Epithelial tissues kidney

The next issue to discuss is the diversity of connexins, i.e. the various isoforms, and species variability. Gap junctional channels exist in a broad variety of tissues including the heart, vascular system, brain, epithelial tissues, uterus, lens cells, pancreas and kidney. However, these tissues are connected by different isoforms of gap junctional connexins which can be distinguished with regard to their molecular weight. These differences are mainly due to various lengths of the C-terminal loop. 

These herbicides damage epithelial tissues, e.g., cornea, nails, skin, kidney, liver and linings of the QX and respiratory tracts. 

Immunohistochemical studies on tissue distribution of P-gp Immunohistochemical studies on tissue-specific distribution of P-gp in fish revealed a pattern similar to that described in mammals, i.e. immunoreactive P-gp occurs in epithelial tissues involved in secretion, absorption or serving a barrier function. Further, P-gp-like proteins were observed at the bile canaliculi of the liver, in the proximal tubules of the excretory kidney, at the endothelia of brain capillaries, in the intestinal tract, exocrine pancreas, operculi, gills, pseudobranch, gas gland, interrenal tissue and skeletal muscle (Table 5). This tissue distribution is in agreement with the assumed role of P-gp in protection against xenobiotics. 

Target organs of As(III)-induced effects are the cardiovascular system (myocardial depression caused by decreased contractility), gastrointestinal tract, epithelial tissues, skin, kidney, and nervous system [10,12,19]. 

Rough, dry, scaly skin increased sinus trouble, sore throat, and abscesses in ears, mouth, or salivary gland increased diarrhea and kidney and bladder stones—A deficiency of vitamin A injures the epithelial tissues throughout the body, and leads to a peculiar type of horny degeneration called keratinization. The epithelial cells form the outer layer... 

Thus, there was a total of 8 rats for evaluation in the control group and 12 in the experimental group. In the control group given an extract of fish alone, there were no neoplastic changes in the stomach or pancreas except an epithelial hyperplasia of the glandular stomach of one rat (Table 1), Instead, there were tumors in the testes, kidneys, and soft tissues, as are often seen in aged rats. 

Histopathological changes were noted in the kidneys of rats administered lead acetate in the drinking water for 76 weeks at lower doses (Roller et al. 1985). These changes, which were observed at a dose of 37 mg/kg/day, a dose much lower than that used by Vyskocil et al. (1989), included necrotic and dilated cortical tubules, tubular protein casts, areas with large nuclei and fibrous connective tissue, and large intranuclear inclusion bodies in the enlarged epithelial cells of the cortex near the cortical-medullary junction. 

P-glycoprotein is not only expressed in tumor cells, but also in cells of several healthy tissues. In liver it was detected in the biliary canalicular surface of hepato-cytes and the apical surface of small biliary ductules. In the small intestine and colon, it is localized in the apical surface of columnar epithelial cells, and in kidneys it is found in the brush border membrane of proximal tubules. Moreover, it is detectable on the apical surface of small ductules in the pancreas and on the surface of cells in the medulla and cortex of adrenals [2]. 

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