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Glutathione is a nonenzymatic antioxidant synthesized by most animal cells and is depleted in inflammatory bowel disease. The effects of glutathione depletion on intestinal histology and inhibitory neurochemicals was examined in a mouse model. Glutathione depletion in A/J mice involved inhibition of gamma-glutamylcysteine synthetase using L-buthionine-(S,R)-sulfoximine (BSO) for 10 days. Ileum and colon were obtained from saline-control mice, BSO-treated mice, and BSO-treated mice receiving ascorbate or glutathione monoethylester. Glutathione, lipid peroxides, and nicotineamide adenine dinucleotide phosphate diaphorase activity were measured by colorimetric assays. Vasoactive intestinal peptide was measured by radioimmunoassay. Glutathione depletion induced enlargement of mucosal-submucosal lymphoid aggregates without germinal centers in ileum and colon. These aggregates were prevented by supplementation with glutathione monoethylester but not ascorbate. Tissue levels of inhibitory neurochemicals were unchanged. Depletion of glutathione appears to induce enlarged lymphoid aggregates by recruitment of lymphocytes from the peripheral circulation. A component of the inflammation that develops in inflammatory bowel disease could be related to depletion of tissue levels of glutathione. [ABSTRACT FROM AUTHOR]

Transplantation of the small intestine is a neural model that could include extrinsic denervation, loss of intrinsic enteric neurons, or loss of intrinsic neural pathways. Nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase activity was measured in normal rat ileum, ileum 3 months after resection of the jejunum, and ileum 3 months after isotransplantation of the ileum. The distribution of NADPH diaphorase activity and immunoreactive neuronal nitric oxide synthase were examined. Nicotinamide adenine dinucleotide phosphate diaphorase activity was increased in transplanted ileum (16.5+/-3.5 mU/mg protein) compared to normal controls (6.6+/-0.7) and resection controls (6.8+/-0.6) (P < 0.05, ANOVA). Histologically, NADPH diaphorase activity and immunoreactive nitric oxide synthase appeared increased within nerve cell bodies following transplantation. These findings may represent an adaptive response of the enteric nervous system to extrinsic denervation. Loss of intrinsic neural pathways was not supported as a mechanism.

Hyperbaric oxygen (HBO) promotes tissue healing by increasing oxygenation. Therefore, HBO therapy is clinically useful for some patients who have undergone major cancer resection and/or radiotherapy to the head and neck. For individual patients, however, there might be undetected viable tumor present at the time of therapy. This study was performed to determine if increased tissue oxygen had a measurable effect on the growth of squamous carcinoma xenotransplants which had been derived from head and neck cancers. After the successful growth of two well-established human squamous cell carcinoma cell lines (183 and 1483), each tumor was transplanted into 20 mice. Every mouse received four transplants of 10(6) cells. Ten mice with 40 xenotransplants in each group were treated with HBO daily for 90 minutes at a pressure of 2 atm, whereas the other 10 formed the control group. The mice transplanted with cell line 1483 were treated for 21 days; mice transplanted with cell line 183 were treated for 28 days. The tumor weight, volume, and histology were evaluated. No significant difference was found between experimental groups. This study suggests that increased tissue oxygen neither significantly increases nor decreases the growth of squamous cell carcinoma.

The method described here using a centrifuge and Coulter Cell Counter for the quantitative differential agglutination of human red cells uses commercial anti-A and anti-B antisera for the ABO system, and for the Rh system a commercial anti-D serum, a low ionic strength solution and an anti-human IgG antiserum. We compared this Coulter Counter method with the Technicon AutoAnalyzer method which utilizes bromelin and polyvinyl pyrrolidone, and anti-A, anti-B and anti-CD antisera, and found this new method to be the simpler of the two. The nonagglutinable count with the Coulter Counter was 1.07% for A1 red cells, 2.26% for A2 red cells, 1.06% for B red cells, and 1.78% for Rh-positive red cells, results similar to those seen with the Technicon AutoAnalyzer. Results with the Coulter Counter method were consistently accurate whether the ACD red cells were studied on the day of collection, after 10 days of 4 degrees C storage, or after 4 degrees C storage for up to 6 days followed by cryopreservation with 40% (w/v) glycerol at-80 degrees C, thawing and washing. In this study, red cell samples obtained from recipients who had received compatible but identifiable donor red cells were frozen with 40% glycerol and stored at-80 degrees C for 10 months, thawed and washed. Survival measurements on these washed previously frozen red cells were similar to the values in liquid-stored red cells.