Effect of linoleic acid hydroperoxide on liver microsomal enzymes in vitro.

Rat liver microsomes incubated with linoleic acid hydroperoxide (LAHPO) lost cytochrome P-450 specifically among the enzymes of microsomal electron transport systems. The loss of cytochrome P-450 content and glucose-6-phosphatase activity by LAHPO was accompanied by an increase in malondialdehyde (MDA) production. Turbidity of microsomal suspensions was decreased with increasing MDA production, but not proportionately. Diethyldithiocarbamate (DTC), N,N'-diphenyl-p-phenylenediamine and alpha-tocopherol inhibited almost completely the LAHPO-induced MDA production of microsomes, however no perfect protection against the loss of cytochrome P-450 content and glucose-6-phosphatase activity was observed. The decrease of microsomal turbidity by LAHPO was little affected in the presence of DTC. Purified cytochrome P-450 was destroyed by LAHPO, with minimal protection by the compounds described above. These results suggest the possibility that the loss of microsomal enzyme activities during lipid peroxidation may be attributed largely to a direct attack on enzyme proteins by lipid peroxides rather than indirectly to a structural damage of microsomal membranes resulting from peroxidative breakdown of membrane lipids.     

A case of double pylorus.

Doubling of the pyloric channel is one of the rare anomalies of the intestinal tract. There have been 23 cases of double pylorus that we have been able to find in the literature. As the etiologic aspects of double pylorus the majorities of the cases were thought to be acquired lesions from ulcer disease except three cases. We present a case of double pylorus which seems to be acquired lesion, with a review of the literature.