Ameliorative effect of vitamin C against hepatotoxicity induced by emamectin benzoate in rats.

In the present study, we aimed to assess the potential protective effect of ascorbic acid (AA) against emamectin benzoate (EMB)-induced hepatotoxicity. For this purpose, biochemical, histopathological and analytical investigations were performed. Male Wistar rats were distributed into three groups, that is, a control group, an EMB group given 10 mg EMB/kg body weight (BW) by gavage and an EMB + AA group given 10 mg EMB/kg BW and vitamin C intraperitoneally (200 mg/kg). The duration of the treatment was 28 days and the duration of the study was 42 days. There was a statistically significant increase of all hepatic biomarkers, that is, aspartate aminotransferase, alanine aminotransferase and gamma-glutamyltransferase activities, and glycemia, in EMB-treated group when compared with the control group. Light microscopic observations revealed variable signs of hepatotoxicity in the EMB group, which were represented by alteration of normal hepatic architecture, inflammatory cell infiltration, hepatocellular steatosis and foci of necrosis at 28 and 42 days post-treatment. However, co-treatment with vitamin C reduced EMB-related liver toxicity and diminished the abnormal biochemical and architectural damage. Emamectin B1a and B1b residues were detectable in all plasma samples of treated rats at 14, 21 and 28 days of treatment. The drug liver tissue concentration was significantly lower in EMB + AA group compared with EMB group at 28 and 42 days. In conclusion, the findings of the present study clearly indicate a significant protective action of vitamin C against EMB hepatotoxicity.

Seasonal plasticity of the pituitary pars intermedia of the one-humped camel (Camelus dromedarius).

The pituitary pars intermedia of Camelus dromedarius is well developed and completely surrounds the pars nervosa. Two major groups of cells are present: endocrine (ec) and glial-like cells (glc). The ec group is composed of three morphologically distinct cell types. Type I, or polyhedral light cells (LC-I) and type II, or polyhedral dark cells (DC-II), have secretory granules of heterogeneous electron density whose size ranges from 170 to 300nm. Type III cells are elongated with homogeneous electron-dense secretory granules of 80-200nm. The glc make up an organized network, form follicles in the centrolobular zones and are positive for vimentin and S-100ß immunolabelling. The nerve fibres penetrating the lobe are numerous, and can be classified into two types according to the membrane bound vesicles found in their endings (ne). Ultrastructural quantitative analysis revealed significant variations in PI elements between winter and summer seasons (F=8.014, p=0.006). DC-II cells characterized by developed biosynthetic machinery and a large pool of secretory granules storage are increased with the ne in winter. However, LC-I cells showing frequent cytoplasmic degranulation are predominant with glc in summer. Thus, important cellular remodelling occurs in the dromedary PI that may depend upon, or perhaps anticipate, external living conditions.

Exploration of the cytotoxic effects of an insecticide, lambda cyhalothrine, on sexual exocrine function in the white rat.

Many xenobiotiques (solvents, pesticides, metals heavy.....) are suspected to be responsible for the fall of the male and female fertility. The purpose of this work is to study the insecticide impact, Lambda-cyhalothrine, managed by oral way during 7 days on the rat testicles histology. Wistar rats were given distilled water (controls) or containing 15,383 mg/kg or 23,075 mg/kg of Lambda-cyhalothrine. The exposure to this insecticide induced an increase in the diameters of the seminiferous tubes. The histological of the seminiferous tubes revealed deteriorations of the germinatif epithelium: blocking of the spermatogenesis, presence of the apoptotic cells and absence of the spermatozoids in certain lumens. All these histological alterations constitute a signs of cytotoxicity of Lambda-cyhalothrine on the male fertility in the Wistar rat.

Exploration of cytotoxic effect of malathion on some rat organs structure.

Widespread use of insecticides has caused several risks to public health. This work was designed to investigate the histological changes in Liver, lung, adrenal medulla and testis of Wistar rats treated with malathion, administered intra peritoneally at a dose of 33,051 mg/kg per day. Exposure to the malathion, for 40 days, induced histological alterations: regular arrangement of hepatocytes with dilated sinusoidal spaces, thickened Lung epithelium, regression of adrenal medulla with congestion and disruption of the germ Line. These alterations represent the signs of cytotoxicity of malathion in Wistar rats.

The pituitary intermediate lobe of the hydrated and dehydrated gerbil. An immunohistochemical and electron-microscopic study.

The pituitary intermediate lobe was studied by immunocytochemistry on semithin sections and by electron microscopy in gerbils (Gerbillus pyramidum) caught in summer and winter in the natural biotope or experimentally submitted to chronic hydration or dehydration. In the gerbil, the intermediate lobe was formed by a predominating population of tightly packed melanotrophic cells the immunocytochemical and morphological features of which were comparable to those described in other mammals. A few typical corticotrophic cells were scattered in the contact zone with the neural lobe. Folliculostellate cells labelled with antibodies against glial fibrillary acid protein and vimentin were interspersed between the glandular cells; they formed small follicles in the vicinity of which the apical cytoplasm contained conspicuous dense granules. Both glandular cell types were innervated by axons most probably colocalizing dopamine and gamma-aminobutyric acid. In the pituitaries from the gerbils caught in winter, as from those having free access to hydrated food, the melanotrophic cells exhibited morphological characteristics of high functional activity. In the gerbils caught in summer or receiving exclusively dry food, the secretory activity of the cells was obviously depressed. The corticotrophic cells were unaffected. These observations raise the question of the role of the intermediate lobe in the adaptation to desert life.