title: Control of rod shedding in the frog retina.
abstract: In all vertebrate species examined thus far, rod outer segment shedding follows a cyclic pattern in which the outer segment tips are shed shortly after the onset of light. Work in the rat retina suggests that rod shedding may follow a circadian rhythm which is controlled by one or more circadian oscillators. Our results in the frog retina are significantly different in that: rod shedding can be driven by the onset of light or other environmental cues; shedding does not persist in constant darkness; shedding is unaffected in frogs with chronic unilateral or bilateral optic nerve section; and shedding will rapidly phase shift to the time of light onset on a wide variety of diurnal cycles. Thus, rod shedding in the frog retina does not appear to be a classical circadian rhythm.
authors.affiliation: Cullen Eye Institute Baylor College of Medicine Houston, Texas 77030 U.S.A.
authors.forename: S F
authors.initials: SF
authors.lastname: Basinger
authors.forename: J G
authors.initials: JG
authors.lastname: Hollyfield