Arginine vasopressin release from human platelets after irreversible aggregation.
1. The release of arginine vasopressin from human platelets was investigated in platelet-rich plasma after irreversible aggregation induced by adenosine 5'-pyrophosphate, collagen, sodium arachidonate, thrombin and adrenaline in vitro. 2. Arginine vasopressin levels were significantly higher in the supernatant from stimulated platelet-rich plasma than from unstimulated samples, reaching 3.5 X 10(-12) (range 1.6-12.5 X 10(-12) mol/l in the absence of an aggregating agent, 8.8 X 10(-12) (range 4.2-17.5 X 10(-12) mol/l after adenosine 5'-pyrophosphate, 13.7 X 10(-12) (2.2-63.2 X 10(-12) mol/l after collagen, 7.8 X 10(-12) (2.2-14.6 X 10(-12) mol/l after sodium arachidonate, 7.8 X 10(-12) (2.2-16.3 X 10(-12) mol/l after thrombin and 12.2 X 10(-12) (4.8-32.1 X 10(-12) mol/l after adrenaline. 3. An arginine vasopressin level of 18 X 10(12) mol/l, which can be achieved physiologically, increased the sensitivity of platelets to adenosine 5'-pyrophosphate and collagen in vitro; the same concentration of arginine vasopressin caused a potentiation of the effect of catecholamines on the response of platelets to sodium arachidonate. 4. These results indicate that intraplatelet arginine vasopressin is released during aggregation and suggest that a local release of arginine vasopressin could occur after complete platelet aggregation in vivo.
Anfossi
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G
Clinica Medica Generale III, University of Turin, Ospedale S. Luigi Gonzaga, Orbassano (TO), Italy.
Mularoni
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E
Trovati
M
M
Massucco
P
P
Mattiello
L
L
Emanuelli
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G
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000328:Adult; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000494:pharmacology; D001127:Arginine Vasopressin / Q000097:blood*; D001792:Blood Platelets / Q000378:metabolism*; D003094:Collagen / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D010974:Platelet Aggregation / Q000187:drug effects; D013917:Thrombin / Q000494:pharmacology
D001095:Arachidonic Acids; D001127:Arginine Vasopressin; D016718:Arachidonic Acid; D000244:Adenosine Diphosphate; D003094:Collagen; D013917:Thrombin; D004837:Epinephrine