[Effects and side effects of somatostatin]

Somatostatin, a peptide hormone with a wide range of actions, was first described in 1973. It is found in neurons of the central and peripheral nervous systems and D cells of the gut and pancreas. Somatostatin acts as a neurotransmitter, a local tissue factor, and a hormone. The intrinsic metabolic effects of somatostatin have been well investigated during the past 10 years. It inhibits the release of gastrointestinal secretions and delays the absorption of glucose and amino acids. Somatostatin inhibits the effects of the release of several of the hormones involved in water-electrolyte homeostasis. It exerts an influence on the regulation of several endocrine and exocrine functions, acting as a "shock absorber". In the nervous system somatostatin functions as a neurotransmitter; intrathecal application causes characteristic changes in the motor system and behavioral aberrations. Furthermore, it has been suggested that it may be a potent analgesic. Side-effects seen during animal experiments are many: marked increases in blood glucose, various behavioral changes, respiratory failure, and death. This article compares the effects and potential side-effects of somatostatin with particular regard to the recent observation that this substance may be a potent analgesic.