Texas Wesleyan University 1 article published in JoVE Medicine Evaluation of Vascular Control Mechanisms Utilizing Video Microscopy of Isolated Resistance Arteries of Rats Kathleen M. Lukaszewicz1, Matthew J. Durand2, Jessica R.C. Priestley3, James R. Schmidt4, L. Adrienne Allen5, Aron M. Geurts3, Julian H. Lombard3 1Department of Physical Therapy, Marquette University, 2Medical College of Wisconsin, 3Department of Physiology, Medical College of Wisconsin, 4Graduate Programs of Nurse Anesthesia, Texas Wesleyan University, 5Office of Research, Medical College of Wisconsin This manuscript describes in vitro video microscopy protocols for evaluating vascular function in rat cerebral resistance arteries. The manuscript also describes techniques for evaluating microvessel density with fluorescently labeled lectin and tissue perfusion using Laser Doppler Flowmetry.