Expression of PDGF-beta receptor in broilers with pulmonary hypertension induced by cold temperature and its association with pulmonary vascular remodeling.
OBJECTIVE
The purpose of the present study was to characterize the relationship between platelet-derived growth factor beta receptor (PDGF-beta receptor) expression and pulmonary vascular remodeling found in broilers subjected to cold temperature beginning at 14 days of age.


METHODS
One hundred and sixty-one-day-old mixed-sex Avian-2000 commercial broilers were randomly divided into a normal temperature group (control) and a cold temperature group (cold). All the birds were brooded in normal temperature up to day 14, with the lighting schedule at 24 h per day. Starting at day 14, birds in the cold group were moved to a pen in the cold house and subjected to low temperature, while birds in the control group were still brooded at normal temperature. On days 14, 23, 30, 37 and 44, the right/total ventricle weight ratio (RV/TV), packed cell volume (PCV), the vessel wall area to vessel total area ratio (WA/TA), mean media thickness in pulmonary arterioles (mMTPA) and the expression of PDGF-beta receptor in pulmonary arterioles were measured, respectively. Cumulative pulmonary hypertension syndrome (PHS) morbidity was recorded in each group.


RESULTS
Cool ambient temperature increased PHS morbidity of broilers. The values of WA/TA and mMTPA were also increased significantly compared with control group. PCV values in the cold temperature group were elevated from days 30 to 44, and RV/TV ratios were increased on days 37 and 44. Cold exposure enhanced PDGF-beta receptor expression in pulmonary arterioles, and the PDGF-beta receptor expression was significantly correlated with pulmonary vascular remodeling that was dedicated by increased WA/TA and mMTPA.


CONCLUSIONS
The results indicated that PDGF-beta and its receptor were involved in the underlying mechanisms of pulmonary vascular remodeling in pulmonary hypertensive broilers.
Li
Jin-Chun
JC
Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls, Nanjing Agricultural University, Nanjing 210095, China.
Pan
Jia-Qiang
JQ
Huang
Guo-Qing
GQ
Tan
Xun
X
Sun
Wei-Dong
WD
Liu
Yan-Juan
YJ
Wang
Xiao-Long
XL
D000818:Animals; D002645:Chickens / Q000502:physiology*; D003080:Cold Temperature; D005786:Gene Expression Regulation / Q000502:physiology; D006976:Hypertension, Pulmonary / Q000473:pathology / Q000503:physiopathology / Q000662:veterinary*; D018919:Neovascularization, Physiologic / Q000502:physiology*; D011201:Poultry Diseases / Q000473:pathology / Q000503:physiopathology*; D011651:Pulmonary Artery / Q000473:pathology / Q000503:physiopathology; D011652:Pulmonary Circulation / Q000502:physiology; D020797:Receptor, Platelet-Derived Growth Factor beta / Q000096:biosynthesis*
D020797:Receptor, Platelet-Derived Growth Factor beta