Adrenergic Reactivity and Coronary Flow Reserve of SVF Cell Types

Grade Level at Time of Presentation

Junior

Major

Biology

Minor

Chemistry, Studio Art

Institution

University of Louisville

Department

Department of Physiology and Biophysics

Abstract

Adrenergic Reactivity and Coronary Flow Reserve of SVF Cell Types: CD11b+Enriched and CD11b-Depleted

Bailey Beery, Natia Kelm, Jason Beare, Fangping Yuan, Amanda LeBlanc

Department of Physiology and Biophysics

Introduction: Past studies in our lab showed that an intravenous injection of adipose-derived stromal vascular fraction (SVF) cells into old rats improved the adrenergic and increased the coronary flow reserve in vivo. Going forward, we wanted to determine which specific cell population in the SVF could be the mechanism of action. Our hypothesis was that the cells from the SVF, causing the increased coronary flow and improved adrenergic function was a resident immune cell type (CD11b+), which regulates leukocyte adhesion and migration to areas of inflammation.

Methods: Three groups of 24-month old Fischer 344 female rats were used: old control (saline treated), CD11b+ enriched (), and CD11b- depleted (). The rats received cardiac ultrasound measurements at baseline and four weeks post-injection. After heart explant, the left anterior descending (LAD) coronary arterioles were isolated and treated with dobutamine (), norepinephrine (, and norepinephrine with 2atenolol (. Luminal diameters of the pressurized vessel were measured.

Results: The in vivo ultrasound studies showed a 69.7% increase post-injection in aged rates treated with CD11b- cells (p=0.013). There were no significant differences between the groups at baseline or at 4-weeks. There was no difference in the isolated vessel studies to adrenergic agonists in any of the groups.

Conclusions: Contrary to our hypothesis, the CD11b+enriched cell type from SVF is not the cause of the increased adrenergic reactivity or CFR in our cell-treated aged rats. The CD11b-depleted cells resulted in increased CFR, but did not alter isolated coronary vessel function. Future studies will determine which cell type(s) of the 11b- fraction contributed to both increased adrenergic reactivity and coronary blood flow.

This document is currently not available here.

Share

COinS
 

Adrenergic Reactivity and Coronary Flow Reserve of SVF Cell Types

Adrenergic Reactivity and Coronary Flow Reserve of SVF Cell Types: CD11b+Enriched and CD11b-Depleted

Bailey Beery, Natia Kelm, Jason Beare, Fangping Yuan, Amanda LeBlanc

Department of Physiology and Biophysics

Introduction: Past studies in our lab showed that an intravenous injection of adipose-derived stromal vascular fraction (SVF) cells into old rats improved the adrenergic and increased the coronary flow reserve in vivo. Going forward, we wanted to determine which specific cell population in the SVF could be the mechanism of action. Our hypothesis was that the cells from the SVF, causing the increased coronary flow and improved adrenergic function was a resident immune cell type (CD11b+), which regulates leukocyte adhesion and migration to areas of inflammation.

Methods: Three groups of 24-month old Fischer 344 female rats were used: old control (saline treated), CD11b+ enriched (), and CD11b- depleted (). The rats received cardiac ultrasound measurements at baseline and four weeks post-injection. After heart explant, the left anterior descending (LAD) coronary arterioles were isolated and treated with dobutamine (), norepinephrine (, and norepinephrine with 2atenolol (. Luminal diameters of the pressurized vessel were measured.

Results: The in vivo ultrasound studies showed a 69.7% increase post-injection in aged rates treated with CD11b- cells (p=0.013). There were no significant differences between the groups at baseline or at 4-weeks. There was no difference in the isolated vessel studies to adrenergic agonists in any of the groups.

Conclusions: Contrary to our hypothesis, the CD11b+enriched cell type from SVF is not the cause of the increased adrenergic reactivity or CFR in our cell-treated aged rats. The CD11b-depleted cells resulted in increased CFR, but did not alter isolated coronary vessel function. Future studies will determine which cell type(s) of the 11b- fraction contributed to both increased adrenergic reactivity and coronary blood flow.