The effect of repeated electroconvulsive shocks (ECS) on growth hormone (GH) secretion was studied in rats. Male Sprague-Dawley animals were given one ECS daily for 10 days under halothane anaesthesia. Control animals were anaesthetised only. GH secretion was studied 24 h after the last ECS or sham procedure. Background GH secretion was significantly greater in ECS-treated than in sham-treated animals (P less than 0.001). The GH response to IV clonidine (0.01--0.1 mg/kg) did not differ between the two groups. The size of the GH response was not directly related to the basal GH secretion and could not be explained in terms of it.