In two groups of adult rabbits (n=40) on background of chronic stress, induced by intravenous injections of adrenalin for 3 months, we produced a model of high intraocular pressure (IOP). In the group I melatonin (M) wasn’t used; in the group II — by 0.3 mg M as a water suspension was used per os for 4 months before, during and after induction of the model. Circadian fluctuation of eye hydrodynamics and IOP with maximal level in the morning hours were noted. In the group I — progressive disturbances of aqueous humor (AH) dynamics and essential elevation of IOP were noted. In the group II a significant change in eye hydrodynamic system wasn’t revealed. Slightly increased IOP in early period of the experiment was normalized in late period. M might be considered as an adaptive and stress-protective agent for disturbances of circadian regulation of IOP.
