Effects of Timolol, Epinephrine, and Acetozolomide on Aqueous Flow during Sleep
نویسندگان
چکیده
The effects of timolol, epinephrine, and acetazolamide on the rate of flow of aqueous humor through the anterior chamber of awake and sleeping human subjects was studied. Timolol reduced the rate in awake subjects but not sleeping subjects. Epinephrine increased the rate in sleeping subjects to a greater extent than in awake subjects. Acetazolamide reduced the rate of flow in awake subjects or epinephrinestimulated subjects. Acetazolamide reduced the rate of flow slightly below the basal rate observed during sleep, but the reduction was small and not statistically significant. The authors propose that the diurnal fluctuation of the rate of aqueous humor flow in humans is driven by changes in the concentration of endogenous epinephrine available to the ciliary epithelia. Invest Ophthalmol Vis Sci 26:1315-1319, 1985
منابع مشابه
The effect of topical timolol on epinephrine-stimulated aqueous humor flow in sleeping humans.
PURPOSE It has been shown that intravenously administered epinephrine can increase the rate of aqueous humor flow in sleeping humans. This experiment was conducted to determine if this stimulatory effect can be blocked by the beta-adrenergic antagonist timolol. METHODS Twenty normal human subjects were studied for one sleep cycle at night. Epinephrine was infused intravenously at a rate of 1 ...
متن کاملEffects of timolol, epinephrine, and acetazolamide on aqueous flow during sleep.
The effects of timolol, epinephrine, and acetazolamide on the rate of flow of aqueous humor through the anterior chamber of awake and sleeping human subjects was studied. Timolol reduced the rate in awake subjects but not sleeping subjects. Epinephrine increased the rate in sleeping subjects to a greater extent than in awake subjects. Acetazolamide reduced the rate of flow in awake subjects or ...
متن کاملThe pathophysiological effects of nitrogen mustard on the rabbit eye. II. The inhibition of the initial hypertensive phase by capsaicin and the apparent role of substance P.
hovers near venous pressure. A study of glaucoma patients, in whom intraocular pressure is much higher, might yield different results. It appears that aand /3-adrenergic drugs have effects on the ciliary body in its production of aqueous humor. Beta antagonists seem to decrease aqueous formation, and beta agonists seem to increase formation. Unblocked alpha agonists appear to decrease aqueous f...
متن کاملPharmacokinetic basis for nonadditivity of intraocular pressure lowering in timolol combinations.
The authors determined whether the ocular absorption of topically applied timolol in the pigmented rabbit was affected significantly by coadministration with either pilocarpine or epinephrine in the same drop to explain the nonadditivity in intraocular pressure lowering (IOP) seen clinically. They instilled 25 microliters of 0.65% timolol maleate solution (equivalent to 0.5% timolol), both in t...
متن کاملEffect of chronic epinephrine on aqueous humor flow during the day and during sleep in normal healthy subjects.
Epinephrine 2% drops were administered to one eye and a placebo to the fellow eye twice a day for 2 weeks in 18 normal human volunteers. The circadian rhythm of aqueous humor flow was measured by fluorophotometry. Epinephrine (compared with placebo) had no measurable effect on the rate of aqueous flow or the circadian rhythm of aqueous humor flow. These results suggest either that topical appli...
متن کامل