Scanes C G, Harvey S
Department of Animal Sciences, Rutgers State University, New Brunswick, New Jersey 08903.
Gen Comp Endocrinol. 1989 Aug;75(2):256-64. doi: 10.1016/0016-6480(89)90078-6.
The present communication examines the influence of somatostatin (SRIF14) on basal and thyrotropin-releasing hormone (TRH)- or growth hormone-releasing factor (GRF)-induced GH secretion in young (6 week old) and adult male chickens. Studies were performed in sodium pentobarbitone-anesthetized chickens where basal plasma concentrations of GH are low and both TRH and GRF consistently stimulate GH release. In both young and adult chickens, basal GH secretion was reduced by SRIF14 infusion (3 micrograms/kg/min). Similarly, in adult and young birds, the GH secretory response to a challenge with a GRF bolus (10 micrograms/kg) was inhibited by the concomitant intravenous infusion of SRIF14 (0.3 or 3.0 micrograms/kg/min). In adult chickens, the GH response to TRH (10 micrograms/kg) was suppressed (by 93%) by SRIF14 infusion (3 micrograms/kg/min) and tended to be inhibited (by 29%) by a lower dose of SRIF14 (0.3 micrograms/kg/min). In contrast, in young chicks, GH release following TRH challenge (either 1 or 10 micrograms/kg) was only partially inhibited by SRIF14 infusion (3 micrograms/kg/min). The response to a TRH challenge (10 micrograms/kg) was unaffected by the low dosage of SRIF14 infusion (0.3 micrograms/kg/min). It is concluded that SRIF14 inhibits both GRF- and TRH-stimulated GH release in young and adult chickens.
本报告研究了生长抑素（SRIF14）对6周龄幼龄和成年雄性鸡基础状态以及促甲状腺激素释放激素（TRH）或生长激素释放因子（GRF）诱导的生长激素（GH）分泌的影响。实验在戊巴比妥钠麻醉的鸡身上进行，此时基础血浆GH浓度较低，TRH和GRF均能持续刺激GH释放。在幼龄和成年鸡中，输注SRIF14（3微克/千克/分钟）均可降低基础GH分泌。同样，在成年和幼龄鸡中，静脉同时输注SRIF14（0.3或3.0微克/千克/分钟）可抑制GRF推注（10微克/千克）激发的GH分泌反应。在成年鸡中，输注SRIF14（3微克/千克/分钟）可抑制（93%）对TRH（10微克/千克）的GH反应，低剂量SRIF14（0.3微克/千克/分钟）则倾向于抑制（29%）该反应。相比之下，在幼雏中，SRIF14输注（3微克/千克/分钟）仅部分抑制TRH激发（1或10微克/千克）后的GH释放。低剂量SRIF14输注（0.3微克/千克/分钟）对TRH激发（10微克/千克）的反应无影响。得出的结论是，SRIF14抑制幼龄和成年鸡中GRF和TRH刺激的GH释放。
