Evidence for adenosine A2b receptors in the rat pineal gland.
We describe the effects of 5'-N-ethylcarboxamidoadenosine (NECA), a mixed A2a/A2b adenosine receptor agonist and 2-[p-(carboxyethyl)-phenylethylamino]-5'-N-ethylcarboxamidoaden osin e (CGS 21680), a selective A2a agonist, on cyclic AMP and N-acetylserotonin synthesis in rat pineal gland. NECA, 1 and 10 microM, increased cyclic AMP by 5- and 25-fold and N-acetylserotonin by 40- and 60-fold respectively, whereas CGS 21680 at the same concentrations was ineffective. These results argue for the presence of adenosine A2b receptors in rat pinealocytes.
Gharib
A
A
INSERM U352, INSA, Laboratoire de Chimie Biologique, Villeurbanne, France.
Delton
I
I
Lagarde
M
M
Sarda
N
N
D000241:Adenosine / Q000031:analogs & derivatives / Q000494:pharmacology; D019830:Adenosine-5'-(N-ethylcarboxamide); D000818:Animals; D000242:Cyclic AMP / Q000096:biosynthesis*; D009924:Organ Culture Techniques; D010627:Phenethylamines / Q000494:pharmacology; D010870:Pineal Gland / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D011983:Receptors, Purinergic / Q000378:metabolism*; D012701:Serotonin / Q000031:analogs & derivatives* / Q000096:biosynthesis
D010627:Phenethylamines; D011983:Receptors, Purinergic; C061282:2-(4-(2-carboxyethyl)phenethylamino)-5'-N-ethylcarboxamidoadenosine; D012701:Serotonin; D019830:Adenosine-5'-(N-ethylcarboxamide); D000242:Cyclic AMP; D000241:Adenosine; C006389:N-acetylserotonin