title: Assessing Myogenic Response and Vasoactivity In Resistance Mesenteric Arteries Using Pressure Myography.
abstract: Small resistance arteries constrict and dilate respectively in response to increased or decreased intraluminal pressure; this phenomenon known as myogenic response is a key regulator of local blood flow. In isobaric conditions small resistance arteries develop sustained constriction known as myogenic tone (MT), which is a major determinant of systemic vascular resistance (SVR). Hence, ex vivo pressurized preparations of small resistance arteries are major tools to study microvascular function in near-physiological states. To achieve this, a freshly isolated intact segment of a small resistance artery (diameter ~260 μm) is mounted onto two small glass cannulas and pressurized. These arterial preparations retain most in vivo characteristics and permit assessment of vascular tone in real-time. Here we provide a detailed protocol for assessing vasoactivity in pressurized small resistance mesenteric arteries from rats; these arteries develop sustained vasoconstriction - approximately 25% of maximal diameter - when pressurized at 70 mmHg. These arterial preparations may be used to study the effect of investigational compounds on relationship between intra-arterial pressure and vasoactivity and determine changes in microvascular function in animal models of various diseases.
authors.affiliation: Section of Gastroenterology and Hepatology, Georgia Regents University.
authors.forename: Ravirajsinh N
authors.initials: RN
authors.lastname: Jadeja
authors.affiliation: Division of Gastroenterology and Hepatology, University of Pittsburgh School of Medicine.
authors.forename: Vikrant
authors.initials: V
authors.lastname: Rachakonda
authors.affiliation: Vascular Biology Center, Georgia Regents University.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Bagi
authors.affiliation: Section of Gastroenterology and Hepatology, Georgia Regents University; SKHURANA@gru.edu.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Khurana
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D008297:Male; D008638:Mesenteric Arteries / Q000033:anatomy & histology / Q000502:physiology*; D009213:Myography / Q000379:methods*; D011312:Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D014655:Vascular Resistance / Q000502:physiology; D014661:Vasoconstriction / Q000502:physiology