Effects of somatocrinin and a somatostatin antiserum on body and organ growth in the rat.

Chronic treatment with rGRF for 14 days with or without a specific antibody against somatostatin-14 were performed on 24-day old male Sprague-Dawley rats. Serum GH concentrations were significantly increased at the time of sacrifice while growth was not affected. rGRF, possibly through its effect on GH release, stimulated lung and kidney weights, increasing water content of the latter. Muscle and testes remained insensitive to GRF while the heart showed signs of reduced growth. Liver growth responded positively to the combined rGRF and ASS treatments whereas the pancreas exhibited loss of weight; on both of these organs, GH may act directly. The increased weights of gastric fundus and duodenum may result from an indirect action of GH on serum levels of gastrointestinal hormones such as gastrin. The results of this study stress the specific response of each organ to increased GH serum levels and indicate that their respective growth control factors cannot be generalized.