Adrenergic decentralization modifies the circadian rhythm of intraocular pressure

The effect of unilateral decentralization on the circadian rhythm of IOP was examined in rabbits to determine whether postganglionic sympathetic nerves to the eye can play a role in regulating the circadian rhythm of IOP in the absence of input from the central nervous system. Decentralization produced a marked reduction of the dark phase increase of IOP, but had little effect on IOP during the light phase. Therefore, circadian signals from the central nervous system, which contribute to the dark phase increase of IOP, arrive at the cervical ganglia by way of preganglionic fibers of the sympathetic chain and travel to the eye through postganglionic adrenergic nerves.