Previous studies suggest that α1-adrenergic (α1-AR)-induced intracellular calcium ([Ca2+](i)) mobilization in rat parotid acinar cells declines with age. In this study, we examined the effects of food restriction on α1-AR- and muscarinic-stimulated [Ca2+](i) mobilization in parotid acinar cells during aging. [Ca2+](i) levels in response to the α1-AR agonist epinephrine and the muscarinic agonist carbachol were evaluated in Fura-2-loaded parotid acinar cells from ad libitum-fed (AL) and food- restricted (FR) Fischer 344 malt rats at 4, 6, 14, and 24 months of age. [Ca2+](i) responses to epinephrine and carbachol (10 μM) were significantly reduced (48% and 35%, respectively; p < .05) in cells from 24- month-old AL rats as compared to younger AL rats. In contrast, no significant reduction of epinephrine and carbachol responses was observed in 24-month- old FR animals. An age-related increase in basal [Ca2+](i) (peak around 14 months; p <. 02) was observed in both AL and FR rats. In addition, basal [Ca2+](i) was higher in FR than in AL rats at 14 and 24 months of age (p < .02). These studies suggest that FR partially attenuates or delays age- related impairments in α1-AR- and muscarinic-cholinergic signal transduction systems of parotid acinar cells. Basal [Ca2+](i) also appears to be altered during aging and by FR.
|Original language||English (US)|
|Journal||Journals of Gerontology - Series A Biological Sciences and Medical Sciences|
|State||Published - 1997|
ASJC Scopus subject areas
- Geriatrics and Gerontology