Abstract: Intake of drinking water eroded by sea water will lead to changes in hemodynamics and vascular biomechanical features,affect the blood supply of the arterial and vascular system.In this study,we investigated the hemodynamic changes in mice fed with seawater,observed the spontaneous contraction characteristics of isolated smooth muscle specimens of carotid artery.Kunming mice were randomly divided into seawater feeding group,seawater feeding + additive group,normal feeding group,normal feeding + additive group.After 4 weeks of feeding,the pressure waveform of common carotid artery was observed,and the enhanced pressure of central artery was calculated according to the breakpoint of systolic blood pressure rising phase,and the ejection time was calculated according to the notch of arterial pulse.The vascular rings of common carotid artery wall were removed to record the characteristics of myogenic autonomous contraction under stretching in vitro.The results indicated that heart rate and ejection period of the mice drank seawater for 4 weeks were significantly accelerated,the breakpoint of the ascending phase of the common carotid artery systolic pressure wave was significantly increased.The central artery enhanced pressure was decreased,carotid artery enhanced blood flow index was decreased.The maximal amplitude of myogenic autonomic contraction of common carotid artery wall increased significantly.Supplementary feeding with additives was effective in alleviating heart rate,prolonging ejection period,improving systolic blood pressure and pulse pressure amplitude of central artery in seawater mice,but had limited effect on diastolic blood pressure.Long-term intake of seawater can form a new hypertension model in mice,which can affect the changes of carotid artery hemodynamics and local blood supply.

Key words: salinity water uptake, carotid arterial pressure, hemodynamic, myogenic spontaneous contraction