NPY Inhibition of Catecholamine Release

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NPY Inhibition of Catecholamine Release
SIGMA-ALDRICH
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NPY Inhibition of Catecholamine
Release Catecholamine synthesis and release are
two separate but related processes that influence
the level of catecholaminergic neurotransmission.
Neuropeptide Y (NPY) is a 36 amino acid peptide
that is highly homologous to peptide YY (PYY).
NPY exerts its various biological effects through
at least six classes of receptors, designated Y1,
Y2, Y3, Y4, Y5, and Y6. It has been demonstrated
that NPY inhibits catecholamine synthesis via the
Y3 receptor subtype, in contrast to the Y2
subtype that mediates inhibition of catecholamine
release. Although inhibition of both synthesis
and release by these receptor subtypes is via
inhibition of Ca2 entry, the two processes are
associated with actions on distinct Ca2 channel
subtypes. Inhibition of L-type Ca2 channels
mediates inhibition of catecholamine synthesis,
while inhibition of N-type Ca2 channels inhibits
catecholamine release. References McCullough,
L.A., et al., Neuropeptide Y receptors involved
in calcium channel regulation in PC12 cells.
Regul. Pept., 75-76, 101-107 (1998). Cavadas,
C., et al., NPY regulates catecholamine secretion
from human adrenal chromaffin cells. J. Clin.
Endocrinol Metab., 86, 5956-5963 (2001).