Reproductive toxicity of marihuana smoke a three-generation study in female wistar rats

A three-generation study on the effects of marihuana smoke on female wistar rats was carried out. The mother/parent generation (Gm) and Gf(first generation) were each bred once to give rise to Gf and Gs(second generation) respectively. Reproductive indices studied included oestrous activity, fertility index,gestation of dams, gestation index, gestation survival index, number of pups born alive and pup birth weight. Reproductive toxicity was observed in this study as evidenced from the delayed onset of oestrous activity, frequently occurring oestrous cycles with shortened period of oestrous, reduced fertility index, premature parturition, diminished pup birth weight, reduced litter size as well as gestation survival index. This work shows that when marihuana is inhaled, neither oestrous activity nor ovarian activity is totally suppressed, but it is affected to a significant degree. Influence of marihuana smoke on excitability of uterine smooth muscle, transfer/utilization of nutrients and on hypothalamo-hypophyseal-ovarian axis was proposed to explain its reproductive toxicity. This study bears clinical implications and is useful in the counselling of female marihuana smokers (AU)

Contractile response of uterine smooth muscle to acetylcholine and marijuana extract

Marijuana extract (ME) is known to influence smooth muscle activity. This study was designed to investigate the effect of crude ME on rat uterine muscle and to explain the mechanism of action using antagonists such as atropine, ergometrine and propranolol. The contractions and the electrical activity were recorded on isolated superfused rat uteri. It is speculated that ME by its uterine stimulation action compromise uterine blood and may affect oxygen/nutrient transfer. The implication of this to the fetus is discussed. (AU)