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.
Tanihara
H
H
Department of Ophthalmology, Kyoto University Faculty of Medicine, Japan.
Ohuchi
T
T
Yoshimura
N
N
Negishi
M
M
Ito
S
S
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