Estradiol induced thymus alterations in adult male albina rat: histological and immunohistochemical study

Thymus is responsible for generation of most of circulating T-cells, Although estrogen regulates thymic development, exposure to increasing amounts of exogenous estrogen would modulate thymus structure, function as well as immune system. Was to study the structural changes of thymus after estradiol injection in an attempt to verify the mode of action. 40 adult male albino rats were used dividing into control and experimental groups. Each animal of experimental groups [B 1, B2 and B3] was injected subcutaneously with 5, 25 and 50 mg/kg body weight of estradiol valerate [E2], respectively daily for two weeks. Thymus was dissected and weighted. One lobe was processed for paraffin sections and stained with TUNNEL method to demonstrate apoptosis and the other one used to be examined by transmission electron microscope. Thymus was shrunk and its weight was significantly decreased only in subgroups B2 and B3. Their LM examinations showed degenerated thymocytes and epithelial cells with dense bodies and debris in between intact cells. Large cells enclosed disrupted cells within their cytoplasm. EM examination revealed degenerated thymocytes exhibiting criteria of apoptosis, apoptotic bodies, degenerated epithelial cells and vacuoles of different sizes and shapes inside or outside the cells. Large cells exhibited criteria of epithelial cells enclosed within their cytoplasm intact cells, apoptotic cells, apoptotic bodies and lysosomes were observed. Macrophages with lysosomes and tissue debris were also recorded. Immunohistochemical studies revealed marked increase in the dense brown apoptotic nuclei in subgroups B2 and B3 comparing with control. Estradiol induced involution and degeneration of thymus through increasing apoptosis of thymocytes

Histological study of the effect of simvastatin on the skeletal muscle fibers in albino rat and the possible protective effect of coenzyme Q 10

Simvastatin is a lipid lowering agent. It reduces risk of mortality in persons with coronary heart disease. Some patients treated with simvastatin, have developed liver, kidney and skeletal muscle symptoms. Coenzyme Ql0 has a significant antioxidant activity acting as a primary scavenger of free radicals and influences membrane stability in many tissues including skeletal muscle. Was to evaluate the effect of simvastatin drug on the histological structure of skeletal muscle fibers of adult male albino rats and the possible role of coenzyme Q10 [C0Q 10] as a protective agent. 38 adult male albino rats were used and divided into three groups. Group I [control], group II included 10 rats treated with simvastatin for 4 and 12 weeks and group III included 10 rats treated with simvastatin and CoQ 10 orally for 4 and 12 weeks. The gastrocnemius muscle was dissected and prepared for light and electron microscopic study. In rats subjected to high therapeutic dose of simvastatin for 4 and 12 weeks, the gastrocnemius muscle showed variation in size, splitting and focal degeneration of myofibers as well as mononuclear cellular infiltration and increased deposition of collagen fibers in-between muscle fibers. EM revealed mitochondrial degeneration and dilatation of sarcoplasmic reticulum. Mitochondria were markedly accumulated between myofibrils and in subsarcolemmal space. Coadministration of coenzyme Q 10 with simvastatin for 4 and 12 weeks ameliorated most of the above mentioned histological changes in the animals used. Simvastatin drug caused skeletal muscle damage. Coenzyme Q 10 resulted in protection of the skeletal muscle fibers when given concomitantly with simvastatin

possible protective effect of corticosteroids on bleomycin induced pulmonary toxicity light and electron microscopic study

Bleomycin is an antitumor antibiotic having a high significant activity and wide use in the clinical field. The most serious adverse reaction to bleornycin therapy is the life-threatening pulmonary toxicity and fibrosis. Was to study the effect of bleomycin injection with and without corticosteroid on the lung of adult male albino rat using light and electron microscopy. 30 adult male albino rats were used dividing into two main groups; group A [control group], group B [experimental group] included 20 rats, ten rats each injected i.p with 0.5 mg of bleomycin sulphate twice weekly for four weeks and ten rats each injected i.p with 0.5 mg of bleomycin sulphate twice weekly for 4 weeks in concomitant with daily i.m. injection of 0.4 mg of prednisolone for the same period. Bleomycin treatment induced variable degrees of lung injury disrupting the normal architecture. Overexpansion of alveoli alternating with collapse of others, congestion of blood vessels, cellular infiltration and fibrosis were all observed. Ultrastructurally, pneumocyte II showing disrupted mitochondria and destruction of lamellar bodies. Pneurnocytes type II were predominant replacing the disappeared pneumocyte type I in the alveolar lining. Activation of alveolar macrophages and deposition of collagen fibres in the interstitial tissue were all noticed. Concomitant use of bleomycin with pridnisolone revealed the same histological changes. Only the pneumocyte type II proliferation was less and increase in collagen fibers deposition was not observed comparing with control. Corticosteroids inhibited or at least delayed pulmonary fibrosis induced by bleomycin treatment

