Forearm blood flow responses to neuropeptide Y, noradrenaline and adenosine 5'-triphosphate in hypertensive and normotensive subjects

• Neuropeptide Y (NPY), noradrenaline (NA) and adenosine 5'-triphosphate (ATP) are important co-transmitters in the sympathetic nervous system, which has a central role in cardiovascular control. In order to evaluate if hypertension is associated with alterations in vascular responses to sympathetic co-transmitters we studied the effects of intra-arterial infusion of NPY, NA and ATP on forearm blood flow. Blood flow was measured by venous occlusion plethysmography in six hypertensive (mean arterial blood pressure (MAP) 113 +/- 4 mmHg) and six matched normotensive subjects (MAP 97 +/- 3 mmHg). NPY and NA significantly reduced forearm blood flow, while a powerful increase was seen with ATP. Forearm vascular resistance, calculated as MAP divided by forearm blood flow, was significantly increased by NPY and NA and strongly reduced by ATP. There was no difference between hypertensive and normotensive subjects in response to either transmitter. In conclusion, vascular reactivity to intra-arterial administration of NPY, NA and ATP seems to be intact in hypertensive patients without metabolic aberrations.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Kardiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Cardiac and Cardiovascular Systems (hsv//eng)

Keyword

forearm blood flow

adenosine 5'-triphosphate

hypertension

neuropeptide Y

noradrenaline

Publication and Content Type

art (subject category)

ref (subject category)