Hypophyseal-Adrenocortical Role in Urinary Excretion of Epinephrine and Norepinephrine in Hypophysectomized and Adrenalectomized Rats

Experiments were designed to study the 24 hr urinary excretion of epinephrine and norepinephrine in hypophysectomized and adrenalectomized rats. One month after hypophysectomy there was a marked decline in urinary excretion of epinephrine. Norepinephrine excretion was greatly increased 15 days after hypophysectomy and one month after adrenalectomy. The hypophysectomized rats were also administered with 4 IU of ACTH daily for 23 days. After the 3rd injection of ACTH, epinephrine urinary excretion demonstrated a gradual increase. After the 14th injection, urinary epinephrine was not different statistically from control rats. ACTH treatment augmented urinary norepinephrine after the first injection but subsequent changes were insignificant. The volume of urine excreted declined markedly 1 month after hypophysectomy but this decline was not correlated with catecholamine excretion. ACTH administration also modified urinary volume in hypophysectomized rats to the level of control rats. The results suggest that ...