兔耳动脉中类固醇诱导的血管反应的细胞机制。

Cellular mechanisms of the steroid-induced vascular responses in the rabbit ear artery.

Miyahara H, Imayama S, Hori Y, Suzuki H

Department of Dermatology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.

Gen Pharmacol. 1993 Sep;24(5):1155-62. doi: 10.1016/0306-3623(93)90363-3.

Abstract

In anesthetized rabbits, topical application of dexamethasone to the ear produced an initial vasodilation followed by a vasoconstriction with long delay (120 min). Diphenhydramine inhibited the former, but not the latter. 2. In isolated rabbit ear arteries, dexamethasone reduced the amplitude of contractions of smooth muscles produced by nerve stimulation, noradrenaline and high-K solution, only at high concentrations (> 10(-5) M). 3. The initial vasodilation induced by topical application of dexamethasone may be related to endogenous histamine, while the delayed constriction response may not be direct actions of steroid to smooth muscles.

摘要

在麻醉的兔子中，将地塞米松局部应用于耳部会引起最初的血管舒张，随后是延迟较长时间（120分钟）的血管收缩。苯海拉明抑制前者，但不抑制后者。2. 在离体兔耳动脉中，地塞米松仅在高浓度（>10^(-5) M）时才会降低神经刺激、去甲肾上腺素和高钾溶液引起的平滑肌收缩幅度。3. 局部应用地塞米松引起的最初血管舒张可能与内源性组胺有关，而延迟的收缩反应可能不是类固醇对平滑肌的直接作用。