Immunohistochemical determination of effects of Withania Somnifera root extract on noise stress induced adenohypophysis in albino rats

ABSTRACT

To access the ameliorating role of Withania somnifera root extract on noise stress effected Adenohypophysis morphology in albino rats by immuno-histochemical method. Experimental and observational study. This study was carried out at Department of Anatomy, Basic Medical Sciences Institute, Jinnah Postgraduate Medical center Karachi from January 2008 to December 2011. 90 adult male albino rats were divided into 3 groups A, B, C each group was divided into 2 subgroups A1-A2, B1-B2 and C1-C2 [24 hrs and 30 days] obtaining15 animals each. Group A served as control, group B were exposed to 100dBA noise for 24 hrs and 6hrs/day for 30 days as experimental design and group C was protected with Withania somnifera root extract along with noise stress. The animals were sacrificed at the end of experimental period of each subgroup and blood samples were collected for hormonal assay of the plasma ACTH and plasma Corticosterone concentration. Pituitary gland was removed from each animal and prepared for microscopic examination by immunohistochemical method. Immunohistochemical study reveals that, the black brown pigments deposited more in group B2 animals and reduced in group C animals Adenohypophysis indicated by ACTH monoclonal antibody Clone-56. The ACTH level was highly significantly increased after 24hrs and 30 days. The Corticosterone level was highly significantly decreased after 24hrs and not as much decreased after 30 days. It was restored insignificantly in protected groups after 24hrs and 30 days. Withania somnifera root extract has preventive efficacy against noise stress, immunohistochemistry confirmed that, less extent of black brown pigment deposition was the amount of corticotropes