Stimulation and inhibition of lipolysis in isolated rat adipocytes: evidence for age-related changes in responses to forskolin and PGE1.

摘要: The ability of a number hormones to activate cellular responses in variety cells declines with age. mechanisms responsible for these alterations are complex and incompletely understood. Rat adipocytes have served as an important model study blunted stimulatory which function by activating cAMP accumulation. We previously found that the lipolytic response from older rats beta adrenergic receptor agonist isoproterenol appeared be due lessened Further, was apparently caused accentuated inhibition lipolysis, mediated adenosine receptors activated endogenously released adenosine. present studies were designed test extend those conclusions. utilized forskolin augment accumulation occurs presence isoproterenol. Isoproterenol-activated lipolysis greater 2 month old compared 12 (603 +/- 32 vs 450 29 nmol/10(5) cells/hr, P less than 0.01). However, (10(-6) M), there no significant difference between two groups (646 23 615 nmoles/10(5) cells/hr). As we had seen previously, phenylisopropyladenosine more effectively inhibited rats. now also find PGE1 efficaciously inhibits These data confirm diminished appears rate-limiting alteration regulation lipolysis.(ABSTRACT TRUNCATED AT 250 WORDS)