Effects of the L- and N-type calcium channel blocker cilnidipine on growth of vascular smooth muscle cells from spontaneously hypertensive rats.
Cultured vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) show exaggerated growth compared with cells from Wistar-Kyoto (WKY) rats. Calcium antagonists have recently been reported to have an in vivo antiproliferative effect on hypertensive cardiovascular organs. We investigated the effects of the calcium antagonist cilnidipine that blocks both L- and N-type calcium channels on the growth of VSMC from SHR. Cilnidipine (1 and 10 microM) significantly inhibited basal DNA synthesis in VSMC from both rat strains; the inhibition was significantly larger in VSMC from SHR than in cells from WKY rats, and was significantly greater than effects of nifedipine. Cilnidipine (1 microM) significantly inhibited serum-stimulated DNA synthesis in VSMC from both rat strains. The inhibition was more marked in VSMC from SHR than in cells from WKY rats. Angiotensin II, platelet-derived growth factor (PDGF)-AA, and phorbol-12-myristate-13-acetate dose-dependently increased DNA synthesis in VSMC from SHR but not in cells from WKY rats. Cilnidipine (1 microM) significantly suppressed this increase in DNA synthesis in VSMC from SHR. Expression of basic fibroblast growth factor (bFGF), transforming growth factor-beta1, and PDGF A-chain mRNAs was markedly greater in VSMC from SHR than in cells from WKY rats. Cilnidipine (1 microM) significantly inhibited the expression of TGF-beta1 mRNA in VSMC from SHR but not in cells from WKY rats. These findings suggest that cilnidipine exerts its antiproliferative effects through the inhibition of DNA synthesis induced by growth-promoting factors and by inhibiting the expression of TGF-beta1 mRNA in VSMC from SHR.
Hu
W Y
WY
Second Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan.
Fukuda
N
N
Su
J Z
JZ
Kanmatsuse
K
K
D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology* / Q000633:toxicity; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free; D004247:DNA / Q000096:biosynthesis; D004095:Dihydropyridines / Q000494:pharmacology* / Q000633:toxicity; D016222:Fibroblast Growth Factor 2 / Q000235:genetics / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D009543:Nifedipine / Q000494:pharmacology; D010982:Platelet-Derived Growth Factor / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism; D053773:Transforming Growth Factor beta1
D002121:Calcium Channel Blockers; D016895:Culture Media, Serum-Free; D004095:Dihydropyridines; D010982:Platelet-Derived Growth Factor; C508962:Tgfb1 protein, rat; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; C075278:platelet-derived growth factor A; D016222:Fibroblast Growth Factor 2; D004247:DNA; C065927:cilnidipine; D009543:Nifedipine; D013755:Tetradecanoylphorbol Acetate