Author/Editor		Ikeda, H
Title		Mammalian retinal neurotransmitters: as seen through the eyes of a neurophysiologist
Type		članek
Source		Zdrav Vestn
Vol. and No.		Letnik 62, št. Suppl 1
Publication year		1993
Volume		str. 7-16
Language		eng
Abstract		The lecture considers the functional role of endogenous neurotransmitters in the mammalian retina, elucidated by the use of selective transmitter receptor antagonists in electrophysiological experiments. Firstly, the glutamatergic pathway which relays the visually-evoked excitation of the photoreceptors to the bipolar and the ganglion cells is discussed. Consideration is also given to an important role of NMDA receptors on the ganglion cells which are silent under normal physiological conditions, but become active in the presence of excessive glutamate, e.g. under ischaemic conditions. Secondly, the functional significance of GABAergic and glycinergic pathways which mediate visual inhibition of ON and OFF ganglion cells respectively, is considered. Reference is also made to the clinical relevance of benzodiazepine receptors linked with GABAA receptors. Thirdly, the dopaminergic pathways acting at different levels in the retina are reviewed. Finally, emphasis is placed on the interdependence and interactions between all these neurotransmitters, and on how normal retinal function depends upon a delicate balance, which is maintained by these neurochemical controls.
Descriptors		RETINAL GANGLION CELLS RECEPTORS, GLUTAMATE GLYCINE DOPAMINE BENZODIAZEPINES GABA MAMMALS