Histological Effects and Prenatal Exposure to Crude Aqueous Extract of Morinda lucida Leaves on the Frontal Cortex of Growing Wistar Rats

Background: The use of medicinal plants has always been part of human culture and is common in Africa. Amongst the medicinal plants commonly used in Nigeria for management/ treatment of various types of ailments is Morinda lucida Benth.

Aims: This research work was designed to investigate the effects of prenatal exposure of Morinda lucida on the frontal cortex in wistar rats.

Methods and Materials: A total of 25 pregnant wistar rats with an average weight of 150g were randomly divided into five groups (A-E) of five (5) rats each. Group E served as control and were given normal saline. Groups A, B, C and D were orally administered with Morinda lucida (400mg/kg) on the first, second, third and all weeks of pregnancy respectively. The litters in each group were then weighed and sacrificed by cervical dislocation on days 1, 7, 14, 21, 28 and 35 after birth. The brains were also weighed after sacrifice and the frontal cortex excised, fixed in formocalcium for routine histological techniques as well as homogenized in 0.25M sucrose solution, pH 7.4 for quantitative histochemical techniques. The photomicrographs of the frontal cortex of the control and the treated groups were observed and compared for changes and differences.

Results: The findings from this research work showed that for the brain stained with heamatoxylin and eosin the treated groups (A,B,C & D) were not different from the control group(E) in the development of their neurons as there were no alterations in their microarchitecture that is, no vacuolations suggesting cell death were seen and the cells appear well defined and also from the biochemical analysis, there are tissue damage which showed that there are no degradation, there are signs of normal development and there are proliferation and cell maturation.

Conclusion: From this study, it was found that Morinda lucida have no toxic or deleterious effect as it does not alter carbohydrate metabolism, does not cause any loss of Nissl substance and did not affect the microarchitecture of the neurons if administered during pregnancy.