Antiserum to somatostatin reverses starvation-induced inhibition of growth hormone but not insulin secretion.
The role of SRIF in starvation-induced inhibition of GH and insulin secretion was assessed by passive immunization with anti-SRIF serum. Six-hour secretory profiles obtained from chronically cannulated male rats deprived of food for 72 h showed marked suppression of GH secretory bursts and significant depression of plasma insulin levels. Administration of 1 ml SRIF antiserum (SRIF AS) iv to starved rats resulted in rapid (within 15 min) restoration of high amplitude GH pulses (600-800 ng/ml) and sighificant elevation of GH trough values. The mean 6-h GH level of starved SRIF, AS-treated rats (189.2 +/- 23.9 ng/ml) was significantly higher than that of starved, normal sheep serum-treated control animals (62.8 +/- 5.8 ng/ml) (P less than 0.005). In contrast to the effects on GH, plasma insulin levels in starved rats administered SRIF AS remained low. No significant difference was observed in the mean 6-h plasma insulin level of starved-SRIF, AS-treated rats when compared to starved, normal sheep serum-treated controls. These findings suggest that circulating SRIF is a physiological regulator of starvation-induced GH suppression but is not involved in mediating the inhibition of insulin.
D000818:Animals; D000906:Antibodies; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D007106:Immune Sera; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D000078790:Insulin Secretion; D008297:Male; D051381:Rats; D013004:Somatostatin / Q000276:immunology / Q000502:physiology*; D013217:Starvation / Q000503:physiopathology*
D000906:Antibodies; D007106:Immune Sera; D007328:Insulin; D013004:Somatostatin; D013006:Growth Hormone