[The effects of L-arginine and nimodipine on the expression of monocyte chemoattractant protein-1 in endothelial cells induced by lipopolysaccharide].
OBJECTIVE
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).


METHODS
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.


RESULTS
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.


CONCLUSIONS
L-arginine and nimodipine can markedly inhibit the expression of MCP-1 in ECs induced by LPS.
Yu
G
G
Department of Pathology, Tongji Medical University, Wuhan 430030.
Deng
Z
Z
D000818:Animals; D001013:Aorta, Thoracic / Q000166:cytology; D001120:Arginine / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002417:Cattle; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000096:biosynthesis* / Q000235:genetics; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D009553:Nimodipine / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics
D002121:Calcium Channel Blockers; D018932:Chemokine CCL2; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D009553:Nimodipine; D001120:Arginine