Wollheim C B, Blondel B, Renold A E, Sharp G W
Endocrinology. 1977 Sep;101(3):911-9. doi: 10.1210/endo-101-3-911.
The effects of somatostatin (SRIF) on glucagon release have been studied in the monolayer culture of newborn rat pancreas. It was found that SRIF inhibited glucagon release rapidly and in a dose dependent manner at concentrations of 1-1000 ng/ml. SRIF inhibited glucagon release under basal conditions and after stimulation by arginine, 3-isobutyl-1-methylxanthine (IBMX), high Ca++ concentrations, ionophore A23187 and Ca++, and Ba++. SRIF inhibited ionophore-induced glucagon release over 60 min when a low concentration of A23187 was used (0.1 microgram/ml) but not when a high concentraion (10 microgram/ml) was used. The stimulant effect of 10 microgram/ml A23187 was, however, inhibited by SRIF during short periods of incubation. The per cent inhibition of arginine-stimulated glucagon release due to SRIF remained unchanged when the Ca++ concentration in the medium was varied from 1-10 mM. It is concluded that SRIF promptly inhibits glucagon release under basal conditions or when stimulated by a variety of agents. Thus, the action of SRIF appears to be basic to the granule release process and not specifically antagonisitc to any particular stimulants. Further, as SRIF inhibits release due to raised cytosol Ca++ (e.g., ionophore-Ca++ or high Ca++ experiments) the action is probably at a late point in the release mechanism.
已在新生大鼠胰腺的单层培养物中研究了生长抑素（SRIF）对胰高血糖素释放的影响。结果发现，SRIF在1 - 1000 ng/ml的浓度下能迅速且呈剂量依赖性地抑制胰高血糖素的释放。SRIF在基础条件下以及在精氨酸、3 - 异丁基 - 1 - 甲基黄嘌呤（IBMX）、高钙浓度、离子载体A23187和钙离子及钡离子刺激后均能抑制胰高血糖素的释放。当使用低浓度的A23187（0.1微克/毫升）时，SRIF在60分钟内抑制离子载体诱导的胰高血糖素释放，但使用高浓度（10微克/毫升）时则不能。然而，在短时间孵育期间，SRIF可抑制10微克/毫升A23187的刺激作用。当培养基中的钙离子浓度在1 - 10 mM范围内变化时，SRIF对精氨酸刺激的胰高血糖素释放的抑制百分比保持不变。结论是，SRIF在基础条件下或受到多种试剂刺激时能迅速抑制胰高血糖素的释放。因此，SRIF的作用似乎是颗粒释放过程的基础，而不是对任何特定刺激物的特异性拮抗作用。此外，由于SRIF抑制因胞质溶胶钙离子升高（如离子载体 - 钙离子或高钙实验）引起的释放，其作用可能在释放机制的后期阶段。
