Adrenal demedullation and peripheral 6-OHDA administration in the rabbit: effects on body weight, general activity and cardiovascular responsivity.

Two experiments were undertaken to determine the effects of systemic 6-hydroxydopamine (6-OHDA) administration and adrenal enucleation on body weight, brain and heart norepinephrine, general activity, and cardiovascular responsivity in the rabbit. 6-Hydroxydopamine produced long lasting, dose related decreases in baseline blood pressure (BP) and in pressor responses following electric shock. Partial reversal of the BP changes was observed in nonenucleated animals tested 20 days after 6-OHDA administration but not in enucleated animals tested 5, 10 or 20 days post-injection or in control animals tested 5, 10 or 15 days after vehicle injection. Although 6-OHDA administration produced transient weight loss and activity decrements, no long term weight or activity changes were observed.