Vasomotion in normal and injured spinal cord.
Blood flow in the feline thoracic spinal cord was measured, using a laser-Doppler flowmetry. Rhythmic changes in the spinal cord blood flow were repeatedly observed with a frequency of about three to eight cycles per minute, unrelated to the respiratory or cardiac cycles. These changes were unaffected by hypertension induced by angiotensin II, but disappeared when systemic blood pressure was lowered by trimethaphan or when hypercapnia was induced. CO2 responsiveness of the blood flow and postocclusive reactive hyperemia were also examined, in both the normal and injured spinal cord. CO2 responsiveness was lost 1 h after a 500 gm/cm injury without rhythmic changes, but was partially regained 2 days later, at which time rhythmic changes were frequently observed. Postocclusive hyperemia apparently diminished 1 h after a 500 gm/cm injury, but reappeared 2 days later. Vasomotion in the normal and injured spinal cord is discussed.
Mizutani
M
M
Department of Orthopedic Surgery, Faculty of Medicine, Kyoto University, Japan.
Yamamuro
T
T
Shikata
J
J
D000818:Animals; D001794:Blood Pressure; D006935:Hypercapnia / Q000503:physiopathology; D012016:Reference Values; D012039:Regional Blood Flow; D012212:Rheology; D013116:Spinal Cord / Q000098:blood supply*; D013119:Spinal Cord Injuries / Q000503:physiopathology*; D014463:Ultrasonography; D014666:Vasomotor System / Q000502:physiology* / Q000503:physiopathology