The effects of neuropeptide Y (NPY) were studied on an in vitro preparation of rabbit iris dilator muscle. NPY by itself (10-11 M to 10-6 M) had no effect on the resting tension or on the maximal electrically-induced response (MER) of the dilator. Phenylphrine (10-9 M to 10-4 M) caused a dose-dependent contraction of the dilator muscle (7.8% to 40.6% of the MER). The addition of NPY 10-6 M enhanced the phenylephrine-induced muscle contraction (8.8% to 76.8% of the MER) without altering the EC50 value (5x10-6 M) of the phenylephrine dose-response curve. These findings support a modulatory role for NPY on the iris dilator muscle.
|Original language||English (US)|
|Number of pages||3|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Jan 1 1988|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience