压力肌动图适用于研究微小动脉(内经>50微米)腔内的压力与直径的变化关系。实验在显微镜下进行，血管内径、外径、管腔内流量、压力和温度的改变通过计算机控制的图像分析系统实时连续的显示和记录下来。传感器连读地监测流入端和流出端的压力，水平张力可在微调控器下调节。血管腔内的压力可被压力调控器容易地调节。实验小室内的温度在温度控制装置的调控下保持恒温。实验小室的盖板上附有试液灌流装置、置换液体装置和气体供给装置。至1989年以来, 采用 Living Systems 压力肌动图进行血管生理及药理研究的全世界顶尖的研究机构和大学及药厂研究室已达五百余***。 生命科学实验研究发表的科学论文2007年已达***千多篇。

压力肌動圖系統包括以下几個部分:

肌动图系统：实验小室，中央控制及其信息转换装置，实验小室盖板，校准装置及其负压活舌。
压力调控系统：压力调控器：0 - 250 mmHg
数椐获取及其分析系统：倒置显徽镜、 C-接口、CCD摄像机，图像摄取I/O装置，计算机及其数椐获取/分析软件系统。

應用范圍:
基本特性: 小血管, 大血管, 血管壁厚度的測量,兩個血管的對比研究,不同种類的動物血管對比研究及其同類動物不同血管的對比研究,對局部血管反應性的評估, 人體不同血管的研究 .
血管反應机理的研究: 血管內皮：血管內皮分泌的舒張因子（***氧化氮）, 前列腺素以及血管內皮分泌的超极化因子 ;
平滑肌: 鈣通道、鉀通道的作用机理
受體研究: 受體定位和作用特征研究, 激素,神經遞質及其它激動劑的影響
药物机理的研究 : ＡＣＥ***抑制劑, 洋地黃及其胰島素作用机理的研究
生理學研究 : 年齡, 怀孕, 麻醉 ;
病理學研究: 高血壓, 脂肪沈滯性動脈硬化症, 糖尿病, 缺血症, 腫瘤, 心臟病, 肺疾病;
深入研究的可能性: 電生理實驗(膜電位的測定), 細胞內离子和其它物質的螢光測定
密封的、单血管室：CH/1/AU CH/1/AU/SH

应用：1. 长期血管灌注 2. 血管培养 3. 基因转移 4. 重塑研究 5. 血管外压迫
压力控制和流量控制PS/200型：
•压力模式：建立并自动维持0-200mmHg之间的所选压力
•流动模式：产生可调节的、稳定的灌注速度，范围为3 µl/min至2.5 ml/min。其压力传感器，可检测并控制微型蠕动泵的压力。 Extravascular Pressure Control System

***新产品: 血管外压力肌动图
即将血管压力(EvP)应用于安装在密封室中的离体插管的和有压力的血管外。 特别对心肌、骨骼肌和受到肌肉组织持续不变、脉动压力的血管(血管是嵌入肌肉组织中的), 对这些血管可进行研究，以测量经常发生的功能变化在心血管疾病中的意义，并分析潜在的机理。
1. EV-1型血管外压力控制器和SG-1型信号发生器。简单地说，当单独应用时，EV-1型产生可选择的、持续不变的EvP，起中间环节的作用，允许SG-1产生正弦的、脉动的血管外压力波形。
2. CH/1/AU型密封血管室及其自加热姊妹型即CH/1/AU/SH型，是本系统的关键部件。

系统压力的基本来源，是***个实验室压缩气缸和***个调节(用户提供)，使压力降低至6-8psi。
然后，此压力由经过电子饲服阀从EV-1接收到的信号调节，产生所需要的稳定的或不稳定的血管外室压力。 饲服阀是EV-1的***个部件。

