Effects Of Thyroid-stimulating Hormone On The Function Of Human Vascular Smooth Muscle Cells

Objectives: The purpose of the present research was to study the effects of TSH onhuman vascular smooth muscle cells (VSMCs) and to erplore the relationship between TSHand atherosclerosis (AS).Methods: Cell proliferation was measured by the MTT assay. Cells were analyzed usinga flow cytometer to determine the cell-cycle phase of each cell. For the purpose of detectingcyclinA and cyclinD, immunocytochemical staining and western blots were performed.Real-time PCR was used to assess the VSMCs phenotypes.Results: different concentrations of TSH could promote the transition of cell cycle phaseG2to phase M and increased the expression of cell cycle protein A and D1of VSMCs. Inaddition, the results indicated that VSMCs undergo a phenotypic transformation from acontractile state to a synthetic state after treatment with different concentrations of TSH.Conclusion: TSH can promote VSMC proliferation and accelerate AS, and it isprobably a risk factor for causing AS in people with subclinical hypothyroidism. Objective: using echo tracking technology to assess the correlation of subclinicalhypothyroidism and arterial elasticity.Methods: One hundred patients with SCH and one hundred normal controls(NC) wereenrolled to perform the thyroid function test and the level of blood lipid. Colour Dopplerultrasound was used to measure the carotid artery intima-media thickness(IMT),systoliccarotid artery diameter(Ds), peak systolic velocity(PSV), resistance index(RI),the stress andstrain elasticity coefficient(Ep),stiffness index(β),compliance(AC),single point of pulse wavevelocity(PWVβ) and augmentation index(AI)of the patients. We also detected the blood lipidsand C-reactive protein (CRP) levels of the SCH patients and the volunteers.Results: β and Ep of SCH patients was significantly higher than that of the healthycontrols （P<0.05）.AI of SCH patients was significantly lower than that of the healthycontrols （P<0.05）.In SCH patiens， according to multiple linear regression， totalcholesterol,low-density lipoprotein(LDL),CRP and TSH were independent factors of β，Epand AI.Conclusion: There is a carotid artery elasticity reduction in SCH patients group, whichhave been shown to be related to dyslipidemia，inflammation, and higher thyroid stimulatinghormone(TSH). ET technology can quickly and noninvasively evaluate the carotid arteryelasticity of the patients with SCH.