Intraventricular 6-hydroxydopamine increases the adrenal cortex mitotic activity in rats.
Effects of intraventricular injections of 6-hydroxydopamine (6-OHDA) on adrenocortical cell proliferation in rats have been investigated by means of the colchicine metaphase-arrest technique. In the group of animals receiving 6-OHDA alone, an increase of mean mitotic activity rate (MMAR) was observed at 96 h and 144 h after injection. This rise of MMAR was completely inhibited by pretreatment of animals with desmethylimipramine (DMI) - a blocker of norepinephrine uptake. It is concluded that enhancement of ACTH secretion is responsible for the above mentioned increase of mitotic activity after 6-OHDA administration. This phenomenon is related to abolition of the inhibitory noradrenergic effect on ACTH secretion by 6-OHDA treatment. Additionally, the results suggest little or no involvement of dopaminergic neurons in early changes of ACTH secretion after intraventricular 6-OHDA.
D000302:Adrenal Cortex / Q000187:drug effects*; D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D000818:Animals; D003891:Desipramine / Q000494:pharmacology; D006892:Hydroxydopamines / Q000008:administration & dosage / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D008938:Mitosis / Q000187:drug effects*; D016627:Oxidopamine; D051381:Rats; D011919:Rats, Inbred Strains
D006892:Hydroxydopamines; D016627:Oxidopamine; D000324:Adrenocorticotropic Hormone; D003891:Desipramine