Correlating physiology with gene expression in striatal cholinergic neurones

The expression of 34 transmitter-related genes has been examined in the cho linergic neurones of rat striatal brain slices, with the aim of correlating gene expression with functional activity. The mRNAs encoding types I, II/I IA, and III alpha subunits of the voltage-sensitive sodium channels were de tected, suggesting the presence of these three types of sodium channel. Sim ilarly, mRNAs: encoding all four alpha-amino-3-hydroxy-5-methylisoxazole-4- propionate (AMPA)-type glutamate receptor subunits and the NR1 and NR2A, 2B , and 2D subunits of the NMDA-type glutamate receptors were detected, sugge sting that various combinations of these subunits mediate the cellular resp onse to synaptically released glutamate. Other mRNAs detected included the NK1 and NK3 tachykinin receptors, all four known adenosine receptors, and t he GABA-synthesising enzyme glutamate decarboxylase, Subpopulations of thes e cholinergic neurones have been identified on the basis of the expression of the NK3 tachykinin receptor in 5% and the trkC neurotrophin receptor in 12% of the cells investigated.