Abstract | PURPOSE: METHODS: The effects of FP receptor agonists on contractility of bovine TM (BTM) were investigated using a force-length transducer. The effects of PGF2alpha on intracellular Ca2+ ([Ca2+]i) mobilization in cultured cells were measured using fura-2AM. The expression of the FP receptor protein was examined using Western blot analysis. RESULTS: The ET-1-induced (10(-8) M) contraction in isolated BTM was inhibited by PGF2alpha (10(-6) M) and fluprostenol (10(-6) M). This effect was blocked by FP receptor antagonists. Carbachol-induced contraction or baseline tension was not affected by PGF2alpha or fluprostenol. In cultured TM cells, ET-1 caused a transient increase in [Ca2+]i that was reduced by PGF2alpha. No reduction occurred in the presence of the FP receptor antagonist Al-8810. Western blot analysis revealed the expression of the FP receptor in native and cultured TM. CONCLUSIONS:
FP receptor agonists operate by direct interaction with ET-1-induced contractility of TM. This effect is mediated by the FP receptor. Thus, FP receptor agonists may decrease IOP by enhancing aqueous humor outflow through the TM by inhibiting ET-1-dependent mechanisms.
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Authors | Hagen Thieme, Christin Schimmat, Galina Münzer, Marianne Boxberger, Michael Fromm, Norbert Pfeiffer, Rita Rosenthal |
Journal | Investigative ophthalmology & visual science
(Invest Ophthalmol Vis Sci)
Vol. 47
Issue 3
Pg. 938-45
(Mar 2006)
ISSN: 0146-0404 [Print] United States |
PMID | 16505027
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Endothelin-1
- Receptors, Prostaglandin
- prostaglandin F2alpha receptor
- fura-2-am
- AL 8810
- Cloprostenol
- Dinoprost
- Calcium
- Fura-2
- Travoprost
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Topics |
- Animals
- Blotting, Western
- Calcium
(metabolism)
- Cattle
- Cells, Cultured
- Cloprostenol
(analogs & derivatives, pharmacology)
- Dinoprost
(analogs & derivatives, pharmacology)
- Endothelin-1
(antagonists & inhibitors, pharmacology)
- Fura-2
(analogs & derivatives, metabolism)
- Muscle Contraction
(drug effects)
- Muscle, Smooth
(physiology)
- Receptors, Prostaglandin
(agonists, antagonists & inhibitors)
- Trabecular Meshwork
(physiology)
- Travoprost
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