To investigate the effect of sea anemone toxin anthopleurin-Q (AP-Q) on potassium currents in isolated rats and guinea pig ventricular myocytes.Methods The ventricular cells of guinea pigs and SD rats were obtained by enzymatic dissociation method.Whole cell patch clamp technique was used to record potassium currents (Ito,IK,and IK1).Results AP-Q 3-100 nmol/L increased Ito in a concentration-dependent manner,with an EC50 value of 12.7 nmol/L.At a potential of +50mV,AP-Q 10nmol/L increased Ito from (13.3±3.4) pA pF-1 to (19.46±4.3) pA pF-1.AP-Q 0.1-100 nmol/L increased IK and IK tail in a concentration-dependent manner with EC50 values of 4.7 nmol/L and 5.0 nmol/L,respectively.AP-Q 1 pmol/L-100 nmol/L increased IK1 in dose-dependent manner,with an EC50 of 0.2 nmol/L.Conclusions The effect of AP-Q on Ito,IK and IK1 may partly explain its mechanism in shortening APD and increasing RP.(J Geriatr Cardiol 2008;5:243-247)

OBJECTIVETo evaluate the relationship between uric acid (UA) and peripheral arterial disease (PAD) in Chinese patients with coronary heart disease (CHD).

METHODSUA levels and PAD were evaluated in 3251 Chinese hospitalized patients with CHD (age > or = 50 years). PAD was diagnosed when the ankle-brachial index was < 0.9 but patients with an ankle-brachial index of > 1.4 were excluded because of false negative rate. Potential confounding variables with P < 0.10 were adjusted for multivariate analysis.

RESULTSIn univariate analysis, UA levels were higher in patients with PAD than in those without PAD (349.80 micromol/L +/- 128.45 micromol/L vs. 323.00 micromol/L +/- 110.72 micromol/L, P < 0.001). Rate of hyperuricemia in patients with PAD and without PAD were 31.62% and 22.48% (P < 0.001) respectively. Prevalence rates of PAD for quintiles of UA level were 23.2%, 27.4%, 36.1%, 43.2% and 72.7%, respectively (P-trend < 0.05). With UA level as a continuous variable, the multivariate-adjusted odds ratio for PAD was 1.002 (95% confidence interval: 1.001 - 1.002) (P < 0.001). The optimal cut-off point for UA as determined by the receiver operating characteristic curve, was 227.2 micromol/L. The sensitivity and specificity at this cut-off point were 84.6% and 20.3%, respectively. The area under curve was 0.521 (95% confidence interval: 0.504 - 0.547) and the multivariate-adjusted odds ratio for PAD for UA above this level was 1.292 (95% confidence interval: 1.047 - 1.596) (P < 0.01). The results, however, after exclusion those cases who used diuretics, were similar.

CONCLUSIONElevated uric acid level seemed a significant and independent risk factor for PAD in Chinese hospitalized patients with CHD (age > or = 50 years).

Analysis of Variance ; Ankle Brachial Index ; China ; Coronary Disease ; blood ; complications ; Humans ; Hyperuricemia ; complications ; Middle Aged ; Odds Ratio ; Peripheral Vascular Diseases ; etiology ; Prevalence ; ROC Curve ; Risk Factors ; Sensitivity and Specificity ; Uric Acid ; blood

OBJECTIVETo evaluate the risk factors for peripheral arterial disease (PAD) and the relationship of low ankle brachial index (ABI) to all-cause and cardiovascular disease (CVD) mortality in Chinese male patients with hypertension.

METHODSThe data of 1606 male participants with hypertension from the eight hospitals in Beijing and Shanghai were analyzed. ABI was ascertained at baseline by measuring the systolic pressures on bilateral brachial and tibial arteries. ABI < or = 0.9 was used as the diagnostic criteria for PAD identification. The follow-up survey was conducted from November 2005 to January 2006.

RESULTSOf 1606 male participants with hypertension at baseline, 406 (25.3% ) were in low-ABI group and 1200 (74.7%) were in normal-ABI group. Older age, TC, history of diabetes, history of smoking and 2-grade hypertension were associated with low ABI in male patients with hypertension. During the (12.87 +/- 2.94) months follow-up, there were 153 deaths. Of which, 62 were attributable to CVD. Low ABI was associated with adjusted all-cause and CVD mortality risk of 1.728 (1.223-2.441) and 2.388 (1.409-4.046) respectively in Cox regression models. Rate of survival for the low-ABI group was significantly worse than for the normal-ABI group. The risk of all-cause and CVD mortality was increased with the decline of ABI.

CONCLUSIONLow ABI is independently associated with the high risks of all-cause and CVD mortality in Chinese male patients with hypertension. The utility of ABI as a tool for predicting mortality in the patients with hypertension should be popularized.

Ankle Brachial Index ; Cardiovascular Diseases ; mortality ; China ; Follow-Up Studies ; Humans ; Hypertension ; epidemiology ; etiology ; Male ; Risk Factors