Heterogeneous response in calcium signaling by adrenergic and cholinergic stimulation in cultured bovine trabecular cells.
Adrenergic and cholinergic drug-dependent Ca(2+)-signaling in cultured bovine trabecular cells was studied using a fluorescent calcium dye, fura-2, and digital video-imaging system. The resting calcium concentration in the cultured cell was 178.7 +/- 1.8 nM. Upon stimulation with norepinephrine, isoproterenol and carbachol trabecular cells responded heterogeneously. Many types of reaction to the stimuli were found; about 25% of the cells responded to the stimuli and about 30% showed no response to all of the stimuli. Carbachol induced response was blocked with pretreatment of atropine, and timolol inhibited the isoproterenol-induced response. Ca2+ signaling in trabecular cells may mediate the action of adrenergic and cholinergic drugs and possibly play significant roles in the regulation of intraocular pressure.
Department of Ophthalmology, Kyoto University Faculty of Medicine, Japan.
H
H
Tanihara
T
T
Ohuchi
N
N
Yoshimura
M
M
Negishi
S
S
Ito
D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002217:Carbachol / Q000494:pharmacology*; D002417:Cattle; D002478:Cells, Cultured; D016257:Fura-2 / Q000031:analogs & derivatives; D007545:Isoproterenol / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D014129:Trabecular Meshwork / Q000187:drug effects / Q000378:metabolism*
D000318:Adrenergic beta-Agonists; C049925:fura-2-am; D002217:Carbachol; D007545:Isoproterenol; D002118:Calcium; D016257:Fura-2; D009638:Norepinephrine