Peroxisome through cell differentiation and neoplasia.

Peroxisomes are essential in cellular metabolism as their dysgenesis or defects in single enzymes or impairment of multiple peroxisomal enzymatic functions have been found in several inherited metabolic diseases with serious clinical sequelae. The assembly and formation of these cytoplasmic organelles constitute a major and intriguing research topic. In the present study the biogenesis of peroxisomes and the developmental patterns of their enzymes have been reviewed during embryonic and/or post-embryonic ontogenesis of lower (amphibians) and higher (avians, mammals) vertebrates.

Peroxisomal enzymes in normal and tumoral human breast.

The presence of peroxisomes and their enzymatic content were investigated and compared in healthy and neoplastic human breast epithelial cells using cytochemical studies at the ultrastructural level as well as Western blot and biochemical analyses. Ultrastructural cytochemistry revealed the presence of these organelles in both normal and neoplastic breast tissues. Their mean diameter was 0.

The angiotensin I converting enzyme inhibitors, captopril and Wy-44,655 attenuate the consequences of cerebral ischemia in renovascular hypertensive rats.

Global cerebral ischemia (four vessel model) was induced in renovascular hypertensive rats (two kidney, one clip model) chronically treated with intraperitoneal administration of angiotensin I converting enzyme inhibitors, either captopril (100 mg/kg per day) or Wy-44,655 (10 mg/kg per day). Mortality following cerebral ischemia was higher in renovascular hypertensive rats than in normotensive controls. Reduction of blood pressure with captopril or Wy-44,655, lowered mortality.