The action of two related peptides, neuropeptide Y (NPY) and peptide YY (PYY) on the mouse vas deferens was investigated. Both peptides potently inhibited in a dose dependent manner, muscle contractions evoked by electrical field stimulation of the intramural neurons but did not alter noradrenaline evoked contractions. They were also found to inhibit the potentiation of the twitch elicited by neurotensin and substance P. NPY and PYY were equipotent in the bioassay. This data suggests the possibility that NPY acts as a neuromodulator of noradrenaline release at a presynaptic level in the mouse vas deferens.
ASJC Scopus subject areas
- Endocrine and Autonomic Systems
- Cellular and Molecular Neuroscience