Effects of pseudolaric acid B on blood flows of endometrium and myometrium in pregnant rats

Effects of pseudolaric acid B (PB) on endo- and myo-metrial blood flows were measured by hydrogen gas clearance technique in 336 pentobarbital-anesthetized rats divided into control and 2 medicated groups (ig PB 20 and 30 mg.kg-1 on d 7-9 of pregnancy). Measurements of endo- and myo-metrial blood flows were done on d 7-14 of pregnancy. Results showed that the endo- and myo-metrial blood flows were reduced by 33-66% and 30-65% respectively, vs ig 1% CMC 0.5 ml (P less than 0.01). Uterine weight during d 10-14 of pregnancy stopped gain. The systemic arterial pressure remained relatively unchanged. It is concluded that PB causes a significant decrease of blood flow in both endo- and myometrium, which is accounted as the most important cause of embryo's death.