The effects of hydroxysafflor yellow A on blood pressure and cardiac function.

This work aims to investigate the effects of HSYA on cardiac function and blood pressure. To evaluate changes in mean arterial pressure (MAP) and heart rate (HR), different groups of pentobarbitone-anesthetized normotensive and spontaneously hypertensive rats (SHR) were treated with intravenous HSYA (0.1-3 mg/kg). Isolated WKY rat hearts in Langendorff system were employed for examining the effect of HSYA on hemodynamic. After 30 min equilibration time the isolated hearts were perfused with HSYA (30 μmol/L) in a stepwise fashion. Potassium channel inhibitors were used to determine the role of potassium channel activation in HSYA effect. Intravenous injection of the HSYA significantly reduced MAP and HR in both normotensive rats and SHR in a dose-dependent manner. HSYA reduced left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), the maximum rate of increase of left ventricular pressure (+dp/dt(max)) and heart rate (HR) in a dose-dependent manner. HSYA had no remarkable effect on the maximum rate of decrease of left ventricular pressure (-dp/dt(max)); BK(Ca) and K(ATP) blocker can weakened the inhibitory effect of HSYA on heart function and HR, but K(V) and K(ACh) blocker did not significantly weaken the HSYA effects. Our results show that HSYA could significantly reduce blood pressure and heart rate, which may be related to activation of BK(Ca) and K(ATP) channels.

Nie PH ，Zhang L ，Zhang WH ，Rong WF ，Zhi JM ... -  《-》

Neuroprotective effects of hydroxysafflor yellow A: in vivo and in vitro studies.

Zhu H ，Wang Z ，Ma C ，Tian J ，Fu F ，Li C ，Guo D ，Roeder E ，Liu K ... -  《PLANTA MEDICA》

Hydroxysafflor yellow A actives BK(Ca) channels and inhibits L-type Ca channels to induce vascular relaxation.

Hydroxy-safflor yellow A (HSYA) can exert a variety of effects upon the vascular system. However, the underlying mechanisms are not clear. The present study is to investigate its vasodilating effect and the mechanisms. Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR) were enrolled for studying effects of HSYA on blood pressure, vasodilation, intracellular Ca2+ transient and membrane ion channels. Vasodilation and intracellular Ca2+ transient were measured by using vasomotor assay and fluorescence imaging system, respectively. The effect of HSYA on the large conductance Ca2+ activated and voltage-gated potassium channel (BKCa channel) currents in rat mesentery artery and on L-type calcium channel (Ca-L) currents in HEK293cells expressed with Ca-L were investigated using patch clamp techniques. Blood pressure of SHR and WKY rats were concentration dependently reduced by HSYA with a larger effect of HSYA in SHR than that in WKY rats. The tension of mesenteric arteries induced by 3 μM phenylephrine was attenuated by HSYA (IC50 = 90.8 μΜ). Patch clamp study showed that HSYA could activate BKCa channels and suppress Ca-L channels in a concentration dependent manner. The results of calcium signaling assays indicated that HSYA could reduce the intracellular free Ca2+ level. These findings demonstrate that HSYA could activate BKCa channels and inhibit Ca-L channels and reduce intracellular free Ca2+ level, which are probably important for its vasodilatory effect.

Wang N ，He D ，Zhou Y ，Wen J ，Liu X ，Li P ，Yang Y ，Cheng J ... -  《-》

Evidence that hydroxysafflor yellow A protects the heart against ischaemia-reperfusion injury by inhibiting mitochondrial permeability transition pore opening.

Liu YN ，Zhou ZM ，Chen P 《-》

[Effects of losartan, ramipril and their combination on left ventricular remodeling and function in spontaneous hypertensive rats].

Xu R ，Zhang Y ，Zhang M ，Li XC ，Cai H ，Chen WQ ，Zhu H ，Ge ZM ，Zhang W ... -  《-》