Determination of the ratio of the contractions, induced by thromboxane A2 in the guinea pig lung parenchymal strip after exogenous administration and formation in the tissue.
A comparison was made of the contractile effects of exogenously added and endogenously formed TxA2 on guinea pig lung parenchyma. Aggregating platelets were used as a source of exogenous TxA2. After the addition to the lung strip, the contractions were measured. Endogenous formation of TxA2 was induced by adding either 1 micrograms P1A2 or 50 ng LTD4 to the strip. It was found that the ratio of potency of action of endogenous/exogenous TxA2 was 5.1 +/- 0.62 for P1A2 and 5.0 +/- 1.3 for LTD4.
D000818:Animals; D001792:Blood Platelets / Q000502:physiology; D006168:Guinea Pigs; D008168:Lung / Q000187:drug effects / Q000502:physiology*; D009119:Muscle Contraction / Q000187:drug effects*; D051381:Rats; D013928:Thromboxane A2 / Q000096:biosynthesis / Q000097:blood / Q000494:pharmacology*; D013931:Thromboxanes / Q000494:pharmacology*
D013931:Thromboxanes; D013928:Thromboxane A2