Medical Student Research Fellowship for Summer 2011
Mentor: Jula K Inrig, MD, MHS
Department: Medicine
Room number: HQ.711E
Mail Code: 8523
Phone number: 214-645-8263
E-mail: jula.inrig@utsouthwestern.edu
Project title: Mechanisms and Treatment of Intradialytic Hypertension (MATCH) - Sodium
Human subjects IRB approved project number (where applicable): 092010-018
Animal subjects IRB approved project number (where applicable):
Project Type (patient-based research, animal-based research, or basic research; this characterization is only to permit a general classification for grouping similar types of projects) Patient-based
Brief Description of Project:
Hypertension is a significant cause of morbidity and mortality in end stage renal disease (ESRD) patients. In vitro studies have shown that human endothelial cells (EC) exposed to small increases in [Na] initiate a sequence of events resulting in vasoconstriction, however, there are no studies evaluating the role of elevated plasma [Na] on EC function and BP in vivo. This study seeks to elucidate the pathophysiologic mechanisms involved with the development of hypertension in patients with ESRD, and determine the effects of positive sodium flux during hemodialysis (HD) on EC function.
To compare the acute effects of 3 different dialysis treatments, 20 maintenance HD patients with intradialytic hypertension will undergo varying sequences of the following dialysis procedures performed weekly in block intervals over the course of a 6-week study: high dialysate-to-plasma sodium gradient with ultrafiltration, high dialysate-to-plasma sodium gradient without ultrafiltration, and low dialysate-to-plasma sodium gradient with ultrafiltration. Following the conclusion of the 6-week study and a 1-week washout period, the chronic effects of high dialysate-to-plasma gradients on endothelial cell function and BP will be assessed. The HD patients will undergo 8-weeks of treatment with high dialysate-to-plasma [Na] gradients and 8-weeks of treatment with low dialysate-to-plasma [Na] gradients and endothelial cell function will be compared by brachial artery flow mediated vasodilation. 44-hour ambulatory BP will be measured before and after high and low dialysate-to-plasma sodium dialysis.
The laboratory techniques to be utilized in this study will include quantitative enzyme immunoassay, reductive chemiluminescence, brachial artery flow mediated vasodilation, ambulatory BP, and central aortic BP.
Previous Research Activities or Publications with Medical Students:
-Catherine Kim, ongoing mentor of T32 (2010-2011)
Abstracts/Oral Presentations with Catherine Kim:
-American Society of Nephrology (1 poster, 1 oral presentation)
-Southern Scientist Clinical Investigation (2 posters)
-National Kidney Foundation Annual Meeting (1 poster)
-World Congress of Nephrology (1 poster)
-American Society of Hypertension (1 oral presentation, 2 posters)
Peer-reviewed publications with Catherine Kim: