Retinal pigment epithelium in culture demonstrates a distinct beta-adrenergic receptor.
Retinal pigment epithelial (RPE) cells in culture, as well as freshly dissected embryonic RPE, exhibit a beta-adrenergic receptor. Agonist potency is: L-isoproterenol greater than (-)epinephrine greater than or equal to (-)norepinephrine much greater than dopamine. Propranolol blocks this effect. Hydroxybenzylpindolol (HYP), a beta-antagonist, also blocks the increase in cAMP elicited by L-isoproterenol. Binding of [125I]-hydroxybenzylpindolol, shows a half saturation concentration of 1.1 X 10(-9) M and 2.7 X 10(5) HYP binding sites per cell. The presence of such distinct beta-adrenergic responsiveness indicates a potentially important role for this receptor in RPE cell physiology.
D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D000242:Cyclic AMP / Q000378:metabolism; D004298:Dopamine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004837:Epinephrine / Q000494:pharmacology; D007545:Isoproterenol / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010869:Pindolol / Q000031:analogs & derivatives / Q000494:pharmacology; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism*
D011943:Receptors, Adrenergic, beta; C012357:hydroxybenzylpindolol; D010869:Pindolol; D000242:Cyclic AMP; D007545:Isoproterenol; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine