In 366 patients with bioptical verified and functional compensated chronic glomerulonephritis the relations between the clinical course types of glomerulonephritis according to Ratner, the histological changes and the tubular homoeostatic parameters of renal function, respectively, were investigated. A reliable connection was found between the clinical course type and special tubular functional parameters. With reference to histological changes the occurrence of a tubulo-interstitial lesion (tiK) is the cause of an excessive disturbance of the renal tubular function. Independently of this, however, the clinical course type of chronic glomerulonephritis may be responsible for the pathological reactive failure of tubular functional parameters. In the case of renal tubular dysfunction in the active nephritic type (ANT) and the nephrotic type with hypertension (NHT), respectively, the occurrence of a tik is much likely. By the lack of reno-tubular dysfunction in ANT and NHT a tik be cannot excluded. In contrast to this, in the inactive nephrotic type (INT) and the nephrotic type without hypertension (NHT), respectively, a tik be can excluded by lack of tubular dysfunction. On the other side, a tubular dysfunction in these groups is not a certain proof of a tik.