Tannenbaum G S
Neuropeptide Physiology Laboratory, McGill University, Montreal Children's Hospital Research Institute, P.Q., Canada.
Horm Res. 1988;29(2-3):70-4. doi: 10.1159/000180971.
Somatostatin plays an important role in the regulation of the episodic and ultradian rhythm of growth hormone (GH) secretion. Passive immunization of rats with specific antibodies to the 14 and 28 amino acid sequences caused a significant GH elevation. The fact that somatostatin antiserum was unable to block episodic GH surges indicates that this hormone's release must be regulated by a dual mechanism. Indeed, GH-releasing factor (GRF) seems to be instrumental in the maintenance of pulsatile GH secretion. Moreover, exogenous GRF induced a further GH increase predominantly during the period of active secretion. Neutralization of endogenous somatostatin eliminated this time-dependent effect, indicating that this peptide blocks periodical spontaneous GH release. Food deprivation and changes in glucose homeostasis virtually obliterate the ultradian GH rhythm. In this context, peripheral somatostatin seems to play an important role. Also the central GRF/somatostatin interplay is responsible for a short-loop feedback control on pituitary somatotrops.
生长抑素在调节生长激素（GH）分泌的间歇性和超日节律中起重要作用。用针对14和28个氨基酸序列的特异性抗体对大鼠进行被动免疫会导致GH显著升高。生长抑素抗血清无法阻断间歇性GH激增这一事实表明，该激素的释放必须由双重机制调节。事实上，生长激素释放因子（GRF）似乎在维持脉冲式GH分泌中起作用。此外，外源性GRF主要在活跃分泌期诱导GH进一步增加。内源性生长抑素的中和消除了这种时间依赖性效应，表明该肽阻断了周期性自发GH释放。食物剥夺和葡萄糖稳态的变化实际上消除了超日GH节律。在这种情况下，外周生长抑素似乎起重要作用。中枢GRF/生长抑素的相互作用也负责对垂体生长激素细胞的短环反馈控制。
