POLYAMINES MODULATE THE FUNCTION OF TRANSFECTED GLUTAMATE-RECEPTOR MGLUR1A

METABOTROPIC glutamate receptor mGluR1a was expressed in human embryon ic kidney 293 cells. 1S,3R-aminocyclopentane-1,3-dicarboxylic acid (1S ,3R-ACPD) stimulated dose-dependently, phosphoinositide (PI) hydrolysi s in transfected, but not in non-transfected cells. The polyamine sper mine did not affect PI hydrolysis in the absence of 1S,3 R-ACPD even a t a concentration of 1 mM, but it potentiated the stimulatory action o f 1S,3R-ACPD at 10 muM. The modulatory action of spermine was mimicked by spermidine but not by the short polyamine putrescine.