एक<em> पूर्व vivo</em> तैयारी दोनों vasoactive उत्तेजनाओं संवहनी प्रतिक्रियाएं और निष्क्रिय दीवार यांत्रिकी के माध्यम से बुनियादी संरचनात्मक गुणों के आकलन के पूछताछ के लिए सबसे बड़ा gracilis मांसपेशी प्रतिरोध arterioles अलगाव के लिए वर्णित है.
The isolated microvessel preparation is an ex vivo preparation that allows for examination of the different contributions of factors that control vessel diameter, and thus, perfusion resistance1-5. This is a classic experimental preparation that was, in large measure, initially described by Uchida et al.15 several decades ago. This initial description provided the basis for the techniques that was extensively modified and enhanced, primarily in the laboratory of Dr. Brian Duling at the University of Virginia6-8, and we present a current approach in the following pages. This preparation will specifically refer to the gracilis arteriole in a rat as the microvessel of choice, but the basic preparation can readily be applied to vessels isolated from nearly any other tissue or organ across species9-13. Mechanical (i.e., dimensional) changes in the isolated microvessels can easily be evaluated in response to a broad array of physiological (e.g., hypoxia, intravascular pressure, or shear) or pharmacological challenges, and can provide insight into mechanistic elements comprising integrated responses in an intact, although ex vivo, tissue. The significance of this method is that it allows for facile manipulation of the influences on the integrated regulation of microvessel diameter, while also allowing for the control of many of the contributions from other sources, including intravascular pressure (myogenic), autonomic innervation, hemodynamic (e.g., shear stress), endothelial dependent or independent stimuli, hormonal, and parenchymal influences, to provide a partial list. Under appropriate experimental conditions and with appropriate goals, this can serve as an advantage over in vivo or in situ tissue/organ preparations, which do not readily allow for the facile control of broader systemic variables.
The major limitation of this preparation is essentially the consequence of its strengths. By definition, the behavior of these vessels is being studied under conditions where many of the most significant contributors to the regulation of vascular resistance have been removed, including neural, humoral, metabolic, etc. As such, the investigator is cautioned to avoid over-interpretation and extrapolation of the data that are collected utilizing this preparation. The other significant area of concern with regard to this preparation is that it can be very easy to damage cellular components such as the endothelial lining or the vascular smooth muscle, such that variable source of error can be introduced. It is strongly recommended that the individual investigator utilize appropriate measurements to ensure the quality of the preparation, both at the initiation of the experiment and periodically throughout the course of a protocol.
प्रस्तुत एक कंकाल की मांसपेशी microvessel के अलगाव को हटाने, और डबल केन्युलेशन के प्रोटोकॉल का वर्णन है, हालांकि यह सामान्य तकनीक आसानी से सबसे ऊतकों को लागू किया जा सकता है. वर्तमान पांडुलिपि शब्द "धमनिका"…
The authors have nothing to disclose.
इस काम अमेरिकन हार्ट एसोसिएशन (0740129N ईआईए) और NIH HL90610 T32 के द्वारा समर्थित किया गया था.
Reagents and Equipment | Company | Comments/Catalogue # |
Vessel Chamber | Custom | Dave Eick (MCW) |
Heated Circulating Water Bath | PolyScience and Haake | Haake DC 10 |
Pipets | Frederick Haer & Co. | Capillary Tubing 2.0 mm OD x 1.0 mm ID (27-33-1) |
Pressure Monitor | World Precision Instruments | |
Water Jacketed Reservoir | Custom | |
External Light Source | World Precision Instruments | Novaflex |
Pipet Puller | MicroData Instruments | PMP102 Micropipet Puller |
Full complement of surgical tools | Fine Science Tools | Dumont |
Ultra Fine Forceps | Fine Science Tools | Inox #5 |
Silk Suture Thread | Ethilon | #10-0 or 9-0 |
Stereo Microscope | Olympus | Olympus SZ-11 |
Analog Video Calipers | Boeckeler | Via Controller (Via-100) |
High Resolution Analog Camera | Panasonic | GP-MF 602 |
Oxygen Tank | Regional | 21% balance nitrogen and 5% CO2 balance nitrogen |
Tubing | Tygon | |
Drain Pump | Cole Parmer Instrument Co. | |
Modified Rat PSS | See recipe below | |
Van Breemen’s Relaxant PSS | See recipe below |
Table 1. A list of the major components of isolated microvessel station setup presented in the Figures.
Modified Rat PSS Recipe | To make two liters of PSS | 20X Salt Stock (2L) | 20X Buffer Stock (2L) |
NaCl | 278.0 g | ||
KCl | 14.0 g | ||
MgSO4-7H2O | 11.5 g | ||
CaCl2-H2O | 9.4 g | ||
NaHCO3 | 80.8 g | ||
EDTA | 0.4 g | ||
NaH2PO4 | 0.28 g | ||
Glucose | 1.98 g | ||
20x Salt Stock | 100 mL | ||
20x Buffer Stock | 100 mL | ||
Distilled Water | 1800 mL |
Table 2. Recipe for standard physiological salt solution (PSS) used in the isolated microvessel protocols.
Comments on Recipe: Make 2 L of Salt Stock and 2 L of Buffer Stock. These can be refrigerated when not being used, but shake them well and often before preparing PSS. The additional ingredients are added at the time of preparation of final PSS.
Van Breemen’s Relaxant PSS | To make 2 liters of PSS | 20X Salt Stock (1L) | 20X Buffer Stock (1L) |
NaCl | 107.4 g | ||
KCl | 7.0 g | ||
MgSO4-7H2O | 5.76 g | ||
MgCl2-6H2O | 81.32 g | ||
NaHCO3 | 40.4 g | ||
EDTA | 0.2 g | ||
EGTA | 15.22 | ||
NaH2PO4 | 0.28 g | ||
Glucose | 1.98 g | ||
20x Salt Stock | 100 mL | ||
20x Buffer Stock | 100 mL | ||
Distilled Water | 1800 mL |
Table 3. Recipe for Van Breemen’s relaxant physiological salt solution (PSS) used in the isolated microvessel protocols under conditions of zero active tone.
Comments on Recipe: Make 1 L of Salt Stock and 1 L of Buffer Stock. These can be refrigerated when not being used, but shake them well and often before preparing PSS. The additional ingredients are added at the time of preparation of final relaxant PSS.