title: Microendoscopy of the synovial vasculature in the rabbit knee joint.
abstract: The functional morphology of the synovial vasculature in the rabbit knee joint was investigated using our technique of microendoscopy, which involves an in vivo microscopy via a 1.9-mm endoscope. In the vessels of the fibrous tissue of the joint capsule it was found that after intraarticular administration of epinephrine the blood flow and the vascular diameters decrease for 3-5 min. In the areolar part of the synovial tissue, an external elevation of the intraarticular pressure causes collapse of the capillaries at 10-15 mm Hg, whereas the collapse pressure of the arterioles is 30-40 mm Hg. Intraarticular application of Neuropeptide Y (NPY) leads to a marked vasoconstriction including the arteriovenous anastomoses, whereas after epinephrine the arteriovenous anastomoses remain patent or dilate during the arteriolar constriction phase. It is concluded that the technique of microendoscopy allows a valuable in vivo investigation of the synovial microvasculature.
mesh_terms: D000818:Animals; D001182:Arthroscopy / Q000379:methods*; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure; D004837:Epinephrine / Q000008:administration & dosage; D007270:Injections, Intra-Articular; D007719:Knee Joint / Q000098:blood supply*; D008297:Male; D008833:Microcirculation / Q000033:anatomy & histology / Q000187:drug effects; D018715:Microscopy, Video; D009478:Neuropeptide Y / Q000008:administration & dosage; D011817:Rabbits; D013583:Synovial Membrane / Q000098:blood supply*; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D009478:Neuropeptide Y; D004837:Epinephrine