Effects of riboflavin deficiency upon age-related changes in beta-adrenergic and adenosine receptor binding in rat adipocytes.
The binding of (-)(3H)dihydroalprenolol (DHA) and (-)-N6-(3H)phenyl-isopropyladenosine (PIA) to beta-adrenergic and adenosine receptors, respectively, was determined in membranes of adipocytes isolated from riboflavin-deficient rats and age-matched, pair-fed controls for feeding periods of three to forty weeks. In normal chow-fed animals, the binding of both ligands to receptors markedly decreased in older compared to that in younger animals. In young, riboflavin-deficient animals, DHA binding diminished compared to that in age-matched controls. No further decrease in binding of DHA occurred in older, aged-matched, riboflavin-deficient rats. Riboflavin deficiency did not have any effect on PIA binding in either young or old animals. Thus, in riboflavin deficiency, beta-adrenergic binding in adipocyte membranes from young animals is reduced and the normal age-related decrease in this receptor binding does not occur. By contrast, the binding of PIA to adenosine receptors is lower in older than in younger animals regardless of riboflavin nutriture.
Dutta
P
P
Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.
Pinto
J
J
Rivlin
R
R
D000273:Adipose Tissue / Q000378:metabolism* / Q000473:pathology; D000375:Aging / Q000378:metabolism*; D000818:Animals; D004082:Dihydroalprenolol / Q000378:metabolism; D004912:Erythrocytes / Q000201:enzymology; D005260:Female; D005980:Glutathione Reductase / Q000097:blood; D009929:Organ Size; D010660:Phenylisopropyladenosine / Q000378:metabolism; D051381:Rats; D011943:Receptors, Adrenergic, beta / Q000378:metabolism*; D011983:Receptors, Purinergic / Q000378:metabolism*; D012257:Riboflavin Deficiency / Q000378:metabolism* / Q000473:pathology
D011943:Receptors, Adrenergic, beta; D011983:Receptors, Purinergic; D010660:Phenylisopropyladenosine; D004082:Dihydroalprenolol; D005980:Glutathione Reductase