Function – The instruments provide a means for applying extravascular pressures (EvP) to excised, cannulated and pressurized vessels mounted in a sealed chamber. In particular, for cardiac, skeletal muscle and other vessels subjected to sustained or pulsatile pressures from the muscular tissue in which they are embedded. Studies can be carried out on these vessels to determine whether the functional changes that often occur may have local or distal significance in cardiovascular disease, and for analyzing underlying mechanisms.
System Components – The two instruments explained in more detail below are the Extravascular Pressure Control, Model EV-1 and the Signal Generator, Model SG-1. Briefly, the EV-1 produces selectable, sustained EvP when used alone, and acts as an intermediate link allowing the SG-1 to create sinusoidal and pulsatile extravascular pressure waveshapes.
The sealed vessel chambers, Model CH/1/AU or its self-heated cousin Model CH/1/AU/SH are key components of this system. These chambers are described elsewhere on our website.
A laboratory compressed gas tank and a regulating valve (user supplied) for reducing the pressure to 6 to 8 psi is the fundamental source of system pressure. It is then modified by signals received from the EV-1 via the Electronic Servo Valve to create the desired steady or non-steady extravascular chamber pressures. The servo valve is included as part of the EV-1.

EV – 1 Pressure Control Unit –
The extravascular pressure (EvP) in the sealed chamber is sensed by a solid-state pressure transducer. The signal from this transducer is connected to the EV-1 Control Unit where it is compared with either the internal pressure signal set by the EV-1 pressure dial, or one of the external pressure signals fed into either the Function Generator or Signal Generator input jacks. Any difference between these two signals regulates the Electronic Servo Valve output pressure so that the two presures are the same.
Internal Pressure Signal Mode: Here, the signal corresponding to the Pressure Dial setting calibrated in mmHg establishes the extravascular chamber pressure. This pressure is sustained until a new presure is selected. The panel meter reading also shows the chosen extravascular pressure in mmHg which can be accessed for data acquisition at the rear panel Pressure Signal jack.
External Pressure Signal Mode: When switched to this mode, various extravascular pressure waveshapes can be created to match external input signals. Again, the actual extravascular pressure can be accessed for data acquisition at the rear panel Pressure Signal jack.
Function Generator signals can be obtained from a computer program written by the user and a computer having a D/A computer board that supplies analog voltages of 10 mV/mmHg. In this way, various simple or complex, time-dependent pressures can be applied to the chamber.
Signal Generator – The Model SG-1 is used to establish sinusoidal and pulsatile extravascular waveshapes as described ahead.
EV-1 Specifications
Pressure Range: 0 – 250 mmHg
Pressure Output Signal: 10 mV/mmHg
External Input Signal: 10 mV/mmHg
Power: 100-120 VAC/60 Hz or 200-240VAC/50Hz
Size/Weight: 13 x 11 x 36 cm (H x W x L)/3.1 kg
Applications

Over 420 papers have been published using Living System Instrumentation's cannulated blood vessel system. We have compiled a bibliography, which may be accessed by clicking Bibliography. Available in Adobe Acrobat for search use.

A Host of Applications using these tools are at the disposal of the research investigator interested in obtaining new insights into the mechanisms of vascular function in human health and disease.

Typical Examples -

Studies: hypertension, diabetes, aging, and pregnancy

Tissue Sources: humans, primates, swine, rats, dogs, and rabbits

Vascular Beds: cerebral, coronary, lung, skin, and kidney

Vasoactive Agents: NO, endothelin, estrogen, peptides, and oxygen

Simultaneous Measurements: Fluorescence & Vessel Diameter

Changes in diameter of rat gracilis arterioles as a function of perfusate flow

From: Koller A, Sun D, Huang A, Kaley G

Co-release of nitric oxide and prostaglandins mediates flow-dependent dilation of gracilis muscle arterioles. Am J Physiol 1994; 267:H326-H33
 

Depolarization and constriction of rat myogenic cerebral arteries with tone by the KCA channel inhibitor iberiotoxin

From: Nelson MT , Cheng H, Rubart M, Santana LF, Bonev AD, Knot HJ, Lederer WJ

Relaxation of arterial smooth muscle by calcium sparks. Science 1995;270:633-637

Pressure = 60 mmHg
 

Coronary microvessel responses of normal and atherosclerotic monkeys to acetylcholine

