Transcript No Slide Title

NPY Inhibition of Catecholamine Release
SIGMA-ALDRICH
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).