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Show SCHOOL OF MEDICINE AND HEALTH SCIENCES iNDERGRADUATE RESEARCH ABSTRACTS AGING AND VASCULAR INJURY Elizabeth Nielson (Anthony J. Donato) Division of Geriatrics University of Utah Cardiovascular disease is the leading cause of death in the United States. Age increases the prevalence of cardiovascular disease. The factor I have investigated is whether or not increased cardiovascular disease with age m a y be an exaggerated negative response to vascular injury and altered blood flow dynamics. Previous work done by Dr. Anthony J. Donato and Dr. Lisa Lesniewski has shown that mice have decreased artery function with age. This includes reduced ability to dilate to a stimulus as well as increased artery stiffness. Increased oxidative stress and inflammation are the mechanisms for reduced artery function. Injury to an artery can result in pathological remodeling of the artery. This is indicated by a decrease in lumen diameter and an increase in wall thickness, which results in reduced blood flow and a stiffer artery. Partial carotid ligation has been used in mice to model disturbed flow. We used young (~6 months) and old (-30 months) B6D2F1 mice. Partial carotid ligation is performed on the left carotid artery. Briefly, under anesthesia, the left carotid artery is exposed. Three of the four branches of the artery are ligated with silk suture. The incision is closed and mice are allowed to recover. Three weeks after ligation, mice are sacrificed. The carotid arteries are dissected en bloc with the trachea and esophagus and embedded in OCT. The en bloc dissection allows for comparison of the right and left carotid arteries at the same distance from the heart. My hypothesis for the fall semester of research was that partial carotid ligation will cause greater immune cell infiltration and gene expression for factors related to oxidative stress, inflammation, senescence, and apoptosis in the arteries from old mice compared to young mice. In addition, mice fed a high fat diet will result in greater development of atherosclerotic plaques in the partially ligated arteries from older mice compared with younger mice. My preliminary results show that the artery wall was indeed thicker following partial carotid ligation. However, contrary to m y hypothesis, mice fed a high fat diet did not show any significant difference in the lumen diameter or wall thickness after the ligation. I a m currently performing the histological analysis to determine if, despite a similar wall thickness, there are more lipids in the wall itself. Sfi*fc* Method of h o w PCL is done Right Antegrade Blood Flow Right Carotid Artery (non-ligated) Left Carotid Artery (ligated) Lett Antegrade Blood R o w Right Wall Thickness £ 0 08 Anthony J. Donato H 0.08 Left Wall Thickness for three weeks, including before and after surgery Right Carotid Antegrade Blood Flow for three weeks, including before and after surgery - Left Carotid Antegrade Blood Flow for three weeks, including before and after surgery Right Wall Thickness for three weeks, including before and after surgery 125 |