Angiotensin II effects on platelet function.

Y A Ding; D E MacIntyre; C J Kenyon; P F Semple

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PubMed · 2856711

Angiotensin II effects on platelet function.

Y A Ding·D E MacIntyre·C J Kenyon·P F Semple

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Abstract

The effects of angiotensin II (ANG II) alone and in combination with other agonists on platelet aggregation, thromboxane B2 (TxB2) synthesis and cytosolic [Ca2+]i were investigated. Angiotensin II (10(-11)-10(-7) mol/l) alone had no direct effect on aggregation, TxB2 production or [Ca2+]i after short- (< 2 min) or long-term (30 min) incubation. In contrast, low concentrations of ANG II (10(-11) mol/l) enhanced adrenaline-induced platelet aggregation but high concentrations (10(-7) mol/l) had an inhibitory effect. Moreover, ANG II (10(-11)-10(-7) mol/l) augmented platelet responses to the TxA2 mimetic U44069. The facilitatory effect of ANG II on adrenaline-induced platelet aggregation was abolished by pretreatment of platelets with flurbiprofen. Thromboxane B2 synthesis by adrenaline-treated platelets was inhibited by ANG II. The results indicate that ANG II stimulation of agonist-induced platelet activation is due to potentiation of the effects rather than the synthesis of TxA2.

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Angiotensin II Blood Platelets Calcium Humans In Vitro Techniques Platelet Activation Platelet Aggregation Platelet Function Tests Thromboxane B2 Journal Article

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Y A Ding, D E MacIntyre, C J Kenyon, P F Semple. 1985. Angiotensin II effects on platelet function.. https://pubmed.ncbi.nlm.nih.gov/2856711/

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