Quantitative Histochemistry of the Nephron. V. Alkaline Phosphatase and Lactic Dehydrogenase Activities in Lupus Nephritis*

Abstract

The natural history and histological development of lupus nephritis have been studied in detail in our laboratory (1, 2). The glomeruli were more severely involved histologically than were the tubules at all stages of development of lupus nephritis. In the early stages (lupus glomerulitis) the histological abnormalities were confined to the glomeruli. Only when the glomerular involvement became considerably more severe was there histological evidence of tubular degeneration and interstitial fibrosis and inflammation (lupus glomerulonephritis). Even in lupus glomerulonephritis, histological abnormalities of the tubules and interstitial tissue were considerably less severe than in other types of glomerulonephritis. These histological observations were reflected functionally, in that ability to concentrate the urine and to excrete phenolsulfonphthalein were preserved until comparatively late in the disease.In a previous paper of this series (3) the alkaline phosphatase and lactic dehydrogenase (LDH) activities of individual anatomical and functional units of the nephron were reported for healthy kidneys, and for a variety of diseases which affect primarily the renal tubule, i.e., diseases associated with a functional imbalance between tubules and glomeruli. In this paper, the results of assays of the activities of these two enzymes will be reported for lupus nephritis-a disease in which there appears to be histological and functional imbalance between glomeruli and tubules.

Quantitative Histochemistry of the Nephron. Iv. Alkaline Phosphatase and Lactic Dehydrogenase Activities in Renal Tubular Diseases*

“…In lupus glomerulonephritis, for example, where the tubular degeneration was of a comparatively mild degree, increased LDH activity was found in the convoluted tubules (10). There was no evidence of severe impairment of renal function in this disease, and glucose, inorganic phosphate, and amino acids appeared to be reabsorbed normally by the tubules.…”

“…In the single patient with familial renal glycosuria studied, the alkaline phosphatase activity in the proximal convolution was decreased to approximately 50 per cent of that found in proximal convolutions from healthy kidneys. The decrease of alkaline phos- [10] [11]…”

Quantitative Histochemistry of the Nephron. Vi. Hydroxyproline in the Human Glomerulus*

“…However, it must be remembered that all elements of the glomeruli increase in weight during growth. Elsewhere we have shown that the average dry weight of 130 healthy glomeruli dissected out from 16 p sections was 42.1 mng in the adult (15); that of 106 healthy glomeruli similarly dissected out from 16 pu sections of kidney in infants (1 day to 5 months old) was 24.3 meg. This resolves partially the apparent contradiction between our chemical findings and the electron microscopic observations.…”

Studies of Human Kidney and Urine Acid Phosphatase

“…Elevated urinary enzyme activ ity was found in a patient with renal tubular acidosis, pyelonephritis, nephrocalcinosis, and hypokalemia [28]. In unilateral and asymmetric 14,20,[22][23][24][25]. There bilateral renal diseases, including chronic glomerulonephritis, chronic pyelonephritis, idiopathic hematuria and proteinuria and renal artery stenosis, increased urinary acid phosphatase activities were observed from the predominantly involved kidney [27].…”