[Histochemical study of the cholinesterases of various formations of the vertebrate endbrain].

Histochemical studies have been made on true (AChE) and false (BChE) cholinesterases in different parts of the telencephalon of amphibians, reptiles and mammals. The data obtained indicate that the enzymic localization depends on both the level of the development of the brain and phylogenetic age of its individual formations. In the telencephalon of Ambystoma mexicanum, high concentration of AChE was found in vascular-capillary network, in other investigated amphibians (Triturus vulgaris, Rana temporaria) diffuse distribution of AChE of different intensity was observed in ancient formations of the telencephalon (septum and striatum). In reptiles (Eremias arguta, Testudo horsfieldi) undifferentiated diffuse AChE reaction is predominant in ancient parts of the cortex (septum excluded), whereas differentiated cytoplasmic localization is typical of the old and new cortex. In the brain of the lizard high BChE activity was found in the conducting pathways. Mammalian brain (rabbit, guinea pig) exhibits differentiated AChE and BChE reactions in the old and new cortex.