Cooperative interactions at [3H]kainic acid binding sites in rat and human cerebellum.
Inhibition of the specific binding of [3H]kainic acid was studied in membranes isolated from rat and human cerebellum; the sequence of potencies in both species were: kainic acid greater than L-glutamic acid greater than dihydrokainic acid greater than D-glutamic acid. Whereas the Hill coefficient for unlabelled Kainate was 1.0, dihydrokainic acid and D- and L-glutamic acids exhibited negative cooperativity with Hill coefficients of near 0.5. This allosteric interaction of glutamic acid at the kainic acid recognition site suggests a biochemical correlate for the synergistic effects of these compounds in vivo.
D000818:Animals; D002531:Cerebellum / Q000378:metabolism*; D005971:Glutamates / Q000378:metabolism*; D006801:Humans; D007608:Kainic Acid / Q000031:analogs & derivatives / Q000378:metabolism*; D008297:Male; D011759:Pyrrolidines / Q000378:metabolism*; D051381:Rats; D011955:Receptors, Drug / Q000378:metabolism*
D005971:Glutamates; D011759:Pyrrolidines; D011955:Receptors, Drug; C020889:dihydrokainic acid; D007608:Kainic Acid