Regional distribution of histamine in the brain of non-mammalian vertebrates

Abstract

The histamine contents in the brains of various species of non-mammalian vertebrates were determined by an HPLC-fluorometric method. the whole brain contents of histamine in birds (200–500 pmoles/g) were comparable to those in mammals, but were higher in reptiles (1000– pmoles/g) and amphibia (1600–2200 pmoles/g) and lower in teleosts (10–50 pmoles/g). In all species, histamine was unevenly distributed, being present at highest concentration in the diencephalon, except in teleosts, in which its content was highest in the telencephalon. The brain histamine contents were proportional to the reported densities of histamine-immunoreactive fibers.