Cardioprotective effect of glutathione in isoproterenol - induced myocardial necrosis in albino rats

The present study was designed to investigate the cardioprotective effect of oral administration of reduced glutathione [GSH] in the isoproterenol [ISO]-induced cardiac lesions in rats; an animal model for myocardial infarction in man. Eighteen adult male albino rats were randomly allocated into 3 groups; each of 6 rats. Rats of control group were subcutaneously injected daily with 2 ml normal saline on days 14 and 15. Rats of ISO group were subcutaneously injected with isoproterenol hydrochloride [Lab. Renaudin, France] with a daily dose of 85 mg/kg body weight [b.wt.] on days 14 and 15. Rats of ISO/GSH group received orally GSH with a daily dose of 500 mg/kg. b.wt. for fifteen days. In addition, animals of ISO/GSH group were injected with ISO with the same regimen as mentioned in ISO group. On day 16, all animals were sacrificed and the hearts were excised and processed for histological and immunocytochemical microscopic examinations. The results of the present study confirmed the ISO-induced myocardial lesions including cardiomyocyte necrosis accompanied by mononuclear inflammatory cells infiltration, interstitial edema as well as mild increase of collagen fibers. Administration of reduced glutathione with and before ISO injections markedly prevented almost all of these changes. These findings proved that oral administration of reduced glutathione exerts a strong cardioprotective effect in ISO-induced cardiac damage in rats

Effect of cyclosporin [A] administration and withdrawal on the mesenteric lymph nodes in albino rats

The present study investigated the histological changes induced in the mesenteric lymph nodes of albino rats by short-term cyclosporin A [CsA] administration and to determine the reversibility of these changes after CsA withdrawal. Eighteen adult male albino rats were randomly allocated into 3 groups; each of 6 rats. Control rats received a daily subcutaneous [s.c.] injection of olive oil at a dose of 1 ml/kg body weight [b.wt.] for 5 days. Control rats were sacrificed either 24 hours or one week after the last injection. Rats from CsA-treated group received a daily s.c. injection of CsA at a dose of 15 mg/kg b.wt. for 5 days. Rats were sacrificed 24 hours after the last injection. Rats from CsA-withdrawal group received a daily s.c. injection of CsA at a dose of 15 mg/kg b.wt. for 5 days. Rats of this group were sacrificed one week later. The results showed that CsA administration induced decreased cellularity of the mesenteric lymph nodes with decrease of CD3 positive T cells, CD57 positive cells and CD20 positive B cells. In contrast, CD68 positive macrophages increased. The germinal centers of lymphoid follicles were enlarged with a thin mantle. Numerous tingible-body macrophages were found in the germinal centers with multiple apoptotic bodies giving the starry-sky appearance of the germinal centers of the follicles. These histological changes showed regression or complete resolution with withdrawal of CsA administration

Inhibition of bleomycin-induced lung damage in mice by curcumin

The present study investigated the protective effect of curcumin administration on the development of lung injury produced by intranasal instillation of a single dose of bleomycin hydrochloride in adult male mice. Twenty four adult male mice were used for the present study. The animals were divided into four groups. All animals were intranasally instilled with either normal saline or bleomycin hydrochloride [0.5 mg for each mouse]. Curcumin was administered by gastric intubation to half of both bleomycin-instilled and normal saline-instilled animals ten [lays before intranasal instillation, and then daily until fifteen days post-instillation. At the end of the study, all animals were sacrificed and the lungs were dissected and processed for histological and immunocytochemnical examinations. The results showed that daily oral administration of curcumin reduced the lung damage induced by bleomycin instillation as evidenced by less inflammatory cells, less deposition of collagen, less thickening of alveolar sepia and less collapse of alveolar spaces. Compared to those receiving bleomycin alone, the results of this study suggested that administration of curcumin was useful in reducing lung damage induced by bleomycin and raised the possibility of efficient treatment of human pulmonary fibrotic disease

Light and electron microscopic study of the effect of experimentally-induced colitis on the adrenal gland of albino rats

This study was performed to investigate adrenal changes in chemically-induced colitis in rats. Twelve adult male albino rats were used for the present study. The animals were allocated into two groups. Animals of control group received a single intracolonic instillation of 0.8 ml of normal saline for each rat while those of colitis group received 0.8 ml of 4% acetic acid for each rat. After seven days, all animals were sacrificed and the adrenal glands were dissected and processed for histological, immunocytochemical and electron microscopic examinations. The results showed light and electron microscopic changes in the adrenal glands of animals with colitis. Many adrenocortical cells showed abnormal large cytoplasmic vacuoles, representing large extracted lipid droplets. Many medullary chromaffin cells revealed obvious cellular damage and marked depletion of secretory granules. These changes could be attributed to the effect of certain inflammatory cytokines on the adrenal gland. The results of this study provide evidence to support the hypothesis that an excessive stress, such as prolonged inflammatory stress, may contribute to the development of obvious lesions in the adrenal gland