Influence of beta-receptor stimulation on catecholamine and phospholipid concentrations in lungs of fetal rabbits

It was studied whether the beta-receptor stimulating fenoterol had any influence on endogenous catecholamines in the lung tissue of fetuses. On the 23rd, 27th and 31st days of pregnancy, concentrations of noradrenaline and dopamine in the lung homogenate of mature and immature rabbit fetuses were determined by fluorometry, and the basic surfactant components total phospholipids and lecithin by colorimetry, in a group receiving beta-mimetic treatment and in a control group receiving physiological salt solution. The concentration of noradrenaline decreased with the progression of pregnancy but the concentration of dopamine did not change significantly. Application of fenoterol caused an increase in total phospholipids and lecithin in the lungs of 23 and 27 day old rabbit fetuses and decreased the concentration of catecholamines, especially of noradrenaline. The drug had no such effect in mature (31 day) fetuses.