Histological study of the effect of amiodarone on thyroid follicular cells in albino rat and its management using carbimazole with and without prednisolone

Amiodarone is increasingly used in a number of cardiac conditions but it has a significant side effect profile, which includes thyroid dysfunction. Was to study the toxic effect of amiodarone on thyroid gland and its management using carbimazole with and without prednisolone. 40 adult male albino rats were used and were divided into four groups, group A [control group], group B each animal was treated daily with 2.7 mg of amiodarone for three months, group C: Each animal was treated daily with 2.7 mg of amiodarone for three months then was given I rug of carbimazole in concomitant with amoidarone for another one month and group D: Each animal was treated daily with 2.7 mg of amiodarone for three months then was given 1 mg of carbimazole and 0.4 mg prednisolone in concomitant with amoidarone for another one month. At the appropriate times, thyroid glands were dissected and prepared for both light and electron microscopic studies. LM study of thyroid gland treated with amiodarone exhibited changes ranged from normal pictures to irregular thyroid follicles with disrupted lining epithelium and marked cellular infiltration in-between. EM study showed irregular nuclei with chromatin condensation, dilatation of RER, increased lysosomes and inclusion bodies and vesiculation of cytoplasm. Addition of carbimazole reflected partial improvement while addition of both carbimazole and prednisolone exhibited marked improvement nearly of all the thyroid specimens. Amiodarone therapy induced thyroid toxicity which could be managed by addition of carbamazole and prednisolone to amiodarone

Effect of irradiation on secretory cells of submandibular gland of adult male albino rat. histological and immunohistochemical study

The submandibular glands are commonly included in the radiotherapy field for the treatment of head and neck malignancies. Many clinical problems are produced but their mechanisms are still not understood. Was to study the effect of irradiation on secretory cells and aquaporin 5 [AQP5] distribution in submandibular gland as a trial to understand the mechanism of gland dysfunction. 15 adult male albino rats were used and were divided into two groups, group A [control group] contained five rats and group B [irradiated group] contained ten rats. Each rat in group B was irradiated with single dose of 15Gy delivered by the X-ray unit. One week after irradiation submandibular glands were dissected and were processed for histological and immunohistochemical [aquaporin 5] examination. LM study exhibited that irradiation led to cytoplasmnie vacuolization especially in serous acini with widening of spaces in-between the acini in the submandibular glands. EM study showed irregular nuclei with chromatin condensation, dilatation of RER and cytoplasmic vacuolizat ion, As regards the secretory granules, serous acini showed degranulation while the granules of mucous acini exhibited amorphous-like electron dense materials. Aquaporin 5 [AQP5] in the control group was localized in apical membrane of serous acini while absent in mucous one. After irradiation the serous acini of submandibular glands exhibited marked decrease in AQP5. Irradiation induced morphological disruption in secretory cells of submandibular gland and marked decrease in AQPS, both would responsible for gland dysfunction

Effect of experimentally induced ischemic-reperfusion on the testis and the possible protective role of L-carnitine in the adult albino rat; histological, histochemical and immunohistochemical study

Ischemic-reperfusion [I/R] injury is a possible cause of testicular damage and infertility after testicular torsion. L-carnitine is a naturally occurring compound widely distributed in all cells and plays a pivotal role in spermatogenesis. Was to study the effect of I/R injury on the structure of testis on the same side with or without L-carnitine. 25 adult albino rats were divided into group I [control], group II [left spermatic cord was clamped for 60 min [I/R]] and group III [each animal received 500 mg/kg L-carnitine i.p. 30 min before reperfusion]. All animals were scarified after 4 weeks and the testes were processed for histological, histochemical and immunohistochemical studies for Bcl-X and testosterone Ab-1. Furthermore, statistical analysis for percentage of sperms abnormalities was examined in smears from the head of the epididymis. I/R injury induced severe affection of the spermatogenic cells and changes in the Leydig cells activity. The changes were improved in animals that received L-carnitine [Group III]. The spermatogenic and interstitial cells in this group appeared more or less as these of the control. The Bcl-X protein was apparently increased in I/R group and reduced in group III while the testosterone Ab-1 was increased in some cells of groups II and preserved in group III. I/R resulted in a significant increase in the frequencies of abnormal sperm while L-carnitine improved this lesion. L-carnitine pretreatment appeared to have a protective effect in experimental testicular I/R model in rats by its antioxidant and antiapoptic properties

