Reduced PKCalpha expression in pulmonary arterioles of broiler chickens is associated with early feed restriction

OBJECTIVE: The present study was conducted to investigate the effect of early feed restriction on protein kinase Calpha (PKCalpha) expression in pulmonary arterioles, which has been revealed to promote pulmonary vascular remodeling in pulmonary hypertensive broilers. METHODS: A total of 270day-old mixed sex commercial broilers were randomly distributed to a normal temperature control group (NT), a low temperature control group (LT) and a low temperature plus feed restriction group (LR). The PHS incidence, the right/total ventricular weight ratio (RV/TV), the vessel wall area/vessel total area ratio (WA/TA), the mean media thickness in pulmonary arterioles (mMTPA) and the expression of PKCalpha in the pulmonary arterioles were measured weekly. RESULTS: Low temperature treatment significantly increased the PHS mortality. The RV/TV, WA/TA and mMTPA values of group LT were significantly elevated compared with those of group NT on d 35 and 42. The LT chickens had increased PKCalpha expression compared with their NT counterparts on d 28 and afterwards. Feed restriction reduced the PHS mortality, RV/TV, WA/TA and mMTPA in cold-exposed broilers. The LR chickens had much lower PKCalpha expression in pulmonary arterioles than the LT chickens. CONCLUSION: Early time feed restriction inhibited pulmonary vascular remodeling in broilers, which might be partly attributed to reduced PKCalpha expression in pulmonary arterioles.