QUANTITATIVE HISTOCHEMISTRY OF THE NEPHRON. III. LACTIC DEHYDROGENASE ACTIVITY IN MAN AND OTHER SPECIES

Serum alkaline phosphatase and γ-glutamyl transferase in acute pyelonephritis

Background

Elevated serum alkaline phosphatase (AP) and γ-glutamyl transferase (γ-GT) are commonly observed in patients with acute pyelonephritis. The goal of this study was to examine the clinical significance of elevated serum AP and γ-GT levels and to explore the mechanisms underlying these changes.

Methods

We examined serum AP and γ-GT levels in 438 patients with acute pyelonephritis. Urine AP/creatinine (Cr), urine γ-GT/Cr, fractional excretion of AP, and fractional excretion of γ-GT (FE_γ-GT) were evaluated in patients with elevated and normal serum levels. AP isoenzymes were also examined.

Results

We identified 77 patients (17.6%) with elevated serum AP and 134 patients (30.6%) with elevated serum γ-GT. Among them, both enzymes were elevated in 64 patients (14.6%). Older age, longer hospital stay, elevated baseline serum Cr, and complicated pyelonephritis were associated with increases in serum AP and γ-GT. Multivariate analysis showed that high serum AP levels were significantly correlated with renal impairment (odds ratio, 2.13; 95% confidence interval, 1.08–4.19; P = 0.029). FE_γ-GT was significantly lower in patients with elevated serum enzyme levels. The liver fraction for AP isoenzyme profile did not increase in patients with elevated serum AP.

Conclusion

Our results demonstrated that elevated serum AP and γ-GT levels are associated with complicated pyelonephritis and renal impairment. Lower FE_γ-GT levels in patients with elevated serum enzymes may be the result of decreased urinary excretion of these enzymes.

Effect of tetracycline on pancreas and liver function of adult male albino rats

The effect of tetracycline, at two doses of 50 and 200 mg kg−1 daily, was studied on pancreatic and liver tissue function for 14 and 21 days in adult male albino rats. For pancreatic function the parameters studied were content of amylase and lipase in pancreas, serum amylase and lipase, serum glucose and faecal fat excretion. For liver function, liver specific enzymes in serum, namely alanine amino transaminase, aspartate amino transaminase and lactate dehydrogenase were estimated. In addition, total lipid, antiperoxidative enzymes and lipid peroxidation were measured in pancreas and liver. The content of amylase and lipase in pancreas showed a small but significant decrease in the rats given 50 mg kg−1 for 21 days and the decrease was much more significant in those receiving the 200 mg kg−1 dose. In pancreas free radical levels show a significant increase and reduced glutathione shows a substantial decrease at the 50 mg kg−1 level and a significant change in these parameters was observed at the 200 mg kg−1 dose. Antioxidant enzymes, superoxide dismutase, glutathione peroxidase, glutathione reductase and catalase, showed a small but significant decrease in the pancreas of the rats treated with 50 mg kg−1 tetracycline. A significant decrease in the antioxidant enzymes level was observed at the 200 mg kg−1 dose. In the liver, free radical levels and reduced glutathione were within the normal range at the 50 mg kg−1 level and significant changes were observed at 200 mg kg−1. The antioxidant status was unaffected in liver after treatment with tetracycline at the 50 mg kg−1 level and a significant decrease was observed at the higher dose. Our results reveal the safe nature of tetracycline with respect to the liver at the lower dose tested, whereas, both the higher and lower doses seem to have detrimental effect on the pancreas as revealed by the rise in free radical levels and decrease in the antioxidant enzyme levels.