Division FACULTY LIST
rapidly initiate the release or activation of factors that signal the kidney to produce an acute increase in renal potassium excretion. To test this axis in humans, researchers conducted a series of potassium handling experiments in random order that demonstrated a rapid increase in potassium excretion with no increase in serum potassium concentration that persisted despite blocking the hormone aldosterone. These findings suggest that a mechanisms for potassium excretion exists independent of the classical physiological mechanisms. The experiments provide data that supports the existence of a novel gastrointestinal-renal kaliuretic signaling axis in humans that mediates a share of the potassium excretion that follows a complex potassiumcontaining meal independent of changes in serum potassium concentration and aldosterone. This axis appears to function alongside the known mechanisms mediated by changes in extracellular potassium concentration and may offer an auxiliary mechanism for potassium excretion.
Pharmacokinetics in the study of how the body processes a medication A large study of the pharmacokinetics and safety of a new antibiotic drug in patients with liver disease was conducted in 2014-2015. Specifically, the Division studied the absorption from the stomach and gastrointestinal tract, distribution within the body, and the elimination by the kidneys and liver of a medication. The study of the pharmacokinetics and safety of new medications is a central mission of the Clinical Pharmacology Research Unit. The Clinical Pharmacology Research Unit has an international reputation for conducting complex
Richard A. Preston, MD, MSPH, MBA Division Chief Professor of Clinical Medicine
Professor of Medicine Barry J. Materson, MD, MBA
Research Associate Professor David Afshartous, MD
pharmacokinetic studies in patients with kidney and liver disease. The Division recently conducted a large study of a new antibiotic medication that included 24 study participants with liver disease and 24 matching healthy volunteers. Normally such a large study would be divided between several centers. The results of this study suggest that this new medication is safe in patients with liver disease and requires no dose adjustment. The testing of new medications in patients with kidney and liver disease are key steps in the drug development and approval process
HOW SALT RAISES BLOOD PRESSURE TO CAUSE HYPERTENSION This past year, the Division continued its work towards understanding how the kidney regulates the amount of sodium in the body and helps to control blood pressure. The kidney is responsible for maintaining total body sodium within a range that is suitable for normal blood pressure as well as control of the body’s fluid volumes. The goal of these studies is to better understand a newly discovered pathway by which certain sodium transporters in the kidney regulate the amount of sodium that the kidney excretes. The results of this interesting study should be available in the coming year 2016-2017.
Miriam Gonzalez Sosa, MA prepares to collect blood samples for pharmacokinetic and safety laboratory analysis. The Clinical Pharmacology Research Unit conducts approximately 15-20 clinical research studies each year in a variety of patient populations.
D epar t men t o f Medi c in e C h air man ’s R e po r t 2015
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