title: Cyclic AMP modulation of active ion transport in the pigmented rabbit conjunctiva.
abstract: This study was conducted to determine whether active ion transport in the pigmented rabbit conjunctiva was subjected to cyclic AMP modulation. 8-BrcAMP and compounds that may affect intracellular cAMP levels were tested for their effects on the conjunctival short-circuit current (Isc) following mucosal application. Conjunctival Isc was increased by 1 mM 8-BrcAMP, 0.001-20 microM forskolin, 0.01-2 mM theophylline, 2 microM 1-epinephrine, and 20 microM terbutaline in a Cl(-)-containing but not in a Cl(-)-free medium. The increase in Isc induced by 1 mM 8-BrcAMP was reversed by 1 mM N-phenylanthranilic acid, suggesting enhancement of Cl- secretion by cAMP. Similarly, the increase in Isc induced by 20 microM terbutaline was blunted by 1 microM timolol, suggesting a role for beta 2 adrenergic modulation of Cl- secretion. Collectively, these results are consistent with the notion of cAMP modulation of conjunctival active ion transport.
authors.affiliation: Department of Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, USA.
authors.forename: U B
authors.initials: UB
authors.lastname: Kompella
authors.forename: K J
authors.initials: KJ
authors.lastname: Kim
authors.forename: M H
authors.initials: MH
authors.lastname: Shiue
authors.forename: V H
authors.initials: VH
authors.lastname: Lee
mesh_terms: D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D001693:Biological Transport, Active; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002712:Chlorides / Q000378:metabolism*; D005576:Colforsin / Q000494:pharmacology; D003228:Conjunctiva / Q000187:drug effects / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism*; D004837:Epinephrine / Q000494:pharmacology; D017136:Ion Transport; D008297:Male; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D011817:Rabbits; D013726:Terbutaline / Q000494:pharmacology; D013806:Theophylline / Q000494:pharmacology
chemical_list: D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D002121:Calcium Channel Blockers; D002712:Chlorides; D010726:Phosphodiesterase Inhibitors; D005576:Colforsin; D015124:8-Bromo Cyclic Adenosine Monophosphate; D013806:Theophylline; D000242:Cyclic AMP; D013726:Terbutaline; D004837:Epinephrine