Experimental study of Duffy antigen receptor for chemokines in tissue and the inflammatory reaction of limb with venous hypertension

OBJECTIVE: To explore the role and mechanism of Duffy antigen receptor for chemokines (DARC) of tissue in promoting the inflammatory reaction of the limb with venous hypertension. METHODS: moral arteriovenous fistula was surgically created to establish the rat model of venous hypertension. A total of 36 SD rats were randomly divided into pcDNA3.1-DARC (Group A), empty plasmid of pcDNA3.1 (Group B) and control (Group C) groups. The animals were sacrificed at Days 14 and 42 post-operation respectively. The expressions of DARC at the RNA and protein level were detected by real-time polymerase chain reaction (PCR) and Western blot. And the serum level of interleukin (IL)-8 was detected by enzyme linked immunosorbent assay (ELISA) and the degrees of apoptosis and leukocytic infiltration of local tissue were detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) and hematoxylin and eosin (HE) staining. RESULTS: With the elapsing time of venous hypertension, the DARC expression in tissue, the extent of apoptosis and leukocytic infiltration in tissue showed an increasing trend in Groups A and B. Group A was obviously higher than Group B during the corresponding period. And the differences were statistically significant (P < 0.05). The serum levels of IL-8 of Groups A and B showed a decreasing trend. And Group A was obviously lower than Group B. Both groups were higher than the control group. The differences were statistically significant (P < 0.05). CONCLUSIONS: The level of DARC in tissue and the degree of inflammatory reaction of venous hypertension have a positive correlation. And DARC may promote the development of venous hypertension inflammation through augmenting the adhesion and migration of leukocytes.