High affinity binding of L-glutamate to chick retinal membranes.
Binding of L-[3H]glutamate to membranes from whole chick retina and from subcellular fractions enriched with photoreceptor terminals (P1), or terminals from the inner plexiform layer (P2) was studied. Na+-dependent and Na+-independent binding to these membranes was demonstrated. Na+-independent binding was stereospecific. Kinetic analysis of the binding process indicated a single high-affinity system (KB = 0.55 micro M) with a capacity of approximately 20 pmoles/mg protein in all the membrane fractions. [3H]Glutamate binding to P1 and P2 fractions was effectively displaced by several structural analogues of glutamate. Glutamate diethyl-ester appreciably displaced binding, whereas kainic acid did not displace bound glutamate. Data indicate the binding of [3H]glutamate to physiologically relevant receptors in the chick retina.
D000818:Animals; D001667:Binding, Competitive; D002462:Cell Membrane / Q000378:metabolism; D002645:Chickens; D005971:Glutamates / Q000378:metabolism*; D018698:Glutamic Acid; D007700:Kinetics; D010786:Photoreceptor Cells / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000187:drug effects / Q000378:metabolism*; D017470:Receptors, Glutamate; D017981:Receptors, Neurotransmitter / Q000378:metabolism*; D012160:Retina / Q000378:metabolism*; D012964:Sodium / Q000494:pharmacology
D005971:Glutamates; D011956:Receptors, Cell Surface; D017470:Receptors, Glutamate; D017981:Receptors, Neurotransmitter; D018698:Glutamic Acid; D012964:Sodium