Light and electron microscopic study on the effect of valproic acid on cerebellar cortex of adult male albino rats and the possible protective effect of L-carnitine

Valproic Acid [VPA] is one of the most widely prescribed antiepileptic drugs and is regarded as a first choice for most forms of seizures. Although valproic acid has a wide therapeutic window, yet it is associated with many adverse effects. L-carnitine is a naturally occurring compound widely distributed in all animal cells. It has neurotropic, neuroprotective and antioxidant properties. The aim of the present study was to evaluate the possible neurotoxic effect of valproic acid [Depakene] on the cerebellar cortex of adult male albino rats when used alone and when given concomitantly with L-carnitine. In this study twenty four adult male albino rats were used and divided into four groups [six rats each]: Group I was the control group, group II [L-carnitine group]: Each animal received 100mg/kg L-carnitine, group III [Valproic acid treated group]: Each animal received 50 mg/kg valproic acid and group IV received valproic acid concomitantly with L-Carnitine. Both drugs were given orally once daily for three months. Light microscopic examination of cerebellar cortex of valproic acid treated animals revealed its prominent neurotoxic effect on Purkinje cells and granule nerve cells in association with vacuolation in the molecular layer. Ultrastructural study of the cerebellum of the same group showed dilated Golgi complex and accumulation of secondary lysosomes in association with nuclear shrinkage and irregularity within Purkinje cell perikarya. Many myelinated nerve fibers and nerve cell processes in the molecular and granular layer belonging to the affected nerve cells displayed similar degenerative changes. On the other hand group IV revealed resolving of most of these alterations. However, few Purkinje and granule nerve cells were seen affected in between the normal ones. It could be concluded according to this research that valproic acid has a prominent neurotoxic effect on the cerebellar cortex of the adult male albino rats that can be reduced by concomitant administration of L- carnitine

Electron microscopic study of the nephrotoxic effect of cyclosporine A and cyclosporine A - in fedipine combined therapy in the rat

Cyclosporine A is a potent immunosuppressive agent used in kidney, liver, heart and other organs transplantation for the prevention of allograft rejection as well as in the treatment of a number of autoimmune diseases. By means of its selective action on the immune system it not only significantly improves the post operative survival rate but also the quality of the life of the transplant patient. However, Cyclosporine A therapy can give rise to a number of side effects including nephrotoxicity and hypertension. Hypertension in Cyclosporine A treated patients is often treated with calcium channel blockers. The one most frequently used in combination with Cyclosporine A is nifedipine. The aim of this work was to evaluate the effect of Cyclosporine A on renal tissue when used alone or in combination with nifedipine. Three groups of animals were used. The first one was used as control; the second one was treated with Cyclosporine A and the third one with Cyclosporine A and nifedipine. The kidney samples were prepared for electron microscopic examination. The kidneys of animals treated with Cyclosporine A alone showed marked degenerative changes affecting both the glomeruli and proximal tubules while those treated with Cyclosporine A and nifedipine showed mild degenerative changes affecting only some of the proximal tubules. So it is recommended to use it with other medications which could reduce its toxic effect

Ultrastructural study of the damaging effect of methotrexate on the rat testis

Methotrexate is one of the widely used cytotoxic agents. Its toxic effects are frequently considered a minor risk when weighed against the potential benefits of the treatment. Testicular and ovarian damage often lead to the loss of the reproductive activity, and have been cited as one of its undesirable risks. So, the aim of the present work was to study further the effect of methotrexate on rat testis. The used experimental animals were divided into 3 groups injected with distilled H[2O] [control group], low doses of the drug and high doses respectively. Light and electron microscopic examination of testes obtained from rat received low doses of the drug showed mild degenerative changes which involved only some spermatocytes and spermatids, while the spematogonia were more or less intact. Those received high doses showed moderate degenerative changes affected most of the spermatogenic cells. Interstitial fibrosis was also seen with the concomitant distortion of the tubular architecture. Therefore, the impairment of reproductive power in males receiving methotrexate can be attributed to the degenerative changes in spermatogenic cells. So, careful use of this drug especially in young men is recommended