Effects of neuropeptide Y (NPY) on isolated guinea‐pig heart

Neuropeptide Y (NPY) is present in nerve fibres throughout the mammalian heart. We have elucidated the effects of NPY on the isolated papillary muscle and heart (Langendorff) from the guinea‐pig. The paced papillary muscle was studied with regard to duration of the action potential, peak force, maximum rate of force development, time to peak force, and time from peak force to half relaxation; all these parameters were identical whether or not...