Vessel diameters = 122 - 220 µm

From: Sellke FW, Armstrong ML, Harrison DG

Endothelium-dependent vascular relaxation is abnormal in the coronary microcirculation of atherosclerotic primates. Circ 1990;81:1586-1593
 

Spontaneous vasomotion of cerebral artery diameter as a function of temperature

Pressure = 80 mmHg

From: Osol G, Halpern W

Spontaneous vasomotion in pressurized cerebral arteries from genetically hypertensive rats. Am J Physiol 1988;254 (Heart Circ Physiol 23):H28-H33
 

Oxygen reactivity of an isolated rat cremaster muscle arteriole

Pressure = 65 mmHg; ID = 77 µm

From: Messina EJ, Sun D, Koller A, Wolin MS, Kaley G

Increases in oxygen tension evoke arteriolar constriction by inhibiting endothelial prostaglandin synthesis. Microvasc Res 1994;48(2):151-160
 

Quick Summary
Single & Dual Vessel Chamber Models
For Perfusion of Isolated, Cannulated Vessels
These chambers are machined from an inert plastic (PET) that has chemical and physical properties superior to acrylics. The chambers can be readily mounted on the microscope mechanical stage for adjustment of the image field.
Single Vessel Chambers- Most can be supplied with Pt stimulation electrodes for electrical neurotransmitter release from the nerve varicosities. Add /S to model number for this option. All of these chambers are ideal for applications requiring confocal microscopy and simultaneous fluorescence and diameter measurements. For ratiometric fluorescence and vessel dimensioning data acquisition systems, consider IonOptix www.ionoptix.com.
Picture Model Description
CH/1/AU Sealed chamber for applying extravascular pressures to a perfused, pressurized vessel and for long-term perfusion experiments. Bath volume: 3-5 ml. Requires superfusion for warming bath.
CH/1/AU/SH Similar to CH/1/AU, but includes Self-Heated bath and temperature controller. May be used with or without superfusion.
CH/1 For fluorescent, confocal, and many other applications. Requires superfusion for warming bath.
CH/1/SH Same as CH/1 but includes Self-Heated bath and temperature controller. May be used with or without superfusion.
CH/1/QT For rapid freezing or fixation of cannulated, pressurized vessel
CH/1/R For axially rotating or inverting a cannulated, pressurized vessel.

Dual Vessel Chambers - Most can be supplied with Pt stimulation electrodes for electrical neurotransmitter release from the nerve varicosities. Add /S to model number for this option.
Picture Model Description
CH/2/A Separate baths; 8 ml bath volume; requires superfusion for warming bath.
CH/2/E Separate baths; 8 ml bath volume; removable cover for control of gas environment above baths; requires superfusion for warming bath.
CH/2/SH Separate baths; 2 ml bath volume; Self-Heated baths and temperature controller; non-superfused baths.

Pressure
Control and Measurement
Model PS/200
This Pressure Servo and Peristaltic Pump instrument has two modes of operation.
Pressure mode - Establishes and automatically maintains any selected pressure between 0 and 200 mmHg.
Flow mode - Produces an adjustable, stable perfusion rate in the range of 3 µl/min to 2.5 ml/min.
A solid-state pressure transducer placed in a biological preparation setup, such as a cannulated vessel, senses the pressure for control of the miniature peristaltic pump. This pump supplies physiological perfusates from a reservoir to generate and hold a particular pressure, or flow; each can be independently determined by the setting of pre-calibrated dials. Pressure is indicated directly in mmHg on a digital panel meter in both modes, and is available as an analog output voltage for data acquisition. Pressure may also be programmed through an external voltage signal applied to the instrument. Additional information can be found in Q&A.
Model PS/20
This instrument is similar to the PS/200 except that the maximum pressure range is 20 mmHg. It is especially useful for low pressure vessel experiments on veins, airways and lymphatics.

Features
Linear calibration of pressure and flow signals
Flow-thru pressure transducers · Pressure or flow values easily changed
Pump can be positioned relatively near to the vessel chamber to minimize perfusion time

Applications
Maintain transmural pressure during flow changes
Examine myogenic responses
Deliver vasoactive agents intralumenally
Determine concentration/response