Kininogen expression by rat vascular smooth muscle cells: stimulation by lipopolysaccharide and angiotensin II.
To identify the presence of a local kallikrein-kinin system in vascular wall, we have studied whether rat vascular smooth muscle cells (VSMC) express kininogen in vitro and in vivo. Western blots using anti-T-kininogen antibody revealed the presence of T-kininogen in conditioned medium of cultured VSMC. T-Kininogen secretion by VSMC was markedly enhanced by the addition of lipopolysaccharide (LPS), angiotensin II (AII) and phorbol 12-myristate 13-acetate (PMA) to the culture. Experiments using specific inhibitors for protein kinases and on the PMA-induced down-regulation of protein kinase C suggested that a protein kinase C-dependent or unidentified pathway is involved in AII or LPS action, respectively. The intravenous injection of LPS (0.5 mg/kg) resulted in an increase in T-kininogen mRNA levels in the vascular smooth muscle of rat aorta, peaking at 16 h. Polyacrylamide gel electrophoresis of cDNA products generated by reverse transcription-polymerase chain reaction (RT-PCR) from aortic mRNA using primers specific for either T- or low-molecular-weight kininogen revealed that rat vascular smooth muscle expressed T-kininogen gene but not low-molecular-weight kininogen gene, and that LPS exclusively stimulated T-kininogen expression. The mRNA for high-molecular-weight kininogen was undetectable in either aortic smooth muscle or cultured VSMC by means of RT-PCR analysis. RT-PCR using specific primers for rat tissue kallikrein genes showed that aortic smooth muscle expressed KLK1 (true kallikrein) mRNA, but not KLK10 (T-kininogenase) mRNA. These results demonstrated that rat VSMC are a source of T-kininogen but not of low-molecular-weight- or high-molecular-weight kininogen, in contrast to the expression of true kallikrein but not of T-kininogenase by these cells.
Okamoto
H
H
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Kobe Gakuin University, Ikawadani-cho, Nishi-ku, Kobe 651-2180, Japan. okamotoh@pharm.kobegakuin.ac.jp
Yayama
K
K
Shibata
H
H
Nagaoka
M
M
Takano
M
M
D000804:Angiotensin II / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000818:Animals; D001011:Aorta / Q000187:drug effects* / Q000378:metabolism; D015139:Blotting, Southern; D015153:Blotting, Western; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000032:analysis; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007610:Kallikreins / Q000096:biosynthesis / Q000235:genetics; D019679:Kininogen, High-Molecular-Weight / Q000235:genetics; D019728:Kininogen, Low-Molecular-Weight / Q000235:genetics; D007704:Kininogens / Q000096:biosynthesis* / Q000235:genetics; D008070:Lipopolysaccharides / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013755:Tetradecanoylphorbol Acetate
D017077:Culture Media, Conditioned; D004791:Enzyme Inhibitors; D019679:Kininogen, High-Molecular-Weight; D019728:Kininogen, Low-Molecular-Weight; D007704:Kininogens; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D000804:Angiotensin II; D007610:Kallikreins; D013755:Tetradecanoylphorbol Acetate