Mitsuma T, Nogimori T, Sun D H, Chaya M
Horm Res. 1986;23(2):99-105. doi: 10.1159/000180296.
The effects of histamine (HA) and related compounds on thyrotropin-releasing hormone (TRH) and thyrotropin (TSH) secretion in rats were studied. Histidine (1.0 g/kg), HA (5.0 mg/kg) or histamine antagonists mepyramine (MP) (100 mg/kg) or famotidine (FA) (5.0 mg/kg) were injected intraperitoneally, and the rats were decapitated at various intervals after the injection. The hypothalamic immunoreactive TRH (ir-TRH) content increased significantly after histidine or HA injection, decreased significantly after FA injection, but was not changed by MP. The plasma ir-TRH concentration did not change significantly after injection of these drugs. The plasma TSH levels decreased significantly in a dose-related manner after histidine or HA injection and increased significantly in a dose-related manner after FA injection. The plasma thyroid hormone levels showed no changes. In the FA-pretreated group, the inhibitory effect of histidine or HA on TSH levels was prevented, but not in the MP-pretreated group. The plasma ir-TRH and TSH responses to cold were inhibited by histidine or HA and enhanced by FA. The plasma TSH response to TRH was inhibited by histidine or HA and enhanced by FA. The inactivation of TRH immunoreactivity by hypothalamus or plasma in vitro after histidine, HA, MP or FA was not different from that of the control. These findings suggest that histamine may act both on the hypothalamus and the pituitary to inhibit TRH and TSH release, and that its effects may be mediated via H2-receptor.
研究了组胺（HA）及相关化合物对大鼠促甲状腺激素释放激素（TRH）和促甲状腺激素（TSH）分泌的影响。腹腔注射组氨酸（1.0 g/kg）、HA（5.0 mg/kg）或组胺拮抗剂美吡拉敏（MP）（100 mg/kg）或法莫替丁（FA）（5.0 mg/kg），注射后在不同时间间隔将大鼠断头。注射组氨酸或HA后，下丘脑免疫反应性TRH（ir-TRH）含量显著增加，注射FA后显著降低，但MP对其无影响。注射这些药物后，血浆ir-TRH浓度无显著变化。注射组氨酸或HA后，血浆TSH水平呈剂量依赖性显著降低，注射FA后呈剂量依赖性显著升高。血浆甲状腺激素水平无变化。在FA预处理组中，组氨酸或HA对TSH水平的抑制作用被阻断，但在MP预处理组中未被阻断。组氨酸或HA抑制，FA增强了血浆ir-TRH和TSH对寒冷的反应。组氨酸或HA抑制，FA增强了血浆TSH对TRH的反应。组氨酸、HA、MP或FA处理后，下丘脑或血浆体外对TRH免疫反应性的失活与对照组无差异。这些发现表明，组胺可能作用于下丘脑和垂体，抑制TRH和TSH的释放，其作用可能通过H2受体介导。
