Co-release of neuropeptide Y and catecholamines during physical exercise in man

Venous plasma levels of neuropeptide Y-like immunoreactivity (with chromatographic properties of synthetic neuropeptide Y) increased in parallel with catecholamines, heart rate and blood pressure during graded physical exercise in man. The plasma levels of neuropeptide Y correlated better with the levels of noradrenaline than adrenaline, suggesting release of a neural origin. Taken together with previous results, this suggests that neuropeptide Y is released together with noradrenaline upon sympathetic activation during physiological conditions in man. Determinations of plasma neuropeptide Y may therefore be valuable in the assessment of sympathetic nerve activity.