An ultrastructural morphometric study of membranous glomerulonephritis.

Sixteen cases of membranous glomerulonephritis and 17 controls were studied using electron microscopy and morphometry of whole glomerular cross-sections. It was found that, in relation to controls, in membranous glomerulonephritis the following parameters are increased: total area, total number of cells, all basement membrane parameters, visceral epithelium compartment area and visceral epithelial cell area, area of parietal epithelium, mesangium and urinary space, number of endothelial and mesangial cells; by contrast, the following are decreased: number of visceral epithelial cells, capillary and endothelial volume fractions. Correlation analysis between morphometric and clinical parameters demonstrated significant correlations between capillary basement membrane thickening and duration of disease, proteinuria and renal function; the changes in visceral epithelial cells correlated with serum albumin, proteinuria and inverse of creatinine; changes in relative area of capillary lumina correlated with blood pressure. It is concluded that the ultrastructural morphometric study of renal biopsies will lead to better understanding of glomerular disease.

Swelling studies of bovine corneal stroma without bounding membranes.

1. The swelling characteristics of demembranated bovine corneal stroma were studied as a function of time and of the pH and ionic strength of the bathing solution. 2. Compared with other pH values, the stroma swelled least near pH 4. 3. In the pH range 6--10, increasing the pH resulted in an increase both in the rate of swelling and in the hydration reached in a given time. 4. At pH 2 and 4, a final constant value of hydration was attained. At higher pH values no such equilibrium was attained when the hydration of the tissue was followed for at least 100 hr. 5. The swelling at high pH values was consistent with the hypothesis that the Donnan-osmotic contribution is the major component of the swelling pressure. 6. The ionic strength dependence was complex. There was a general decrease of swelling with increase in the ionic strength (mu) until around mu = 0.1. The swelling at mu = 0.15 was greater than at mu = 0.1 and mu = 0.25. 7. The results were interpreted on the assumption that the Donnan-osmotic effect is the major component of the swelling pressure.