EXPRESSION OF THE OLFACTORY CYCLIC-NUCLEOTIDE GATED CHANNEL (CNG1) INTHE RAT-BRAIN

THE expression of the olfactory cyclic nucleotide-gated channel (CNG1) was studied in the rat brain. Using RT-PCR, levels of CNG1 mRNA were determined relative to the expression of a constantly expressed gene, ol-tubulin. RT-PCR showed that CNG1 mRNA was detectable in the pituita ry gland, the olfactory bulb, and the cerebellum of adult and 5-day-ol d rats. A 3.4 kb mRNA was detected in the olfactory bulb by Northern b lotting. In situ hybridization analysis showed that CNG1 mRNA expressi on is present in the olfactory bulb and in the Purkinje cells of the c erebellum. RT-PCR studies on Purkinje cell-enriched cultures obtained from the cerebellum of 16-day-old embryos (E16) confirmed the expressi on of CNG1 mRNA in these neurones. Our results show that CNG1 is not r estricted to the olfactory epithelium but is also present in specific regions of the brain. These results suggest that cyclic nucleotides ma y act in the regions that possess CNG1 gene expression to affect the e lectrical activity of certain neurones directly.