OBJECTIVETo study the effect of taurine on apoptosis in PASMCs, and whether the death-receptor pathway act in the mechanism.

METHODCulture the PASMCs, and divided the cells into control, SD. Acridine orange(AO) assay and western-blot analysis on the expression of Bax, Bcl-2, Procaspase-3 and Fas were used to study the mechanism.

RESULTA major finding of this study is that the Tau effects many apoptosis index, such as increasing the expression of Bax and Fas, decreasing the expression of Procaspase-3, and Bcl-2, accrescencing the mitochondrial depolarization, causing the nuclear shrinkage, all these datas demonstrated that Tau induced the apoptosis in pulmonary artery smooth muscle cells through mitochondrial-dependent pathway.

CONCLUSIONTau induces the apoptosis in pulmonary artery smooth muscle cells through death-receptor.

Animals ; Apoptosis ; drug effects ; Male ; Muscle, Smooth, Vascular ; cytology ; drug effects ; Myocytes, Smooth Muscle ; drug effects ; Pulmonary Artery ; cytology ; drug effects ; Rats ; Rats, Wistar ; Taurine ; pharmacology

AIMTo investigate the impact of human urotensin II (hUII) on pulmonary arterial smooth muscle cell (PASMCs) cycle in vitro.

METHODSPASMCs dissected from Wistar rats were cultured in vitro, and incubated with series of concentrations of hUII (10(-7) mol/L, 10(-8) mol/L, 10(-9) mol/L) for 12 hours under normoxia or hypoxia condition, in order to analyze cell cycle progression and sub-G1 of PASMCs by using flow cytometric analysis stain of propidium iodide, which represented the proliferative and apoptotic changes in PASMCs.

RESULTSThe study showed a dose-dependent effect of hUII on PASMCs proliferation, which reflected the increase both in percentage of S phase of cell cycle and proliferative index (PI). The response of PASMCs to hUII was different under normoxic and hypoxic conditions. Compared with the control group, the treatment of 10(-7) mol/L, 10(-8) mol/L and 10(-9) mol/L hUII produced an increase of 175%, 136% and 118% under normoxia, respectively, and 135%, 118% and 103% under hypoxia, respectively. The concentration 10(-7) mol/L hUII played a significant role in PASMCs proliferation both under hypoxia and normoxia (P < 0.01). The results of cell cycle did not show sub-G1 of PASMCs at various concentrations of hUII.

CONCLUSIONhUII may stimulate DNA synthesis in S phase cell cycle of PASMCs and the proliferation of PASMCs under normoxia and hypoxia conditions, which promote cell growth in a dose-dependent manner.

Animals ; Cell Cycle ; drug effects ; Cells, Cultured ; Humans ; Male ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; Pulmonary Artery ; cytology ; Rats ; Rats, Wistar ; Urotensins ; pharmacology

AIMTo investigate the effect of fractalkine on cell proliferation of cultured rat pulmonary artery smooth muscle cells (PASMCs) in vitro.

METHODSRat PASMCs were cultured in vitro, and treated with different concentrations (10(-10), 10(-9), 10(-8) mol/L) of fractalkine for 12 h, 24 h and 48 h. The cell proliferation was quantified by MTT assay. The cell cycle of PASMCs was measured by flow cytometric(FCM) analysis.

RESULTSMTT assay showed that fractalkine promoted significantly the proliferation of PASMCs, and the effect was concentration-dependent. FCM analysis indicated that fractalkine increased the percentage of S phase and proliferative index (PI). The percentage of S phase and PI of PASMCs were increased after treated with fractalkine for 12 hours, which reached a maximal level at 24 hours.

CONCLUSIONFractalkine promotes rat PASMCs proliferation in a concentration-dependent manner.

Animals ; Cell Proliferation ; drug effects ; Cells, Cultured ; Chemokine CX3CL1 ; pharmacology ; Male ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; Pulmonary Artery ; cytology ; Rats ; Rats, Sprague-Dawley

The aim of this study was to elucidate the effects of anti-hypertensive drugs, nifedipine, furosemide, hydrochlorothiazide, captopril, and atenolol on DNA synthesis and proliferation of cultured rat aortic smooth muscle cells induced by fetal calf serum. Aortic smooth muscle cells from Sprague-Dawley rats were isolated, cultured, and seeded in multi-well plates. When confluent, cells were cultured in a conditioned medium without fetal calf serum. After 72 hours, cells were cultured in the medium retaining 10% fetal calf serum with or without anti-hypertensive drugs by increasing the concentration between 10(-8) and 10(-4) M. DNA synthesis was assessed by [3H]-thymidine uptake and proliferation by cell numbers using a hemocytometer. Nifedipine at a concentration of 10(-5) M and 5 x 10(-5) M inhibited serum-induced DNA synthesis significantly by 50.8% and 86.6%, respectively (p < 0.05). The results of cell numbers paralleled those of 3H-thymidine incorporation. Serum-induced DNA synthesis was also reduced by 32.6% at the highest dose of furosemide (10(-4) M), but there was no statistical significance. Hydrochlorothiazide, captopril, and atenolol did not show anti-proliferative effect throughout any of the doses. In conclusion, among the various anti-hypertensive drugs, nifedipine seems to be most beneficial in view of its direct inhibitory effect on DNA synthesis and proliferation of smooth muscle cells, as well as for its anti-hypertensive effect.
Animal ; Antihypertensive Agents/pharmacology* ; Aorta/metabolism* ; Aorta/drug effects* ; Cell Division/drug effects ; Cells, Cultured ; DNA/biosynthesis* ; Male ; Muscle, Smooth, Vascular/metabolism* ; Muscle, Smooth, Vascular/drug effects* ; Muscle, Smooth, Vascular/cytology ; Rats ; Rats, Sprague-Dawley

