Non-immunological factors have been proposed to induce the aggravation and progression of glomerular injury in patients with chronic renal glomerulonephritis. In this experiment, we fed Masugi nephritis rats with various groups of chaw for three to four months after receiving uninephrectomy. We then studied clinically and morphologically each group of rats. The rats fed with chaw containing salt (8%) and protein (24%) showed the highest level of blood pressure (180 mmHg), a moderate incense of proteinuria, and severe glomerular injury. The rats fed with salt in the protein rich (50%) chaw showed a lesser degree of hypertention (160 mmHg) ; however, this group showed the largest amount of proteinuria and the most severe form of glomerular and tubular injury. The sera taken from these rats demonstrated the highest level of DuN (100+17 mg/dl) and Creatinine (1.8±0.2 mg/dl). The rats fed with the protein poor (6%) chaw showed normal blood pressure, a decreasing amount of proteinuria and a mild form of glomerular injury. Lesser and better results of these lesions were obtained in the rats fed with the protein poor chaw containing the essential amino acids. Furthermore, the aggravation of the glomerular injury induced by feeding with salt in the protein rich chaw for 1 month recovered after changing the chew to that of the protein poor chaw containing the essential amino acids; the results also showed a decrease in the amount of proteinuria and a morphological improvement. The results obtained suggest that too much intake of protein and salt lead to the aggravation of glomerular injury, whereas the restriction of protein and salt intake have a protective effect on glomerular injury in patients with chronic glomerulonephritis.
