DISTRIBUTION OF HIPPOCAMPAL CHOLINERGIC NEUROSTIMULATING PEPTIDE (HCNP) IMMUNOREACTIVITY IN THE CENTRAL-NERVOUS-SYSTEM OF THE RAT

Hippocampal cholinergic neurostimulating peptide (HCNP), an undecapept ide isolated from the hippocampal tissue of young rats, enhances the c holinergic development in explant cultures of medial septal nuclei. Th is report concerns the distribution of HCNP immunoreactivity in the ce ntral nervous system (CNS) of 11- and 28-day-old Wistar rats; two affi nity-purified anti HCNP antibodies were used. Immunoblot analyses of e xtracts of different regions of the brain revealed a single 23 kDa ban d that corresponded to the presumed HCNP precursor protein. Immunostai ning of the various CNS structures of the 28-day-old rats was more int ense than in those of 11-day-old animals. HCNP immunoreactivity was de tected in neurons as well as in glia cells, particularly oligodendrogl ia. The perikarya of neurons in the cerebral cortex, hippocampus, limb ic cortex, caudate, putamen, arcuate nucleus of hypothalamus, trigemin al subnuclei, rostroventrolateral reticular nucleus and dorsal horn of the spinal cord were positively stained. in addition, nerve fibers an d terminals in the hypothalamic subnuclei, zona incerta, thalamic subn ucleus, caudate, putamen, locus coeruleus, trigeminal subnuclei, dorsa l motor nucleus of the vagus, dorsal horn of the spinal cord and inter mediolateral column also displayed HCNP immunoreactivity. These observ ations would suggest that HCNP and its related molecules may have mult ifunctional roles in the CNS.