Regulation of H_1-receptor coupling and H_1-receptor mRNA by histamine in bovine tracheal smooth muscle

摘要

Pretreatment of bovine tracheal smooth muscle (BTSM) with histamine (1-100 μM, 1 h) induced a concentration-dependent desensitization of the contractile response to subsequently administered histamine, with a reduction of the maximum response of 72±8/100 (n = 5) following pre-exposure to 100 μM histamine. In contrast, concentration-response curves to the muscarinic agonist, methacholine were not affected following histamine pretreatment, indicating a homolgous desensitization. Furthermore, concentration-response curves to NaF, a G-protein activator were not altered following Histamine pre-incubation.