Effects of vincristine on the bile flow in male albino rats.

Bile secretion is an important function served by the liver. The microtubular system integrity plays a key role in hepatic transport and excretion of several of bile constituents including phospholipids & cholesterol as well as detoxified xenobiotics. Furthermore, an alteration in bile secretion has been proposed as an important cause of enteritis, also a complication of microtubular inhibitors like Vincristine (VCR) that may occur following treatment as an anti cancer drug. The study aims to study the effects of microtubule inhibitor VCR on bile flow and bile composition in rats. For this purpose, male albino rats were studied. One group of five rats was infused with single IV dose of VCR (@1 mg/kg and the other received equal volume of IV vehicular fluid. For bile samples, animals were cannulated, bile flow examined at different time intervals before and after drug administration. Biliary composition studied at second hour post i/v administration. Single dose VCR treatment showed significant rise in the baseline excretion of bile in animals studied during first 2 hrs, although, there was a mild reduction in the biliary flow rate after few hours. Biliary total cholesterol was decreased and cation concentrations increased significantly in the second hour post VCR. The results indicate that the exposure of rats to VCR induces early alterations in biliary secretion. This study may prove useful for the purpose of understanding enteritis in patients undergoing chemotherapy.

Adiposity: Determinant of peak expiratory flow rate in young Indian adults male.

Background. Although several factors such as respiratory muscle strength, lung compliance, resistance to airflow, and even obesity affect the lung functions, the nature of relationship with markers of adiposity is not clear. We hypothesised that central pattern of fat distribution is a significant predictor of decreased peak expiratory flow rate (PEFR). The present study was designed with the aim to examine the effects of adiposity on PEFR in males. Methods. One hundred young healthy male volunteers were analysed in the study. They were classified into non-obese, and obese groups based on body mass index (BMI) (obese ≥30Kg/m2 and non-obese <30Kg/m2). The PEFR was measured by using Wright’s peak flow meter. Data was analysed using unpaired ‘t’ test for statistical significance of differences between the non-obese and the obese, stratified into age groups of 20 to 30 years and 30 to 40 years. A partial correlation adjusted to age, height and BMI followed by regression analysis was conducted using adiposity markers as a predictor of PEFR. Results. The model adjusted to age, height, weight and BMI revealed waist hip ratio (WHR) as the only parameter which shows significant variance in PEFR with a Pearson’s r=-0.59, F (1, 100)=12.23, p=0.04. The resulting linear regression equation is y=-388.72xWHR+850.68. Conclusions. Our findings suggest that obesity itself and especially the pattern of body fat distribution have independent effects on PEFR. These results suggest that abdominal adiposity, measured as WHR, is a better predictor of expiratory flow than weight or BMI.

Abdominal obesity and pulmonary functions in young Indian Adults : A prospective study.

Obesity is a global health hazard and has been linked to numerous metabolic complications such as dyslipidemia, type II diabetes, & cardio vascular diseases and is negatively associated to the pulmonary function. The mechanism for this association is still debated and the best marker of adiposity in relation to dynamic pulmonary function is still not clear. We assessed the association of respiratory parameters and body mass index (BMI), waist circumference (WC) and Waist Hip ratio (WHR) as the markers of relative and abdominal obesity adiposity respectively. Step wise linear regression analysis was used to find out the association of FVC and FEV1 (performed in standing) with over all and adiposity markers stratified by gender and adjusted to height and age. A random sample of volunteers (n=80) from general population in and around Dehradun, India of age group 20-40 years. In women the WC shows a higher negative association to respiratory parameters FVC and FEV1 {B (P value), R2 as – 0.381(0.017), 0.122 and – 0.373(0.019), 0.139} while all the adiposity markers showed a negative significant association. In men WC showed highly significant negative association with FVC and FEV1 {Beta (P value), R2 as – 0.502(0.001), 0.232 and – 0.428(0.006), 0.184} with higher R2 values as compared to other adiposity parameters. The result suggested that the abdominal obesity marker is an important and better predictor of pulmonary function than BMI and the investigators suggest the inclusion of it as a potential confounding factor when investigating the determinants of pulmonary function.

Hepatotoxic effects of vincristine: An experimental study on albino rats.

Vincristine (VCR) is an established drug of choice in treatment of some myelomas, lymphomas and leukemias. Hepatotoxicity is a lesser studied side effect of the drug. Samples of blood and other tissues were collected for morphological, biochemical and histopathological evaluation 2 and 24 hours after single intravenous administration of 1.0 mg/kg of VCR to male Albino Wistar rats. VCR produced weight loss; and elevated serum alkaline phosphatase (515.20±356.22, P<0.05), SGPT (192.00±102.62, P<0.05), and SGOT (574.20±292.16, P<0.05) even after 24 hours of drug administration. Though these changes were most severe during the first 2 hours of VCR administration, they also persisted till 24 hours, which may suggest a possibility of an enterohepatic circulation of the drug or its metabolites. This was complemented with morphological disruption in hepatocytes on light and electron microscopy including Scanning Electron Microscopy and Transmission Electron Microscopy.