COMPARISON OF NEURONAL INOSITOL 1,4,5-TRISPHOSPHATE 3-KINASE AND RECEPTOR MESSENGER-RNA DISTRIBUTIONS IN THE HUMAN BRAIN USING INSITU HYBRIDIZATION HISTOCHEMISTRY

The distribution of the messenger RNA coding for the recently cloned i nositol 1,4,5-trisphosphate (InsP3) 3-kinase, the enzyme phosphorylati ng InsP3 to InsP4, was compared to the localizations of InsP3 receptor mRNA in the human brain using in situ hybridization histochemistry an d oligonucleotide probes. InsP3 3-kinase and receptor mRNA levels were high in the cerebellar Purkinje cells. They were also observed, to a much lesser degree than in the cerebellum, in the hippocampal CA1 pyra midal cells and dentate gyrus granule cells, in the majority of the co rtical neurons and in the striatal medium-sized neurons. Both mRNAs we re not detected in the brainstem and in the glial cells.