Induction of angiogenesis in NO-deficient rat heart.
Angiogenesis is known to be triggered by various stimuli including hypertension. It was previously found that NO-deficient hypertension is accompanied by structural remodeling of the cardiac muscle and large coronary arteries. This study was aimed to examine the qualitative subcellular alterations of capillaries in the heart of the rats treated with L-NAME (40 mg/kg/day for 4 weeks). The results showed that long-lasting inhibition of NO production induced an apparent activation of fibroblast function. This was associated with enhancement of fibrotization as well as with the induction of angiogenesis. Accordingly, fibroblasts were frequently located in the vicinity of capillary pericytes, which was followed by their detachment and migration. Moreover, besides inactive or even injured capillaries, the other ones exhibited extensive proteosynthetic activity linked to capillary growth, proliferation and migration of endothelial cells. The results strongly indicate enhanced triggering of the angiogenesis in L-NAME-induced NO-deficient hypertension.
Okruhlicová
L
L
Institute for Heart Research, Slovak Academy of Sciences, Bratislava, Slovak Republic. usrdokru@savba.sk
Tribulová
N
N
Bernátová
I
I
Pechánová
O
O
D000818:Animals; D002196:Capillaries / Q000648:ultrastructure; D003331:Coronary Vessels / Q000648:ultrastructure*; D004730:Endothelium, Vascular / Q000648:ultrastructure; D004791:Enzyme Inhibitors / Q000008:administration & dosage*; D005347:Fibroblasts / Q000648:ultrastructure; D006352:Heart Ventricles / Q000648:ultrastructure; D006973:Hypertension / Q000139:chemically induced / Q000473:pathology; D008297:Male; D008854:Microscopy, Electron; D009206:Myocardium / Q000648:ultrastructure*; D019331:NG-Nitroarginine Methyl Ester / Q000008:administration & dosage; D009389:Neovascularization, Pathologic / Q000209:etiology* / Q000473:pathology; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D051381:Rats; D017208:Rats, Wistar
D004791:Enzyme Inhibitors; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester