Release of immunoreactive-neuropeptide by rat platelets.
Neuropeptide Y, a potent vasoconstrictor and cardiac depressant, is re-leased from sympathetic nerve endings. Its presence in megakaryocytes suggests this peptide might be stored in platelet granules and released during aggregation. Immunoreactive-neuropeptide Y was measured in platelet rich and platelet poor plasma, and was substantially greater in the former. Addition of collagen to platelets resulted in release of neuropeptide Y which paralleled, in a concentration-dependent manner, the degree of platelet aggregation. Adenosine diphosphate, at concentrations which induce only the first phase of aggregation and not the release reaction, caused only a minor release of neuropeptide Y. These results suggest that platelet release could be a major source of circulating neuropeptide Y and could contribute to hemodynamics of pathophysiological states involving platelet activation.
Department of Physiology and Biophysics, Georgetown University Medical Center, Washington, DC 20007.
A K
AK
Myers
M Y
MY
Farhat
C A
CA
Vaz
H R
HR
Keiser
Z
Z
Zukowska-Grojec
D000244:Adenosine Diphosphate; D000818:Animals; D001792:Blood Platelets / Q000378:metabolism* / Q000502:physiology; D003094:Collagen; D008297:Male; D009478:Neuropeptide Y / Q000097:blood / Q000378:metabolism* / Q000502:physiology; D010974:Platelet Aggregation; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors
D009478:Neuropeptide Y; D000244:Adenosine Diphosphate; D003094:Collagen