© 1989 Oxford University Press
research-article |
Prenatal Reserpine Exposure Alters Cardiovascular Parameters in Rat Offspring
*Perinatal and Postnatal Evaluation Branch, Division of Reproductive and Developmental Toxicology, National Center for Toxicological Research Jefferson, Arkansas 72079
Reproductive and Developmental Toxicology Branch/OHEA, U.S Environmental Protection Agency Washington, DC. 20460
Received September 19, 1988; accepted May 25, 1989
Electrocardiograms (ECGs) and blood pressures (BPs) were recorded and evaluated in postnatal rats that had been exposed in utero to 0.375 or 0.75 mg reserpine/kg/day sc on Gestational Days (GD) 12–15. These doses caused reduced maternal weight gain during pregnancy and decreased pup body weight at birth, as well as reduced heart weight during the preweaning period. There were no changes in other maternal parameters or in litter size. During the postweaning period, pup body weight was reduced only at the highest dose at Postnatal Days (PND) 30 and 60. By PND 342, the weight reduction was no longer significant when compared to controls. Lead II ECGs were recorded in conscious animals on PND 30, 60, and 342; BPs were recorded in anesthetized animals on PND 346. Several ECG parameters were attenuated by prenatal reserpine exposure: R wave and S wave amplitudes and the QRS interval in males, and the PR interval in females. The BP recordings showed that low-dose males had significantly higher pulse pressures than did high-dose males, but neither group was significantly different from controls. Following an intraarterial norepinephrine challenge, resultant peak pulse pressure was greater in high-dose females than in controls. These results indicate that subtle, long-term, sex-specific alterations in cardiovascular parameters were produced by prenatal reserpine treatment at doses that altered body weight in young animals at PNDs 30 and 60, but this change was no longer apparent at PND 342.