Levels of lactate in lung tissue during sympathetic stimulation

Abstract

The lactate level of blood entering and leaving the lungs during electrical stimulation of its sympathetic innervation was studied in 16 dogs anesthetized with chloralose. The production of lactate by the lungs was determined from the product of the A-V [atrioventricular] blood difference across the lungs and the cardiac output. Blood samples for analysis were taken from catheters placed in the right and left ventricles. Cardiac output was determined from the dye-dilution method. In the control period, the lactate release from the lungs averaged 27.0 mg/min., whereas stimulation for 10 min. caused an increase to an average of 133.9 mg/min. Fifteen to 30 min. after stimulation, formation of lactate decrease to 39.06 mg/min. Levels of lactate in blood-free lung tissue samples were determined before, during, and after sympathetic nervous stimulation. Lactate levels in the control period averaged 3.86 mg/100 g of lung tissue, whereas during stimulation the level rose to 6.57 mg/100 g.