EFFECT OF CYTIDINE DIPHOSPHATE CHOLINE ON ANOXIA TOLERANCE OF CULTURED MYOCARDIAL-CELLS

Three series of cultured Wistar rat heart cells (10 treated and 10 controls X 3) were examined with a laser contraction-meter in a special chamber for anoxia to determine whether cytidine diphosphate choline (CDPC), a membrane phospholipid precursor, can protect against total oxygen deprivation. Heart rate and force of contraction (inotropism) were monitored during a 40-minute period of hypoxia. CDPC in a concentration of 142-mu-g/ml-1 was added to the culture medium only during the anoxia period in series I, during the 3 days of culture in series II, and during the 3 days of culture and the 40-minute hypoxia period in series III. In series I, inotropism decreased by 21% versus 55% in control group (P<0.05). In series II, inotropism decreased by 25% versus 43% in control group (P<0.05). In series III, inotropism decreased by 22% versus 44% in control group (P<0.05). Compared with control cells, cells treated with CDPC during anoxia maintained a significantly greater inotropic state. The effect is greatest if the cells are weak, as in series I. CDPC may be a useful component of the cardioplegic mixture during cardiopulmonary bypass and in the treatment of myocardial ischemia.