title: Adrenomedullary catecholaminergic activity increases with age in male laboratory rodents.
abstract: In this report, we have examined the effects of aging on adrenomedullary catecholaminergic activity by evaluating the levels of activity of adrenal dopamine-beta-hydroxylase (DBH) in three species of laboratory rodents. Groups of male Fischer 344 rats (3-, 18-, and 28-month-old), Chinese hamsters (4- and 30-month-old), and Mongolian gerbils (3- and 26-month-old) were killed, and their adrenal DBH activities were measured by a sensitive radioenzymatic method. The results indicated that adrenomedullary DBH activities showed a progressive age-related increase in all three species investigated. Specifically, (a) adrenal DBH activity in the 18-month-old rats was significantly (p less than .001) higher than that of 3-month-old rats, and the enzyme activity in the 28-month-old rats was significantly (p less than .001) higher than that of the 18-month-old rats; (b) adrenal DBH activity in the 30-month-old hamsters showed a significant (p less than .001) increase over that found in the 4-month-old hamsters; and (c) DBH activity in the 26-month-old gerbils was significantly (p less than .05) higher than that noted in 3-month-old gerbils. These results suggest that an age-related increase in adrenal DBH activity may, at least in part, contribute to increased levels of circulating catecholamines.
mesh_terms: D000313:Adrenal Medulla / Q000201:enzymology*; D000375:Aging; D000818:Animals; D006224:Cricetinae; D003412:Cricetulus; D004299:Dopamine beta-Hydroxylase / Q000378:metabolism*; D005849:Gerbillinae; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D004299:Dopamine beta-Hydroxylase