency of miniature contractions, while isoproterenol decreased it. These drugs decreased the height of miniature contractions. In both preparations, phentolamine enhanced the decreases in frequency and height by norepinephrine, epinephrine and isoproterenol, while propranolol depressed or reversed them. A computer analysis showed positive and significant correlations between changes in tension development of bladder and frequency and height of miniature contractions. Results indicate that miniature contractions in both dome and trigone of isolated dog urinary bladder are increased by activation of alpha-adrenoceptors and decreased by activation of beta-adrenoceptors.
离体犬膀胱在稳态下呈现自发性微收缩。在膀胱顶部标本中，去甲肾上腺素和异丙肾上腺素降低了微收缩的频率，而肾上腺素对其产生双相反应；低浓度时增加，高浓度时降低。这些药物降低了微收缩的幅度。在膀胱三角区标本中，去甲肾上腺素和肾上腺素增加了微收缩的频率，而异丙肾上腺素降低了频率。这些药物降低了微收缩的幅度。在两种标本中，酚妥拉明增强了去甲肾上腺素、肾上腺素和异丙肾上腺素对频率和幅度的降低作用，而普萘洛尔则抑制或逆转了这些作用。计算机分析显示，膀胱张力发展的变化与微收缩的频率和幅度之间存在正相关且具有显著性。结果表明，离体犬膀胱顶部和三角区的微收缩通过α-肾上腺素能受体的激活而增加，通过β-肾上腺素能受体的激活而降低。
