EFFECT OF AGING ON THE ACTIVITIES OF ACETYLCHOLINESTERASE, NA-ATPASE AND MG2+-ATPASE IN RAT PITUITARY AND HYPOTHALAMUS(,K+)

Acetylcholinesterase (AChE), Na+, K+-ATPase and Mg2+-ATPase activities were estimated in homogenised rat pituitary and hypothalamus of 4- an d 22-month-old rats. ACHE activity was not altered in the pituitary of aged compared to adult rats, while ft was found decreased by about 40 % in the hypothalamus. Na+,K+-ATPase activity remained stable in the h ypothalamus, while it was decreased by about 38% in the pituitary. Mg2 +-ATPase activity remained unchanged in the hypothalamus, but was incr eased by about 83% in the pituitary. This pituitary Na+, K+-ATPase ina ctivation may result in pathological mood and decreased neural excitab ility and metabolic energy production in aged animals. The age-related alterations of ACHE, Na+, K+-ATPase and Mg2+-ATPase activities may re flect changes in secretion and responses of some hormones of pituitary and hypothalamus.