Effects of genistein, a tyrosine kinase inhibitor, on light adaptive cellular and synaptic plasticity in the outer retina of a teleost fish (carp)

Abstract

The effects of genistein, a protein tyrosine kinase inhibitor, on light adaptation-induced morphological (cellular and synaptic) plasticity were studied in the retina-eyecups of carp ( Cyprinus carpio ). In particular, the effects of genistein on the photomechanical movements of cones and the spinules of horizontal cells were quantitatively evaluated. The data suggested that genistein significantly blocked both light adaptive processes. It is concluded, therefore, that light adaptation of the teleost retina could involve activation of tyrosine kinases(s). This conclusion agrees with previous findings that multiple neuromodulators and protein kinases control retinal light adaptation. Keywords : Genistein, tyrosine kinase, light adaptation, plasticity, cone, photomechanical, movement, horizontal cell, spinules, retina, carp.