VINIKKA, LASSE, JUHANI VUORI, and OLAVI YLIKORKALA. Lipid peroxides, prostacyclin, and thromboxane A2 in runners during acute exercise. Med. Sci. Sports Exerc., Vol. 16, No. 3, pp. 275-277, 1984. We studied the effect of physical activity on lipid peroxidation and on the production of antiaggregatory, vasodilatory prostacyclin (epoprostenol, PGI2) and its endogenous antagonist, thromboxane A2 (TxA2) in 10 well-trained long-distance runners before, during, and after maximal exercise on a cycle ergometer. Pre-exercise levels of lipid peroxides (2.0 +/- 0.4 [mu]mol[middle dot]l-1, [Latin capital letter X with macron above] [middle dot] SD), plasma immunoreactive 6-keto-prostaglandin F1a (i 6-keto-PGF1a, a metabolite of PGI2) (192.8 [middle dot] 51.7 pmol[middle dot]1), and serum immunoreactive thromboxane B2 (i TxB2, a metabolite of TxA2) (703.3 [middle dot] 290.1 nmol[middle dot]1) did not differ from those of 10 non-athletic controls. Plasma i 6-keto-PGF1a was increased at the seventh minute of the exercise test, but not any more at the end of the exercise or 30 min later. Lipid peroxides or i TxB2 did not change. Our data suggest that the changes of the PGI2/TxA2-ratio induced by long-term or acute physical exercise are too small to explain the protective effect of physical fitness against coronary heart disease.
(C)1984The American College of Sports Medicine