Vanscheeuwijck P, Van de Velde E, Fraeyman N
J. F. & C. Heymans Institute of Pharmacology, University of Ghent Medical School, Belgium.
Biochem Pharmacol. 1990 Jun 15;39(12):2035-40. doi: 10.1016/0006-2952(90)90626-v.
The effect of aging on some of the properties of the beta-adrenergic transduction system was determined in a membrane fraction of spleen mononuclear leukocytes from young (2-3 months) and old (24-25 months) rats. Receptor density was unchanged and the percentage of receptors in the high affinity configuration for isoproterenol was reduced with increasing age. Adenylate cyclase activity, either unstimulated or stimulated with forskolin, GTP or isoproterenol was not affected by aging. This suggests the presence of compensatory mechanisms in the beta-adrenergic signal transduction system of rat spleen mononuclear cells in order to ensure equal cAMP production for equal agonist stimulation.
