Vasoactive effects of nicotine in human umbilical arteries.

The aim of the study was to evaluate the possible influence of cigarette smoking during pregnancy on nicotine dependent umbilical artery contraction in "in vitro" performed experimental study. The vasoconstrictive effect of nicotine was established. The study on umbilical cord artery segments from 23 nonsmokers, 6 light smokers and 8 heavy smokers failed to find the relationship between the doses of nicotine and duration and relative pressure increase of artery contractions. The arteries of heavy smokers showed the statistically significant (P less than .05) lower contraction potency in comparison with nonsmokers in the nicotine concentration of 5*10(-7) M/l. Nicotine alters the umbilical cord artery pressure "in vitro", thus when transferring to "in utero" conditions, might be one of the potent factors adversely affecting perinatal outcome.