Mercury sphygmomanometer based on traditional auscultation method is widely used in primary medical institutions in China, but a large amount of blood pressure data can not be directly recorded and applied in scientific research analysis, meanwhile auscultation data is the clinical standard to verify the accuracy of non-invasive electronic sphygmomanometer. Focusing on this, we designed a miniature non-invasive blood pressure measurement and verification system, which can assist doctors to record blood pressure data automatically during the process of auscultation. Through the data playback function,the software of this system can evaluate and verify the blood pressure algorithm of oscillographic method, and then continuously modify the algorithm to improve the measurement accuracy. This study introduces the hardware selection and software design process in detail. The test results show that the system meets the requirements of relevant standards and has a good application prospect.
Auscultation ; Blood Pressure/physiology* ; Blood Pressure Determination ; Oscillometry ; Sphygmomanometers

Blood Pressure ; physiology ; Humans ; Peptidyl-Dipeptidase A

This paper presents a method of noninvasive and continuous measurement of blood pressure by pulse wave. The method is realized by extracting the characteristic parameters of human brachial artery pulse wave and developing the stepwise regression equation. The experiment results showed that blood pressure measured by this method was well correlated with which measured by mercury sphygmomanometer. The mean difference of blood pressure was smaller than 3 mmHg, and the standard deviation was smaller than 5 mmHg.
Blood Pressure ; physiology ; Blood Pressure Determination ; methods ; Blood Pressure Monitors ; Humans ; Pulse

PURPOSE: Photoplethysmography (PPG) is a noninvasive optical technology that detects changes in blood volume in the vascular system. This study aimed to investigate the possibilities of monitoring the cardiovascular system status by using PPG. MATERIALS AND METHODS: Forced hemodynamic changes were induced using cardiac stimulants; dopamine and epinephrine, and PPG components were recorded by a noninvasive method at the peripheral blood vessels. The results were compared among 6 dogs. Endotracheal intubation was performed after an intramuscular injection of 25 mg/kg ketamine sulfate, and anesthesia was maintained with 2% enflurane. After stabilizing the animals for 15 min, 16 mg/mL diluted dopamine was injected into a vein for 2 min at 20 microgram/kg.min(-1) by using an infusion pump. Thereafter, the infusion pump was stopped, and 1 mg epinephrine was injected intravenously. Fluid administration was controlled to minimize preload change in blood pressure. RESULTS: After stimulant administration, systolic blood pressure (SBP) and diastolic blood pressures (DBP) increased. The direct current (DC) component, which reflects changes in blood volume, decreased while the alternating current (AC) component, which reflects changes in vascular compliance and resistance, increased. The correlation coefficient between SBP and the foot of the DC component was 0.939 (p < 0.01), while it was 0.942 (p < 0.01) for DBP and the peak of the DC component. The AC component could predict the increase in vascular resistance from a stable pulse blood volume, even with increased pulse pressure. Conclusions: These results support the possibility that PPG components may be used for easy and noninvasive measurement of hemodynamic changes in the cardiovascular system.
Animals ; Blood Pressure/*physiology ; *Blood Pressure Monitors ; Dogs/*physiology ; Humans ; Models, Animal ; Photoplethysmography/*methods

This review systematically introduces the functional connections among cardiovascular centers from spinal cord to cortex, and the mechanisms underlying pressor or depressor response of these cardiovascular centers, including the pathways, transmitters and receptors involved. The pressor or depressor response of these cardiovascular centers is mainly mediated by RVLM-sympathetic vasoconstrictor nerve system.
Blood Pressure ; physiology ; Central Nervous System ; physiology ; Cerebral Cortex ; physiology ; Humans ; Hypothalamus ; physiology ; Medulla Oblongata ; physiology ; Spinal Cord ; physiology

The hypothalamic paraventricular nucleus (PVN) is a crucial region involved in maintaining homeostasis through the regulation of cardiovascular, neuroendocrine, and other functions. The PVN provides a dominant source of excitatory drive to the sympathetic outflow through innervation of the brainstem and spinal cord in hypertension. We discuss current findings on the role of the PVN in the regulation of sympathetic output in both normotensive and hypertensive conditions. The PVN seems to play a major role in generating the elevated sympathetic vasomotor activity that is characteristic of multiple forms of hypertension, including primary hypertension in humans. Recent studies in the spontaneously hypertensive rat model have revealed an imbalance of inhibitory and excitatory synaptic inputs to PVN pre-sympathetic neurons as indicated by impaired inhibitory and enhanced excitatory synaptic inputs in hypertension. This imbalance of inhibitory and excitatory synaptic inputs in the PVN forms the basis for elevated sympathetic outflow in hypertension. In this review, we discuss the disruption of balance between glutamatergic and GABAergic inputs and the associated cellular and molecular alterations as mechanisms underlying the hyperactivity of PVN pre-sympathetic neurons in hypertension.
Animals ; Blood Pressure ; physiology ; Excitatory Postsynaptic Potentials ; physiology ; Humans ; Hypertension ; physiopathology ; Hypothalamus ; physiology ; Neurons ; physiology ; Paraventricular Hypothalamic Nucleus ; physiology

