Adenosine actions and adenosine receptors after 1 week treatment with caffeine.
After one week treatment with caffeine (20 mg/kg i.p.) the number of adenosine receptors, as determined by specific binding of (3H)-L-PIA, in rat cerebral cortical membranes was increased by about 25%. Cyclic AMP accumulation induced by adenosine analogues in slices of rat hippocampus was unaffected by caffeine treatment. The inhibition of lipolysis in rat fat cells by 2-chloro-adenosine was similarly unaffected. The potency of caffeine as an antagonist of these adenosine-receptor mediated effects was not altered by caffeine treatment. It is concluded that at least some adenosine receptors are up-regulated as a consequence of prolonged caffeine treatment, but that the increase in receptor number is not related to changes in at least two effects of adenosine and caffeine.
D000241:Adenosine / Q000031:analogs & derivatives / Q000494:pharmacology*; D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D002110:Caffeine / Q000494:pharmacology*; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006624:Hippocampus / Q000378:metabolism; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000187:drug effects* / Q000378:metabolism; D011983:Receptors, Purinergic; D013997:Time Factors
D011956:Receptors, Cell Surface; D011983:Receptors, Purinergic; D002110:Caffeine; D000242:Cyclic AMP; D000241:Adenosine