Effect of oral glucose tolerance test on urine sodium excretion in obese and non-obese pre-menopausal females

We have investigated the changes in urinary sodium excretion during an oral glucose tolerance test [OGTT] through the associated changes in plasma atrial naturetic peptide [ANP], endogenous insulin and renal kallikrein excretion, in 10 normatensive obese and 10 healthy non-obese pre-menopausal females. Baseline blood glucose did not differ between obese and non-obese females. Blood glucose levels during the OGTT were significantly higher in obese than in non -obese females [P<0.01]. Obese females had significantly higher values of serum insulin at baseline and 2 hours after oral glucose load in comparison to non-obese females [P<0.01, <0.0001 respectively]. A similar finding was also obtained regarding fasting insulin resistance index [FIRI][P<0.0001] Prior to OGTT, urine sodium and kallikrein excretion did not differ between obese and non-obese subjects. After oral glucose load there were significant reduction of urine sodium [P<0.0001] and kallikrein excretion [P<0.0001] only in non-obese females. Obese females had insignificant decrease in urine sodium excretion and insignificant increase in urine kallikrein excretion. The decrease in urine sodium excretion was similar in obese and non-obese females. The plasma ANP level was significantly higher both in obese [P<0.0001] and non-obese [P<0.0001] females after glucose load. However, the percent increase was less in obese than in non-obese females [P<0.05]. In conclusion, changes in endogenous insulin induced by oral glucose were associated with a similar decrease in urine sodium excretion in obese and non-obese normatensive pre-menopausal females but the decrease was only significant in non-obese females. Insignificant reduction in urine sodium excretion in obese females could be due to the counteracting natriuretic effects of renal kallikrein and ANP

Long-term caffeine administration to mice could be hepatotoxic? Biochemical, histological and histo-chemical studies

The aim of this work was to assess the chronic effects of caffeine intramuscular administration on some metabolic functions of the liver, glycogen and protein contents of the muscle compared with the histological study of the liver of adult male white mice [Mus musculus]. After 7 days intramuscular injection of caffeine [60 mg/kg body weight] to mice [Mus musculus], it was found that glycogen content of liver and muscle was significantly decreased as compared to the control group together with significant increase in the blood and tissue glucose. The insulin level was also significantly increased. These metabolic changes were continued for 45 days and proved histochemically using Best's carmine stain. After 45 days, the hepatocytes showed marked depletion of glycogen content. The total serum and liver protein showed significant increase as compared to the control group after 7 and 45 days together with disturbed some liver function tests as serum glutamic oxaloacetic transaminase [SGOT], serum glutamic pyruvic transaminase [SGPT] and alkaline phosphatase [AP] which showed significant increase after 7 and 45 days intramuscular caffeine injection. The chronic use of caffeine in pharmaceutics should be restricted as it was proved to cause some hepatocellular and muscular metabolic disturbances