Relationship of melanocyte-stimulating hormone to photoreceptor damage.
Three separate experiments involving intact, sham-operated and hypophysectomized albino rats, examined the relationship of alpha-MSH to the severity of photically-induced retinal damage. alpha-MSH was administered at 1430 hours and 0900 hours, when endogenous MSH levels are different, and continuously by osmotic minipumps. alpha-MSH was ineffective in enhancing or reducing photoreceptor damage under these experimental conditions. A highly significant reduction in outer nuclear layer and total retinal thicknesses occurred in intact and hypophysectomized rats exposed to continuous illumination as compared to those in cyclic photoperiod. Hypophysectomy provided a significant degree of protection to the retina from photic damage.
D000818:Animals; D005260:Female; D007016:Hypophysectomy; D009074:Melanocyte-Stimulating Hormones / Q000494:pharmacology*; D009900:Optic Nerve / Q000187:drug effects / Q000502:physiology; D010786:Photoreceptor Cells / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D012160:Retina / Q000187:drug effects / Q000502:physiology
D009074:Melanocyte-Stimulating Hormones