DISTRIBUTION OF NATRIURETIC PEPTIDE PRECURSOR MESSENGER-RNAS IN THE RAT-BRAIN

Atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and C-type natriuretic peptide (CNP) represent members of a recently disc overed neuropeptide family involved in central regulation of endocrine and autonomic functions. The present study employed an in situ hybrid ization approach to provide the first detailed. comparative mapping of ANP, BNP, and CNP mRNAs in brain. Results indicate that ANP mRNA is h ighly expressed in anterior olfactory nuclei, limbic cortices, dorsal endopiriform nucleus, hippocampal subfield CA1, cortical amygdaloid nu clei, medial habenula, anteroventral periventricular and arcuate nucle i, periventricular stratum, zona incerta, mammillary nuclei, inferior olive, nucleus ambiguus, and pontine paragigantocellular nuclei. CNP m RNA is expressed at highest levels in olfactory nuclei, limbic cortice s, dorsal endopiriform nucleus, hippocampal subfields CA1-3, anteroven tral periventricular and arcuate nuclei, and numerous brainstem region s (including the pontine, lateral reticular, solitary tract, prepositu s hypoglossal, and spinal trigeminal nuclei). Positive labeling for BN P mRNA was not observed in brain. The presence of both ANP and CNP mRN A in the same regions of distinct nuclei (e.g., the anteroventral peri ventricular and arcuate nuclei) suggests the potential for coexpressio n. Overall, the present data are consistent with a prominent role for both ANP and CNP in neuroendocrine regulation and central cardiovascul ar integration. The extensive localization of ANP and/or CNP mRNA in o lfactory nuclei, limbic cortex, hippocampus, amygdala and diencephalic limbic relays further indicate a putative role for ANP and CNP as neu romodulators of olfactory/limbic information processing. (C) 1995 Wile y-Liss, Inc.