| Abstrakt: |
A role for serotonin in regulation of uterine blood volume (UBV) was investigated by testing estrogen-induced UBV changes in the presence of cyproheptadine and by measuring uterine serotonin concentration at 0, 65, and 125 min following estradiol administration. Rats, castrated on Day 0, were given maintenance doses of estradiol benzoate on Day 7 and 17β-estradiol, 0.5 μg/kg, iv, at time zero on Day 14. At 125 min doses of cyproheptadine which caused a 70% inhibition of the pressor responses to administered serotonin caused a significant reduction in UBV of estrogen-treated animals. Uterine serotonin content was determined by high-performance liquid chromatography with electrochemical detection. Uteri taken at 65 min after the intravenous estradiol showed no significant change in serotonin content or blood volume. At 125 min when the UBV of estrogen-treated animals was 172% of saline control UBV, uterine serotonin was significantly increased (541 ng/g vs 248 ng/g, P= 0.05). |
