The Influence of Nicotine Withdrawal on Oxygen Sensing - PROJECT SUMMARY/ABSTRACT CANDIDATE: Dr. Wollman’s career objective is to establish an independent research program investigating the influence of nicotine withdrawal on oxygen sensing. The research and career development plans have been carefully designed to provide the necessary skills for Dr. Wollman to establish a novel, independent line of research and include the following objectives: 1) to gain further expertise in research methodology and techniques, 2) develop teaching and mentoring skills, and 3) to develop grant writing skills and further academic leadership skills. ENVIRONMENT: Primary mentor Dr. Fregosi is an expert in studying breathing both in vivo and in vitro and will provide technical guidance for Aim 1 experiments during the K99 phase. Mentors Dr. Prabhakar is an expert in carotid sinus nerve recordings and patch clamp from carotid body glomus cells, and Dr. Oweiss is an expert in vivo gCaMP imaging, and will provide extensive training to Dr. Wollman during the K99 phase. Both mentors, along with the rest of the assembled advisory committee, will help to ensure Dr. Wollman’s success with this proposal. With the exception of hands on training with Drs. Prabhakar in Chicago and Oweiss in Florida, all of the work proposed here will be carried out in the Fregosi laboratory. Dr. Fregosi has NIH funding and the resources needed to support Dr. Wollman during the training phase of the research project. The University of Arizona College of Medicine is an ideal setting for the mentored phase of this proposal due to the outstanding faculty mentors and facilities available. RESEARCH: My overarching hypothesis is that nicotine withdrawal alters the carotid body and neurons in the nucleus tractus solitarius (NTS), key neural structures that are involved in oxygen sensing. Preliminary data shows that chronic nicotine exposure has no effect on the ventilatory response to hypoxia, however rats show a blunted response to hypoxia after 48 hours of nicotine withdrawal. To build on these novel preliminary data, I have designed the following specific aims. Aim 1: To test the effects of nicotine withdrawal on the ventilatory response to 10, 12, or 15% hypoxia, and to test the ability for an acute dose of nicotine to rescue this response. Aim 2: To test the effects of nicotine withdrawal on oxygen sensing in the carotid body, NTS neuron activation and the respiratory motor output from the phrenic nerve in vivo. Aim 3: To test the effects of nicotine withdrawal on nicotinic acetylcholine receptor function in carotid body glomus cells and NTS neurons in vitro. This work will be carried out using plethysmography, a unique combination of in vivo calcium imaging using fiber photometry, and concurrent phrenic nerve recordings, and whole cell patch clamp of glomus cells in excised carotid bodies and NTS neurons in a brainstem slice. The proposed training plan will allow Dr. Wollman to learn new experimental techniques, successfully complete the proposed research and transition to an independent, extramurally-funded tenure-track position at a top-tier (R1) research institution.
