Effect of prolonged consumption of cola drinks on parathyroid gland in rats: light and electron microscopic study

This study aimed to evaluate the effect of consumption of cola drinks on blood calcium and phosphorus levels as well as parathyroid glands [PTG] in rats. Rats were divided into three groups: Group I was a control group, Groups II and III received commercial coca cola by gastric intubation at a dose of 60 ml/day divided into three times for one and two months, respectively. Parathyroid glands were examined by light and electron microscopes. The study revealed decreased serum calcium and increased serum phosphorus levels which led to compensatory hyperplasia of chief cells of PTG of rats that consumed cola for one month. These hyperplastic cells showed evidences of hyperactivity as dilated prominent r ER cisternae, cell membrane folding and increasing secretory and prosecretory granules. On the other hand, after a consumption of cola for two months, serum calcium level was higher than the other group but still lower than the normal value and this was reflected on the PTG of rats of this group which exhibited exhaustive degenerative and apoptotic changes of the hyperplastic hyperfunctioning dark chief cells

Comparative histological study of the effect of static and alternating magnetic fields on the testicular tissue of albino rats

Twenty-five adult male albino rats were used in this study and divided into three groups. Group I [five rats] was used as a control and groups II and III [ten rats each] were exposed to static [direct] and alternating [time varying] EM fields [10 mT, 2 hours/day for 30 days, respectively]. At the end of the experiment, the rats were sacrificed by decapitation and specimens from the testis were taken and processed for light [H and E and trichrome stains] and electron microscopic study. The results indicated that the testis of animals of group II revealed the degeneration of peripheral seminiferous tubules affecting spermatocytes, spermatids and spermatozoa. They showed pyknotic nuclei and vacuolated cytoplasm. Leydig cells were also affected. Interstitial hyalinization and vacuolation were noticed. These changes were confirmed by ultrastructural examination, which revealed various degenerative changes in the nuclei, cytoplasm and organelles of the spermatogenic layers and Leydig cells. Fibrosis was an obvious finding seen by using trichrome stain. In group III, the same changes were observed, but in a more severe and extensive manner. A complete lysis of spermatogenic cells was observed in some tubules, which were lined only by spermatogonia and sertoli cells