Role of RANTES in the change of blood-brain barrier permeability in rats with acute pancreatitis

Abstract

Objectiye To investigate the expression of regulated on activation, normal T-cell expressed and secreted (RANTES) and occluding in brain, and investigate the role of expression of RANTES in the change of blood-brain barrier permeability of rats with acute pancreatitis. Methods 49 Sprague-Dawley rats were randomly divided into 7 groups according to random number table, including sham-operated group (SO) , acute edematous pancreatitis (AEP) 3, 6 h group and acute necrotizing pancreatitis (ANP) 3, 6, 12 and 24 h group. AEP and ANP were induced by retrograde injection of 0. 5% and 5% sodium taurocholate, respectively. RT-PCR, Western blot, and immunohistochemistry methods were performed to assess the expression of RANTES and occludin mRNA and protein in brain tissue. Results The RANTES mRNA expressions in SO, AEP 3, 6 h, ANP 3, 6, 12, 24 h group were 0, 0, 0, 0.36±0.05, 0.47±0.04, 0.65±0.05, 0.83±0.07, respectively; The RANTES protein expressions were 0, 0, 0, 0.42±0. 03, 0. 57±0.04,0.78±0.08, 1.05±0.08, respectively; the values in ANP group were significantly lower than those in SO group and AEP group (P<0.01). The occludin mRNA expressions were 1.21±0.07,1.17±0.07, 1.15±0.08,0.84±0.07,0.77±0.05,0.64±0.09,0.56±0.09, respectively, the occludin protein expressions were 1.18 ±0.08, 1. 16 ±0. 10, 1. 11 ±0. 10, 0. 90 ±0. 03, 0. 65 0.57 ±0.05, 0.48 ±0.05, respectively, the values in ANP group were significantly lower than those in SO group and AEP group (P< 0.01). The expression of RANTES was positively related to the pancreatic pathologic score (r = 0. 936,P< 0. 001) ; the expression of occluding was negatively related to the pancreatic pathologic score (r = - 0. 943, P < 0.001). The expression of RANTES was negatively related to the expression of occluding (r = -0. 943, P <0. 001). Conclusions The expression of RANTES was progressively increased in the brain tissue in rats with ANP, while the expression of occluding was progressively decreased; RANTES may play an important role in the change of blood-brain barrier permeability via down-regulating the expression of occluding. Key words: Pancreatitis;  Blood-brain barrier;  RANTES;  occludin