L-arginine prevents reduced expression of endothelial nitric oxide synthase (NOS) in pulmonary arterioles of broilers exposed to cool temperatures.
This study investigated nitric oxide synthase (NOS) expression in the endothelium of pulmonary arterioles of broilers during the development of pulmonary hypertension syndrome (PHS). PHS was triggered by exposing broilers to sub-thermoneutral (cool) temperatures and an additional 1.0% L-arginine was added to the basal diet to evaluate the effects of supplemental L-arginine on nitric oxide (NO) production, endothelial NOS expression, and the incidence of PHS. Cumulative mortality from PHS, right/total ventricle weight ratios (RV/TV), and body weights were recorded. Plasma NO concentration and NOS expression in the endothelium of pulmonary arterioles with an outer diameter ranging from 100 to 200 microm were determined. Birds exposed to cool temperatures had increased pulmonary hypertension and PHS mortality and diminished endothelial NOS expression. Supplemental dietary L-arginine reduced PHS mortality and elicited higher NOS expression within the pulmonary endothelium coincident with elevated NO production. The results demonstrated that broilers developing PHS exhibited diminished NOS expression in the endothelium of their pulmonary arterioles. Supplemental L-arginine prevented the reduced expression of NOS in the pulmonary endothelium, which might contribute to the increased production of NO by the pulmonary vasculature.
Tan
Xun
X
Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls, Nanjing Agricultural University, Nanjing 210095, PR China.
Sun
Wei-Dong
WD
Li
Jin-Chun
JC
Pan
Jia-Qiang
JQ
Liu
Yan-Juan
YJ
Wang
Jin-Yong
JY
Wang
Xiao-Long
XL
D000818:Animals; D001120:Arginine / Q000494:pharmacology*; D001160:Arterioles / Q000378:metabolism*; D002645:Chickens / Q000378:metabolism*; D003080:Cold Temperature; D005786:Gene Expression Regulation; D009569:Nitric Oxide / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism*
D009569:Nitric Oxide; D001120:Arginine; D052250:Nitric Oxide Synthase Type III