Histaminergic mechanisms in the vertebrate visual system.

This paper presents and summarizes our recent results on histamine (HI) in vertebrate visual system. The data include: 1. HI distribution, localization, synthesis, uptake and metabolism in retina, optic nerve, choroid and brain of carp, hen, rabbit, cow, 2. distribution of HI in human eyes, 3. 3H-mepyramine binding in the bovine retina, and HI dependent cAMP generating system in the rabbit eye, 4. effect of light stimulation on HI content in the rabbit retina, optic nerve and brain, 5. diurnal variations of histidine decarboxylase and histamine-methyltransferase activity in the rabbit ocular and brain structures. These results are discussed in terms of possible function(s) of HI in the visual system.