Smoke and ethanolic extract of nicotiana tabacum altered hippocampal histology and behaviour in mice

The effects of tobacco use on human health are well known and are documented in scientific reports.\udWhen tobacco is smoked or chewed, nicotine is absorbed by the lungs and oral cavity and quickly\udmoved into the bloodstream where it is distributed rapidly through the circulatory system to reach the\udbrain and peripheral nervous system. Male and female adult mice (N=32) were used for this study. The\udanimals were randomly divided in to four (4) groups, A, B, C and D, of eight (n=8) animals each. Group A\udanimals were treated by oral administration of 10.72 mg of the extract, B 10.72 mg of the tobacco smoke\udexposure for 3 min (in a controlled air chamber), C were given 0.2 ml of normal saline and D were\udexpose to equal weight (0.02 g) of cotton wool for 3 min, for 21 experimental days. The mice were\udsacrificed 4 h after the last administration and the brains excised, blotted, weighed and fixed in formol\udcalcium for histological analysis, using Haematoxylin and Eosin. There was a significant decrease in the\udbody weight, brain weight and relative brain weight in the treatment groups. The pyramidal and granular\udcell layers showed changes in cell count scores; significant at p<0.05 when compared with the control.\udThe results suggested that the consumption of Nicotiana tabacum leaves; either smoking or chewing\udmay lead to alterations in cell count, brain weight and neurobehavioral patterns. Weight loss was also\udobserved in the treatment and was found to be dependent on the route of administration