Further studies on histamine-stimulated catecholamine secretion from cultured bovine adrenal medullary cells

• Published in: Japanese Journal of Pharmacology 1988, Vol.46 (suppl), p.148-148
• Main Authors: Yasuko Ishimura, Atsushi Nakanishi, Mir Misbahuddin, Kyoji Morita, Motoo Oka
• Format: Article
• Language: Japanese
• ISSN: 0021-5198

Histamine is known to stimulate the secretion of catecholamine (CA) from adrenal medulla through its effect on splanchnic nerve or its direct effect on the adrenal medulla . In the present study, we examined the effect of histamine on CA secretion from cultured bovine adrenal medullary cells. Cultured cells were first incubated for 30 min in the presence of ouabain(1 μM), and then stimulated with histamine. The incubation medium containing histamine was renewed every 2 min, and CA secreted from the cells during these 2 min periods was measured. The secretion of CA stimulated by histamine was maximal during the first 2 min period, and then decreased with the time. After about 10 min, CA secretion had reached a basal level although histamine was The stimulation of CA secretion was detectable at concentrations higher than present . 100 nM of histamine and maximal at concentration of 10 μM. The secretion of CA by histamine was dependent on the presence of Ca^2+ in the medium, and was inhibited by diphenhydramine(H_1 -receptor blocker) , but not by cimetidine(H_2 -receptor blocker) . ACh could stimulate the secretion of CA from the cells which had become insensitive to Conversely, histamine stimulated CA secretion from the cells which had histamine . become insensitive to ACh. These results suggest that the mechanism of CA secretion by histamine is different from that by ACh.