Purification and structural analysis of hippocampal cholinergic neurostimulating peptide

• Published in: Brain research Vol. 572; no. 1-2; p. 164
• Main Authors: Ojika, K, Kojima, S, Ueki, Y, Fukushima, N, Hayashi, K, Yamamoto, M
• Format: Journal Article
• Language: English
• Published: Netherlands 14.02.1992
• Subjects: Amino Acid Sequence; Amino Acids - analysis; Animals; Antibodies, Monoclonal - immunology; Carboxypeptidases; Chromatography, Affinity; Chymotrypsin; Culture Techniques; Molecular Sequence Data; Nerve Tissue Proteins - chemistry; Nerve Tissue Proteins - isolation & purification; Neuropeptides - chemistry; Neuropeptides - isolation & purification; Peptide Hydrolases; Rats; Rats, Inbred Strains
• ISSN: 0006-8993
• DOI: 10.1016/0006-8993(92)90465-l

Hippocampal soluble fraction stimulates acetylcholine (AcCho) synthesis of medial septal nuclei in explant culture system. This stimulating activity was purified from 10-12-day-old rat hippocampus. During purification, the activity was separated into two fractions and a previously unreported peptide was purified from one fraction. The structure of this novel peptide is acetyl-Ala-Ala-Asp-Ile-Ser-Gln-Trp-Ala-Gly-Pro-Leu and we designated it as hippocampal cholinergic neurostimulating peptide (HCNP). Synthesized HCNP and de-acetylated HCNP (free-HCNP) stimulated AcCho synthesis of medial septal nuclei culture, in a dose-dependent manner, but not cultures of corpus striatum or anterior spinal cord. Mean half-maximal concentrations of HCNP and free-HCNP in AcCho synthesis of medial septal nuclei culture were 1.0 +/- 0.3 x 10(-10) M and 1.0 +/- 0.6 x 10(-11) M, respectively. Affinity purified polyclonal antibody to the free-HCNP neutralized the activity of crude hippocampal extract, as well as synthetic HCNP and free-HCNP. These observations suggested that HCNP was present in the hippocampal extract and was involved in development of specific cholinergic neuron in central nervous system.