Mesangium in rats after E. coli neurotoxin shock: a morphometric and light microscopic analysis.

The renal corpuscles of 28 specific-pathogen-free Wistar rats fixed by perfusion were examined light microscopically and morphometrically following experimental protracted neurotoxin shock. The mean diameter of the center sections of 420 renal corpuscles was 113.0 micrometers. The mesangial portion occupied 9.5% of the total area of the renal corpuscle in control rats and increased to a maximum of 17.25% in experimental rats. The number of mesangial nuclei per renal corpuscle in rats with protracted shock showed that expansion of the mesangium with compression of capillary loops was not caused solely by an increase in the number of cells. Furthermore, there was an enlargement of the mesangial cytoplasm and matrix. Activation and proliferation of connective tissue in rats with protracted shock could be observed in the interstitium of various organs as well as in the mesangium of the glomerulus.