Muscarinic acetylcholine receptor subtypes in human corneal epithelium and endothelium.
BACKGROUND
Muscarinic acetylcholine receptors are located throughout the body. The demonstration of muscarinic receptors in corneal tissue has been inconsistent. Using freshly fixed human corneal tissue, we show a complete profile of muscarinic receptor subtypes in human corneal epithelium and endothelium.


METHODS
Muscarinic receptor sites were studied using immunocytochemistry, immunofluorescence and immunoblotting.


RESULTS
Antibodies to M2, M4 and M5 muscarinic receptor subtypes bound in human corneal epithelium and endothelium. No binding was found for antibodies to M1 and M3 muscarinic receptor subtypes.


CONCLUSIONS
Our studies indicate the presence of M2, M4 and M5 muscarinic acetylcholine receptor subtypes in human corneal epithelium and endothelium. These receptors may play a role in the regulation of corneal homeostasis, other functions, like wound healing, or the pathogenesis of corneal diseases.
Grueb
Matthias
M
Department of Ophthalmology, University of Tuebingen, Schleichstr 12, D-72076, Tuebingen, Germany. matthias.grueb@med.uni-tuebingen.de
Reinthal
Eva
E
Rohrbach
Jens Martin
JM
Bartz-Schmidt
Karl Ulrich
KU
D000328:Adult; D000368:Aged; D015153:Blotting, Western; D004728:Endothelium, Corneal / Q000378:metabolism*; D019573:Epithelium, Corneal / Q000378:metabolism*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D043585:Receptor, Muscarinic M2 / Q000378:metabolism*; D043588:Receptor, Muscarinic M4 / Q000378:metabolism*; D043642:Receptor, Muscarinic M5 / Q000378:metabolism*
D043585:Receptor, Muscarinic M2; D043588:Receptor, Muscarinic M4; D043642:Receptor, Muscarinic M5