The effects of L-arginine and nimodipine on the expression of monocyte chemoattractant protein-1 in endothelial cells induced by lipopolysaccharide
Yu, G.; Deng, Z.
Zhonghua Yi Xue Za Zhi 79(9): 699-701
1999
ISSN/ISBN: 0376-2491 PMID: 11715462 Document Number: 499860
To examine the effects of L-arginine and nimodipine on the expression of monocyte chemoattractant protein-1 (MCP-1) mRNA and protein induced by lipopolysaccharide (LPS) in endothelial cells (ECs). After 8-hour exposure to LPS, LPS + L-arginine and LPS + nimodipine respectively, the total RNA in ECs was extracted by the guanidinium isothiocyanate method. The MCP-1 mRNA expression in ECs was examined by Dot blot analysis using a gamma-32P-end-labeled 35 mer oligonucleotide probe of MCP-1. MCP-1 protein in the EC-conditioned media (EC-CM) was determined by sandwich ELISA for each group. The expression of MCP-1 protein in ECs was examined immunocytochemically. Dot blotting showed that after exposure to LPS, the integral absorbance (A) value of the dots of MCP-1 mRNA on the nitrocellulose membrane were 3.14, which was 2.5-fold as much as that in the control group (A = 1.24). The A values of the LPS + L-arginine group and the LPS + nimodipine group were 1.43 and 1.65, respectively. ELISA showed that the MCP-1 protein content in the EC-CM of the LPS group was 6.29 +/- 0.53 ng/ml, which was markedly higher than that of the control group (2.32 +/- 0.16) ng/ml (P < 0.01). The MCP-1 protein content in the EC-CM of the LPS + L-arginine group and the LPS + nimodipine group was significantly lower than that of the LPS group (P < 0.01). Furthermore, the ECs in LPS group showed a strong immunoreactivity for the polyclonal MCP-1 antibody, whereas the ECs in control, L-arginine and nimodipine groups revealed a weak postive immunostaining. L-arginine and nimodipine can markedly inhibit the expression of MCP-1 in ECs induced by LPS.