[A study of tissue transfer of cefmetazole in the blood and uterus in pregnant rabbits].

Analysis was made to determine concentrations of cefmetazole (CMZ) in maternal serum, and intrauterine tissues of myometrium, placenta, fetal membrane, amniotic fluid and fetal lung after one shot intravenous infusion of 100 mg of CMZ to rabbits with 25th day-pregnancy, and the following results were obtained. 1. Concentrations of CMZ in maternal serum, myometrium and placenta reached their maximum levels in 30 minutes after administration, then decreased rapidly. 2. The concentration of CMZ in the fetal membrane reached its maximum level in 30 to 60 minutes after the administration, then it decreased to a nearly constant level. 3. The concentration of CMZ in the amniotic fluid showed its maximum level in 30 minutes after administration, then decreased, but somewhat increased again thereafter. 4. The concentration of CMZ in the fetal lung was elevated gradually after administration, then decreased after reaching its maximum level at 90 minutes, after administration to a nearly constant level. It was deemed, however, that higher concentrations would be necessary to achieve therapeutic effects because attained concentrations were lower than those in other tissues.