Inhibition of NF kappa B activation by pyrrolidine dithiocarbamate prevents in vivo hypoxia/reoxygenation-mediated myocardial angiogenesis.
This study sought to examine the effect of nonlethal moderate whole body hypoxic challenge (10% 02/90% N2) on rat myocardial angiogenesis. Sprague Dawley rats were subjected to 4 h of systemic normobaric hypoxemic hypoxia (10 +/- 0.4% O2) in an anesthesia chamber or to 4 h of normoxia (ambient 20.9 +/- 0.4% O2) to time-match the duration of hypoxia. All rats were then kept under normoxic conditions. Rats were sacrificed and hearts harvested either after 2 h for subsequent electrophoretic mobility gel shift assay for NF kappa B, or after 24 h for subsequent Western blot analysis for vascular endothelial growth factor (VEGF) and after 7 days for immunohistochemistry for capillary density measurement. We also used pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF kappa B, before 1 h of hypoxia to establish the possible role of NF kappa B in modulating myocardial angiogenesis. The results showed significant induction of VEGF protein expression after 4 h of hypoxia followed by 24 h of reoxygenation in the rat myocardium. The DNA binding activity of NF kappa B was increased compared with the hypoxic group. However inhibition of NF kappa B by PDTC decreased capillary density significantly when compared with the hypoxic group. These findings demonstrate the role of NF kappa B and VEGF in myocardial angiogenesis for the first time.
Sasaki
H
H
Department of Surgery, University of Connecticut Health Center, Farmington, Connecticut, USA.
Zhu
L
L
Fukuda
S
S
Maulik
N
N
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D015153:Blotting, Western; D002196:Capillaries / Q000187:drug effects; D003326:Coronary Circulation / Q000187:drug effects; D016228:Endothelial Growth Factors / Q000032:analysis; D006352:Heart Ventricles / Q000737:chemistry / Q000378:metabolism; D000860:Hypoxia / Q000378:metabolism / Q000503:physiopathology*; D008222:Lymphokines / Q000032:analysis; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000503:physiopathology*; D009206:Myocardium / Q000737:chemistry / Q000378:metabolism; D016328:NF-kappa B / Q000032:analysis / Q000037:antagonists & inhibitors* / Q000378:metabolism; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D011759:Pyrrolidines / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013859:Thiocarbamates / Q000494:pharmacology*; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D000975:Antioxidants; D016228:Endothelial Growth Factors; D008222:Lymphokines; D016328:NF-kappa B; D011759:Pyrrolidines; D013859:Thiocarbamates; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; C020972:pyrrolidine dithiocarbamic acid