From the Maurice and Gabriela Goldschleger Eye Institute and the Department of Physiology and Pharmacology Sackler School of Medicine, Tel-Aviv University Ramat Aviv, Israel
Abstract:
Administration of somatostatin intracerebroventricularly to mice produced a dose-dependent mydriasis, whereas intravenous injections were ineffective. Naloxone could prevent or abolish this effect. It is suggested that somatostatin either directly excites opiate receptors or activates endopioid pathways involved in the regulation of pupillary size.