Benzimidazoles ; pharmacology ; Benzoates ; pharmacology ; Cell Proliferation ; drug effects ; Humans ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; Tetrazoles ; pharmacology ; Valine ; analogs & derivatives

Animals ; Cell Proliferation ; drug effects ; Female ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; Nitric Oxide ; metabolism ; Rats ; Rats, Sprague-Dawley ; Tamoxifen ; analogs & derivatives ; pharmacology

OBJECTIVETo study the action mechanism of tetramethylpyrazine (TMP) on the proliferation of vascular smooth muscle cells (VSMCs), thus providing experimental evidence for Chinese medicine to effectively prevent restenosis.

METHODSRats' thoracic aorta VSMCs in vitro cultured (cell line A7r5) were divided into five groups, i.e., the negative control group, the angiotensin II (Ang II, 10(-6) mol/L) group, the low dose TMP (20 micromol/L) plus Ang II group, the middle dose TMP (40 micromol/L) plus Ang II group, the high dose TMP (80 micromol/L) plus Ang II group. The proliferation ratio was detected by MTT. Gene and protein expressions of Wnt4, Dvl-1, beta-catenin, CyclinD1, and collagen I and III were detected with real-time fluorescent quantitative PCR and Western blot respectively.

RESULTSCompared with the negative control group, the proliferation ratio of VSMCs obviously increased in the Ang II group (P < 0.05). Compared with the Ang II group, the proliferation ratio of VSMCs obviously decreased in the middle dose TMP plus Ang II group and the high dose TMP plus Ang II group (P < 0.05). Compared with the negative control group, gene and protein expressions of Wnt4, Dvl-1, beta-catenin, CyclinD1, Col I, and Col III were obviously up-regulated in the Ang II group (P < 0.05). Compared with the Ang II group, mRNA and protein expressions of Wnt4, Dvl-1, beta-catenin, CyclinD1, Col I, and Col III were obviously down-regulated in the middle dose TMP plus Ang II group and the high dose TMP plus Ang II group (P < 0.05). The aforesaid indices were dose-dependent in the low, middle, and high dose TMP plus Ang II groups.

CONCLUSIONTMP inhibited Ang II induced proliferation and collagen secretion of VSMCs through down-regulating Wnt signal pathway.

Animals ; Cell Proliferation ; drug effects ; Cells, Cultured ; Collagen ; biosynthesis ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; metabolism ; Pyrazines ; pharmacology ; RNA, Messenger ; genetics ; Rats

AIMAccumulated evidence suggest that the development of vascular calcification is similar to osteogenesis. Here we want to elucidate the effect of the common used osteo-regulatory factor 1,25(OH)2D3 on vascular calcification.

METHODS AND RESULTSAdding 10(-9) mol/L to the culture media 1,25(OH)2D3 time dependently increased the calcium deposition on the in vitro calcification of bovine vascular smooth muscle cells (BVSMCs) induced by beta-GP. It also increased cellular alkaline phosphatase activity by 301.1% during the calcified process. Osteocalcin, one of the osteogenic specific metric proteins, was dramatically elevated by 58.3% during the calcified processes, which indicate the transformation of BVSMCs to osteoblastic cell. 1,25(OH)2D3 had no such effect on non-calcified BVSMCs.

CONCLUSIONThese data suggest that 1,25(OH)2D3 exerts a stimulatory effect on vascular calcification through increasing the synthesis of ALP. This effect shares the same character as osteoblast cells. This effect is limited to the calcified prone vascular cell.

Animals ; Calcitriol ; metabolism ; Cattle ; Cells, Cultured ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; drug effects ; metabolism ; pathology ; Osteocalcin ; metabolism ; Vascular Calcification ; metabolism ; pathology ; Vitamin D ; analogs & derivatives ; pharmacology

AIMTo study the effects of oxyphenamone (Oxy) on activation of Ca(2+)-activated K+ channels in rabbit mesenteric vascular smooth muscle cells.

METHODSTo measure the effect of Oxy on the Ca(2+)-activated K+ channel (BK (Ca) channel) activity in rabbit mesenteric vascular smooth muscle cells by using whole cell patch clamp techniques.

RESULTSOxy reversibly increase BK (Ca) channel activity in rabbit mesenteric artery smooth muscle cells. Application of Oxy (0.1 mumol.L-1) to the perfusion solution caused significant increase in outward currents and its effect was completely abolished by washout; The outward currents K+ was inhibited by TEA (7.5 mmol.L-1); Oxy activated the BK (Ca) channel in a dose-dependent manner (0.01-10 mumol.L-1).

CONCLUSIONOxy directly increase the activity of BK (Ca) channel activity in rabbit mesenteric vascular smooth muscle cells in dose-dependent manner.

Animals ; Cardiotonic Agents ; pharmacology ; Mesenteric Arteries ; cytology ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; physiology ; Organic Chemicals ; Patch-Clamp Techniques ; Potassium Channels, Calcium-Activated ; drug effects ; Rabbits

Animals ; Cells, Cultured ; Interleukin-1 ; pharmacology ; Matrix Metalloproteinase 1 ; secretion ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; metabolism ; Platelet-Derived Growth Factor ; pharmacology ; Rabbits