The capsaicin-induced inflammatory reaction in the cat eye: antagonism by ruthenium red.
The neurogenic ocular inflammatory response in the cat was investigated by means of intracameral injections of capsaicin. At a dose of 200 micrograms intracamerally the eye responded with a breakdown of the blood-aqueous barrier (BAB) and a transient ocular hypertension. A response of the same magnitude was observed when a dose of 1 microgram capsaicin was given. Most of the response to this lower dose was prevented by ruthenium red, an inorganic dye thought specifically to antagonize the effects of capsaicin on sensory nerve endings. Following injection of 200 micrograms capsaicin there was a transient increase in pupil size, but this response was not seen after 1 microgram. Repeated injections of 200 micrograms capsaicin when the effects of the first dose had vanished resulted in tachyphylaxis of the mydriatic response. A dose of 200 micrograms of capsaicin had no effect on resistance in the outflow routes for aqueous humour.
Andersson
S E
SE
Department of Physiology and Medical Biophysics, University of Uppsala, Sweden.
Almegård
B
B
D000818:Animals; D001082:Aqueous Humor / Q000378:metabolism; D001693:Biological Transport, Active / Q000187:drug effects; D002211:Capsaicin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002415:Cats; D009877:Endophthalmitis / Q000139:chemically induced*; D005260:Female; D007429:Intraocular Pressure / Q000187:drug effects; D008297:Male; D011680:Pupil / Q000187:drug effects; D012430:Ruthenium Red / Q000494:pharmacology*
D012430:Ruthenium Red; D002211:Capsaicin