[The effects of adrenergic antagonists on epinephrine determined by the assay of adenosine 3',5'-monophosphate in bovine trabecular cells in vitro].
OBJECTIVE
To compare and assay the effects of various beta-adrenergic antagonists at effective concentrations on epinephrine (EPI).


METHODS
Cyclic adenosine 3',5'-monophosphate (cAMP) in trabecular cells was measured by protein binding assay with 3H-cAMP.


RESULTS
(1) The effect of EPI increasing cAMP in bovine trabecular cells (BTC) in vitro did not obviously recover at the fifth hour after the removal of 10(-5) mol/L timolol, and partly recovered at the fifth hour after the removal of 10(-6) mol/L timolol. (2) There was only part recovery for the effect of EPI at the fifth hour after the removal of ICI 118, 551 (10(-5) mol/L, and 10(-6) mol/L). (3) There was an obvious recovery for the effect of EPI at the fifteenth minute after the removal of 10(-5) mol/L bisoprolol.


CONCLUSIONS
The effect of timolol and ICI 118, 551 for blocking EPI is strong and sustained; bisoprolol produces a smaller blockade to the effect of EPI, lasting a short time. Our results also presume that BTC contains beta-adrenergic receptors, and beta 2-adrenergic receptors are dominant.
Lu
Y
Y
Department of Ophthalmology, Xuanwu Hospital, Beijing.
Li
M
M
Shen
Y
Y
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D017298:Bisoprolol / Q000494:pharmacology; D002417:Cattle; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism*; D004837:Epinephrine / Q000037:antagonists & inhibitors*; D011412:Propanolamines / Q000494:pharmacology; D013999:Timolol / Q000494:pharmacology; D014129:Trabecular Meshwork / Q000166:cytology / Q000378:metabolism*
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; C026777:ICI 118551; D013999:Timolol; D000242:Cyclic AMP; D017298:Bisoprolol; D004837:Epinephrine