RESUMEN
Objective To investigate the role of expression of tall-like receptor 4 (TLR4) on medullary system cell (neutrophii, platelet) and endothelial cell surface in polymorphonuclear neutrophils (PMN) recruitment in rata with acute necrotizing pancreatitis. Methods C3H/He-J mice and C3H/He-N mice were divided into 4 groups by bone marrow transplantation: mosaic of medullary system cell TLR4-/- and endothelial cell TLR4 +/+ ; mosaic of medullary system cell TLR4 +/+ and endothelial cell TLR4-/-; mosaic of medullary system cell TLR4 +/+ and endothelial cell TLR4 -/-; mosaic of medullary system cell TLR4-/- and endothelial cell TLR4-/-, another control group was also established. ANP was induced in all these groups by intraperitoneal injection of cerulein and caudal vein injection of lipopolysaccharide. Serum amylase, pancreatic tissue naphthol AS-D chloroacetate esterase, MPO activity, TRL4 mRNA expression in peripheral blood granuloeyte was determined by RT-PCR, TRL4 protein expression in pancreatic tissue was measured by immunohistochemisty. Results Compared with that of control group, the levels of serum amylase in the 4 groups all significantly elevated and there was no difference among these 4 groups. Pathological scores of pancreas in the 4 groups were 5.52 ± 1.21, 5.18 ± 1.02, 2.03 ± 0. 82, 1.92 ± 0. 78, respectively; MPO activities were (1.834 ± 0. 170) U/g, (2. 596 ±0. 138) U/g, (0. 367 ±0. 018) U/g, (0. 202 ±0. 018) U/G, respectively; AS-D counts were 66.88 ± 2.17, 75.00 ± 2.43, 21.50 ± 2.38, 20.00 ± 2.19, respectively ; the expressions of TLR4mRNA of granular cell in peripheral blood were 0. 037 ± 1. 047 E-2, 1. 489 ± 8. 084 E-2, 1.470 ± 5. 210E-2, 0. 017 ± 6. 668 E-3, respectively; the 2 groups with endothelial eel1 TLR4 +/+ had strongly positive expression of TLR4 protein in vascular endothelial cell ; while the 2 groups with endothelial cell TLR4-/- had no expression; the pancreatic injuries, MPO activities, AS-D counts and TLR4 protein in the 2 groups with endothelial cell TLR4 +/+ were significantly higher than those in the 2 groups with endothelial cell TLR4-/-. Conclusions It was endothelial cell, not peripheral blood granulocyte, which played a key role in the process of neutrophil recruitment and pathological injure of ANP.
RESUMEN
Objective To investigate the significance of expression of toll-like receptor on medullary system cell and endothelial cell surface in PMN recruiting in severe acute pancreatitis.Method In this study,26 C3H/He-J mice and 26 C3H/He-N mice were derided into 4 groups by bone marrow transplantation:group A, mosaic of medullary system cell TLR4-/- and endothelial cell TLR4+/+,group B, mosaic of medullary system cell TLR4+/+ and endothelial cell TLR4-/- ;group C, homozygote ofTLR4+/+ ;group D, homozygote of TLR4-/-. SAP was induced to all these mice. Amylase, TRIA of granular cell in peripheral blood,TRL4 expression in pancreas, Naphthol AS-D chloroacetate esterase, MPO activity were tested. Results Amylase level increased in all mice, there was no differences of the amylase level among groups, TRIA of granular cell in peripheral blood in group B and C was significant higher than A and D(P<0.05), TLR4 in pancreas were positive in group A and C, negative in group B and D, AS-D count and M PO activity in group A and C were higher than that in group B and D (P < 0. 05 ). Conclusions It was endothelial cell, not peripheral blood granulocyte, that plays a key role in recuiting neutrophils that triggers severe acute pancreatitis.