Glucagon: a stress hormone in the domestic fowl.

Chicks were injected intraperitoneally with glucagon (50 micrograms/kg) once daily for five days, beginning on the first day after hatching. At seven days of age the chicks were weighed and tissues sampled. Growth rate was unaffected, relative adrenal weight was increased and there were significant increases in adrenal cholesterol stores. The birds were hypoglycaemic, hypercholesteraemic but had a decreased concentration of corticosterone in the plasma. The results are consistent with the hypothesis that glucagon is a stress hormone and that it is responsible for activating the hypothalamo-hypophyseal-adrenocortical axis.