Abstract
1. Aging is a multivariate process which results from a progressive accumulation alterations including, for example, biochemical and physiological changes, in an organism with time. These alterations occur in short- and long-lived organisms, in invertebrates and vertebrates. 2. The present study demonstrates that the maximum responsiveness and sensitivity of dopamine-stimulated adenylate cyclase diminish with age as determinedin vitro in pedal ganglion homogenates. The dopamine-blocking efficacy of chlorpromazine also decreased with age in 4-year-old organisms compared to 1- and 2-year-old organisms. However, adenylate cyclase activity does not diminish with age in response to the GTP stable analogue, Gpp(NH)p. 3. The results suggest that one aspect of aging inMytilus edulis specifically affects dopamine interaction with this receptor-mediated system.