Effects of Meluadrine Tartrate on Maternal Metabolic Responses and Fetal Hemodynamics in Pregnant Goats

This study was designed to elucidate the effects of meluadrine tartrate on maternal metabolic responses and fetal hemodynamics in unanesthetized, chronically instrumented pregnant goats. After the administration of meluadrine tartrate to pregnant goats or directly to fetuses, changes in heart rate (HR), arterial blood pressure and arterial blood pH, gasses, electrolytes and metabolic responses were measured. The constant administration of meluadrine tartrate (0.1 microg. kg(-)(1). min(-)(1)) to pregnant goats resulted in the increases of maternal HR, glucose and free fatty acid and the decrease of maternal blood K(+) concentration. The direct escalating administration of meluadrine tartrate (0.01, 0.03 and 0.1 microg. kg(-)(1). min(-)(1)) did not increase the fetal HR, while ritodrine hydrochloride (0.3, 1 and 3 microg. kg(-)(1). min(-)(1)) to fetuses increased the fetal HR dose-dependently. The present study suggests that meluadrine tartrate has a mild influence relative to the effects of ritodrine to the maternal metabolic responses and fetal cardiovascular function.