ABSTRACT
Objective To investigate the effects of B-type natriuretic peptides (BNP) on expression of monocyte chemoattractant protein-1(MCP-1) in rat peritoneal macrophages and to identify the inflammation-mediated effects of BNP in macrophages. Methods Peritoneal macrophages of primary culture were treated with BNP, BNP+HS-142-1, or BNP+TNF-?+HS-142-1. The protein expression of MCP-1 was measured by Western blot. Results BNP enhanced the MCP-1 protein expression in macrophages, and this effect could be abrogated by HS-142-1. In addition, BNP could inhibit TNF-? induced MCP-1 expression. Conclusion BNP can induce the MCP-1 protein expression in macrophages, suggesting BNP has a pro-inflammatory effect. However, BNP also can inhibit TNF-? induced MCP-1. These findings suggest that the effect of inflammation-mediated by BNP is biphasic though the mechanism is still unclear.