RESUMEN
Objective: To explore the possible mechanism of statins improving endothelial function via observing the effect of a high single dose atorvastatin on endothelial dysfunction and peripheral blood leucocyte Rho kinase activity in patients with unstable angina (UA). Methods: A total of 78 consecutive UA patients admitted in our hospital from 2012-08 to 2014-02 were enrolled. The patients received a single dose of atorvastatin 80 mg on the day of admission. Flow-mediated vasodilation (FMD) of brachial artery was examined by high-resolution ultrasound at before and 12 hours after medication. Protein expression of phospho-speciifc Thr853-MYPT1 (p-MYPT1Thr853) and MYPT1 was measured by Western blot analysis; peripheral blood leukocyte Rho kinase activity was assayed by the proportion of phospho-Thr853 in myosin binding subunit of light chain phosphatase (MYPT1). Results: Compared to prior medication, with atorvastatin 80 mg for 12 hours, FMD was increased 28.15% as (6.50 ±1.68) % vs (8.33 ± 1.93) %,P<0.001 and peripheral blood leucocyte Rho kinase activity was decreased 32.78% as (58.91 ± 5.22) % vs (39.6 ± 3.85 ) %,P=0.002. Conclusion: High dose atorvastatin could rapidly improve vascular endothelial dysfunction in UA patients. inhibiting of RhoA/Rho kinase pathway may involve in the effect of statins improving endothelial function.
RESUMEN
Objective To observe the effects of the chronic adventitia injury on the vasoconstriction of the rat carotid artery. Methods A non-occlusive silicone collar was positioned around the right carotid artery of rats. Blood flow and vascular reactivity to 5-HT were examined, and both carotids were harvested for morphometry at day 3,7 and 14 after operation. Results In the early stage of advenfitia injury induced by positioning a silicone collar around file rat carotid artery, there appeared the characteristic histological changes of chronic vasospasm in collared artery, such as the reduction of the luminal area for （12.15±2.29）% at day 3 after operation （P =0.003 ） and （45.17±3.84）% at day 7 （P 〈 0.001 ）] ,corrugation of the internal elastic lamina,medial thickening up to [ （23.04±5.96）% at day 3 （P =0.009）, （61.65±10.32）% for day 7 （P 〈 0.001 ）] ,the reduction of the blood flow and the increase of vascular reactivity to 5-HT when compared to con- tralateral arteries. Two weeks after collar placement, the vascular wall remodeling was observed in injured artery, such as the medial thickening for [（31.52±4.56） %,P =0.012] and a diffuse intimal hyperplasia,the reduction of the lunfinal area [（37.17±4.57）% （P 〈 0.001）] and the carotid artery blood flow. The average neointima area was （0.19±0.05） rom2 in collared arteries. The vascular reactivity to 5-HT came back to the normal level. Conclusions Collar-induced advenfitia injury caused the enhancement of vascular contractility and the neointima formation. The change of vascular contractility appeared before the formation of neointima.