Project Summary
Males and females differ in their basic physiology and pathophysiology in essentially all physiological systems.
These biological sex differences can lead to differences in disease prevalence, progression rates and treatment
outcomes. Understanding these differences can serve to identify new disease mechanisms and/or new and
improved therapeutic opportunities. Thus, there is an immense need for additional research into the area of sex
differences in both animal models and people. Acid-base homeostasis is of critical importance for maintaining
normal health and renal ammonia metabolism has a major role in the maintenance of acid-base homeostasis. I
have shown there are significant sex differences in basal ammonia excretion that result from sex differences in
the expression of multiple important proteins involved in ammonia metabolism and transport. Furthermore, I
have shown that there are significant structural differences between the female and male kidney. Hence, the
overall objective of this proposal is to determine the underlying mechanisms of these sex differences in renal
ammonia metabolism and to determine the role of these sex differences in physiological relevant disease
models. This objective will be evaluated via the following specific aims: 1) determine the role of sex steroid
hormones in the regulation of renal ammonia metabolism using a gonadectomy and hormone replacement
model; 2) determine the role of sex steroid hormone receptors in the development of sex-dependent differences
in ammonia metabolism through the use of kidney-specific AR and ERa deletion; 3) determine the role of sex
chromosomes in the regulation of renal ammonia metabolism using the four core genotype model; and, 4)
determine the effect of sex on the renal response to conditions of altered ammonia metabolism such as metabolic
acidosis. Autumn Harris, DVM, DACVIM (SAIM), is an NIH T32-funded post-doctoral research fellow at the
University of Florida College of Medicine. This career development award will provide Dr. Harris with the
additional training needed to achieve her goal of becoming an independent investigator, which includes training
in the areas of 1) study design and implementation, 2) performance, interpretation, and evaluation of various
laboratory techniques and diagnostic tests, 3) statistical methods and interpretation, 4) collaboration with a
multidisciplinary and multi-institutional team, 5) grant and manuscript writing. Dr. Harris has developed a
comprehensive program including didactic training, practical and laboratory experience, and a strong mentoring
and advisory team. The University of Florida College of Medicine will provide a collegial and supportive
environment with the equipment, laboratory space, and resources necessary to complete the research and
training. At the culmination of this proposal, Dr. Harris will be poised to achieve independence as a researcher
with continuing investigation in the field of nephrology and sex differences.