Desautels M, Wollin A, Halvorson I, Muralidhara D V, Thornhill J
Department of Physiology, College of Medicine, University of Saskatchewan, Saskatoon, Canada.
Am J Physiol. 1994 Mar;266(3 Pt 2):R831-7. doi: 10.1152/ajpregu.1994.266.3.R831.
Electrical stimulation of the ventromedial hypothalamic area in rats caused a significant but transient increase in interscapular brown adipose tissue temperature. This response was markedly reduced by cimetidine, a histamine H2-receptor antagonist, but not by pyrilamine, an H1-receptor antagonist. Histamine is present in substantial amounts within mast cells in brown adipose tissue as injections of compound 48/80, which cause degranulation of connective tissue mast cells, reduced the tissue histamine content by > 85%. In contrast, histamine content in brown adipose tissue was not affected by loss of sympathetic neural input (with 6-hydroxydopamine) or sensory neural input (with capsaicin). Neither cimetidine nor histamine had any effect on basal and norepinephrine-stimulated rates of O2 consumption by isolated brown adipocytes. These results indicate that histamine released from mast cells acting on H2-receptors may play an important but indirect role in the thermogenic response of brown adipose tissue to stimulation of the ventromedial hypothalamic area.
对大鼠腹内侧下丘脑区域进行电刺激，可使肩胛间棕色脂肪组织温度显著但短暂升高。组胺H2受体拮抗剂西咪替丁可显著减弱这一反应，但H1受体拮抗剂吡苄明则无此作用。棕色脂肪组织的肥大细胞内存在大量组胺，因为注射可使结缔组织肥大细胞脱颗粒的化合物48/80，可使组织组胺含量降低85%以上。相比之下，棕色脂肪组织中的组胺含量不受交感神经输入丧失（用6-羟基多巴胺）或感觉神经输入丧失（用辣椒素）的影响。西咪替丁和组胺对分离的棕色脂肪细胞的基础氧消耗率和去甲肾上腺素刺激的氧消耗率均无影响。这些结果表明，肥大细胞释放的组胺作用于H2受体，可能在棕色脂肪组织对腹内侧下丘脑区域刺激的产热反应中起重要但间接的作用。