AIMTo investigate whether if the Habenula is the main relay involved in the vasopressor effect induced by the stimulus of insular cortex, central-, lateral amygdaloid nucleus respectively.

METHODSElectrostimulation of the nuclei mention above respectively, and microinjection of lidocaine into Habenula unilaterally and bilaterally.

RESULTSWhen INS or CeA was stimulated, inducing an obvious increase of blood pressure. To stimulate INS or CeA after microinjecting lidocaine into Hb 5 minutes, the amplitudes of the vasopressor responses were decreased significantly, and the decrease of the bilaterally was larger (decreased value: 41.7% in INS, 46.1% in CeA) than that of unilaterally (decreased value: 36.9% in INS, 39.6% in CeA).

CONCLUSIONHabenula is one of the main relays involved in the vasopressor effects induced by the stimulus of insular cortex, central-, lateral amygdaloid nucleus.

Amygdala ; physiology ; Animals ; Blood Pressure ; physiology ; Cerebral Cortex ; physiology ; Electric Stimulation ; Habenula ; physiology ; Neural Pathways ; physiology ; Rats ; Rats, Wistar

OBJECTIVETo develop a system for automatically controlling carotid sinus pressure in the study on baroreceptors.

METHODSThe preparation containing carotid sinus with parts of the connected vessels and carotid sinus nerve (CS-CSN) were isolated and perfused. A critical pressure controlling component (PRE-U, Hoerbiger, Deutschland) dictated by a computer was integrated into the system to clamp the intrasinus pressure. The pressure command and the relevant intrasinus pressure were compared to evaluate the validity of the pressure controlling system.

RESULTSA variety of sinus pressure-controlling patterns, including pulsation, ramp and step pressures, could be achieved accurately by using the system, and the pressure-dependent discharge activities of sinus nerve were confirmed.

CONCLUSIONThis system for clamping carotid sinus pressure could realize multiple pressure-controlling patterns and is a useful and flexible pressure controlling method that could applied in the study on mechano-electric transduction of baroreceptors.

Animals ; Blood Pressure ; Carotid Sinus ; innervation ; physiology ; Nerve Fibers ; physiology ; Pressoreceptors ; physiology ; Rabbits

In physiology-related books, there are many relationship curves about blood flow rate in arteries and blood pressure changes with time, but there are not much explanation about such relationship. This is the very the question that the present article tries to answer. We clarified the relations between blood flow rate and blood pressure gradient using the experimental curves as the basis, using Poiseuille Law and relative knowledge of phisics and mathematics, and using analysis and reasoning. Based on the study, it can be concluded that in every course of cardiac cycle, the blood flow rate of any section in artery blood vessel is roughly synchronized with changing rate of space and time of the blood pressure, but blood flow rate is not synchronized with blood pressure.
Arterial Pressure ; physiology ; Arteries ; physiology ; Blood Flow Velocity ; physiology ; Humans ; Time

In order to study the cardiovascular hemodynamic characteristics and evaluate the blood pump, we made a series of cardiovascular simulation devices which could reflect the hemodynamics of blood circulation system by the elastic chamber model, and tested the relations between cardiovascular hemodynamic parameters (such as systole pressure, diastole pressure, average pressure, pulsative pressure, flow rate) and ventricular afterload (peripheral resistance and vascular compliance) as well as cardiac output, diastolic period, systole period and preload. The effect of the parameters on the arterial pressure and flow rate was estimated when any one of the parameters was changed. The result of simulating experiment was coincided with that deduced from mathematical model and physiologic condition. Therefore the series of cardiovascular simulation devices can reflect the hemodynamics of blood circulation.
Blood Pressure ; physiology ; Cardiac Output ; physiology ; Cardiovascular Physiological Phenomena ; In Vitro Techniques ; Models, Cardiovascular ; Vascular Resistance ; physiology