Expression of Neuropeptide Y, Substance P, and their receptors in the right atrium of diabetic patients.
OBJECTIVE
To investigate the expression of neuropeptides and their receptors that play a role in cardiac homeostasis in the right atrium of nondiabetic and diabetic patients undergoing coronary artery bypass graft surgery.


BACKGROUND
The cardioactive neuropeptides and their receptors investigated in this study were Neuropeptide Y (NPY), and its receptors, NPY Receptor1 (NPY1R), NPY Receptor2 (NPY2R), NPY Receptor5 (NPY5R) and Substance P (SP) and its receptor, Neurokinin1R (NK1R).


METHODS
The gene and protein expression of NPY, NPY1R, NPY2R, NPY5R, SP and NK1R from the atrial tissue of 10 nondiabetic and diabetic patients undergoing coronary artery bypass grafting (CABG) was assessed by Q-RTPCR, immunohistochemistry, Western blot, and ELISA.


RESULTS
Gene expression of NPY2R, NPY5R, preproTachykinin A (SP gene), and NK1R and their respective protein expression were significantly reduced whereas that of NPY and NPY1R were unchanged in the right atrium of diabetic patients compared to nondiabetic patients.


CONCLUSIONS
These results demonstrate that the expression of neuropeptides and their receptors in the diabetic heart is significantly impaired, and may be the link between neuropathy and cardiac complications. Further studies are warranted to delineate pathophysiologic mechanisms associated with dysregulation of the cardiac neuropeptide system and the relationship to cardiac complications in diabetes.
Department of Surgery, Division of Vascular and Endovascular Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
Asma
A
Ejaz
Frank W
FW
LoGerfo
Kamal
K
Khabbaz
Leena
L
Pradhan
D000368:Aged; D003920:Diabetes Mellitus / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D006325:Heart Atria / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008875:Middle Aged; D009478:Neuropeptide Y / Q000378:metabolism*; D018040:Receptors, Neurokinin-1 / Q000235:genetics / Q000378:metabolism*; D017476:Receptors, Neuropeptide Y / Q000235:genetics / Q000378:metabolism*; D013373:Substance P / Q000378:metabolism*
D009478:Neuropeptide Y; D018040:Receptors, Neurokinin-1; D017476:Receptors, Neuropeptide Y; C097212:neuropeptide Y-Y1 receptor; D013373:Substance P