Ronald E. McNair Program


LaToya Colenberg
 School: Alcorn State University 
Major: Biology
Mentor: Dr. Sean Wilson 
Expected Graduation Date: May 2007
Organizations and Activities: 
• Honors Student Organization
• Ronald McNair Scholar 
• Americorp Campus Link
• Who’s Who Among America’s College Students
• National Biology Honor Society 
E-MAIL: LColnbrg2003@yahoo.com 

COMMENTS: 
Participating in the Ronald E. McNair Program has truly been and enriching experience.  I have learned more over the course of these six weeks than I thought was possible. Not only was my life enriched academically, but socially as well.  My fellow McNair Scholars have become like family, and I will carry the experiences we have shared forever.  This was truly a great experience.
 

 

ABSTRACT

An Analysis of Changes in Arterial Smooth Muscle Calcium Signaling with Aging


It is well known that with aging there are many physiological changes.  These changes include but are not limited to an increase in arterial stiffness, arterial wall thickening and reduced vascular reactivity (Gros et al., 2002 & Robert, 1999).  According to the information published in the 2004 American Heart Association statistics on heart disease and stroke, more than a third of the 64 million individuals with cardiovascular disease are over the age of 65 in the United States.  The prevalence of stroke, heart attack, and kidney failure increases with age, making it important to understand the aging vasculature.  

  The aim of this project is to discover if excitation mediated intracellular Ca2+ elevations are reduced with aging in mesenteric arterial smooth muscle cells.   The experimental models for this research include murine mesenteric smooth muscle cells from mice that are 4-6 months (mature) and 24-30 months (old).  With these cells, agonists involved in autocrine signaling, paracrine, neurotransmission (synaptic signaling), and endocrine signaling were examined.  These agonists include caffeine, phenylephrine, adenosine triphosphate, arginine vasopressin, and fluflenamic acid. Ca2+ was measured using fura2 AM.  Quality of response was unchanged with aging in cells excited with the agonists caffeine, phenylephrine, and adenosine triphosphate.  There was not a mature data set for arginine vasopressin and flufenamic acid, therefore quality of response with aging could not be determined.  A trend was identified between PE and ATP in which responsiveness decrease in the old for the former and  increase in the old for the latter.  This suggests that with aging, the vasculature may come more dependent on purinergic stimulation rather than adrenergic stimulation.