K. Ojika et al., DEMONSTRATION OF DEACETYLATED HIPPOCAMPAL CHOLINERGIC NEUROSTIMULATING PEPTIDE AND ITS PRECURSOR PROTEIN IN RAT-TISSUES, Brain research, 701(1-2), 1995, pp. 19-27
This report concerns the demonstration of hippocampal cholinergic neur
ostimulating peptide (HCNP), its deacetylated analogue (free HCNP) and
HCNP precursor protein in rat tissues. To avoid possible enzymatic de
gradation during sample manipulation, tissue extracts were prepared un
der acidic conditions using trifluoroacetic acid. The tissue contents
of free HCNP and of precursor protein were determined by radioimmuno-a
ssay (RIA) using two antibodies with different specificities, and by a
combination of HPLC and RIA. Free HCNP was detected in neuronal and r
enal tissues, but not in liver. All tissues examined had measurable am
ounts of HCNP precursor protein. The concentrations of free HCNP and p
recursor in neuronal tissues were inversely related to the age. These
results suggest that the deacetylated analogue of HCNP and its precurs
or protein may have significant physiological functions, especially in
the central nervous system of young animals.