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Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye
Published on: June 20, 2015
Antimuscarinic action of oxymetazoline on human intraocular muscles
Popat N Patil1, Hitoshi Ishikawa
1Division of Pharmacology, College of Pharmacy, Ohio State University, Columbus, OH., USA.
Abstract:
At 10 microM or 100 microM concentration of oxymetazoline, the activity of carbachol was competitively blocked on the isolated human iris sphincter or ciliary muscles. On the ciliary muscle, the dissociation constant K(B) of 5.2 microM was obtained. The value is approximately equal to that on the iris sphincter. Even though it is a weakly active antimuscarinic drug with potent alpha-adrenoceptor-mediated vasoconstriction activity, the therapeutic benefit in ocular decongestion recovery may be partly related to the weak anticholinergic activity.
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