[Transplacental transfer, tissue localization and morphological study of the rabbit placenta after the administration of pentacaine].

On day 29 of gravidity, the New Zealand white breed rabbits were intravenously administered 3H-pentacaine (0.5 mg.kg-1), a new local anaesthetic agent with anti-ulcerous effect in order to study the distribution in pregnant females. Transplacental passage and a relatively homogenous distribution of unchanged pentacaine were found in the organs of females with the largest accumulation in the lungs. Pentacaine is distributed in the same manner in the fetal organs as in the organs of the mother, but the levels in the foetuses were significantly lower. A morphological study of the rabbit placenta on day 29 of gravidity after the doses of 1, 10 and 50 mg.kg-1 of pentacaine did not show any pathological changes.