Morphological Effects of Gonadotrophic Inhibition by Hormonal Contraceptives on the Ovary and its Oogenesis Processes of the Ratus norvegicus

Abstract

The experimental set-up consisted of 3 rats for the control, 3 for the normal treatment and 3 for the overdose treatment group. The treatment group were fed orally with the drug Lo-gentrol from the beginning of their estrus cycle. The test animals were sacrificed on the fourth day (diestrus) and their ovaries isolated for external analysis and histological sectioning. Preliminary external analysis of the ovary of the treated group has shown it to be heavily impregnated with adipose tissues. Threated ovaries appear to have decreased in size and a reduction in its pinkish color was evident. Observations by a dissecting microscope show minimal bulges in the ovarian surface which could be sites of future ruptures. Morphological analysis of serial sections of the treated group showed it to have distinct degenerating follicles. Characterized by a marked thinning of the theca, with boundaries separating the theca externa and interna appearing indistinguishable. Follicle cells making up the stratum granulosum were high disorganized, most cells appeared to have plasmolyzed resulting in no individual cellular boundaries in the granulosa. Increase in the size of the liquor folliculi-filled antrum was also noted in ratio with the stratum granulosum. Area of developing ova was distinguishable but most appear without nucleus and with a vacuolated cytoplasm. Graafian follicles were few and appeared degenerated. The corpus luteum of treated ovaries were present in numbers, but appeared less solid and highly vacuolated. Lutein cells appear smaller, polyhedral shaped and fairly nucleated. Follicles, corpus luteum and ovarian stroma all appeared to be highly vacuolated.

With regards to normal and overdose treatment groups, no marked differences were noticeable, both groups had mostly similar structural reactions to the drug used.