title: Autonomic control of the regional hemodynamic response to scald.
abstract: Ultrasonic flow probes were placed around the ascending aorta and each femoral artery of dogs to record cardiac index and femoral blood flow, respectively. Intravenous hexamethonium (n = 5) produced 30% decreases in systemic mean arterial pressure and in cardiac index, and a 14% increase in femoral blood flow, effects that waned over time, consistent with the half-life of the agent. Without hexamethonium, hind paw scalding with boiling water for 5 sec (n = 5) caused a marked increase in ipsilateral femoral artery blood flow (70.7 +/- 8.9 ml/min pre-burn vs 243.7 +/- 23.7 ml/min 5 min post-burn) that persisted for the 3 hr observation period. Contralateral femoral blood flow, systemic mean arterial pressure, and cardiac index were unchanged. Compared to burn only dogs, pre-burn treatment with hexamethonium (n = 6) blunted the femoral vasodilator response to burn (78.8 +/- 9.7 ml/min pre-burn vs 116.5 +/- 7.5 ml/min 5 min post-burn). These data suggest that postganglionic autonomic nerves are at least partially responsible for mediation of the regional vasodilator response to thermal injury.
authors.affiliation: Department of Surgery, Tulane University School of Medicine, New Orleans, LA 70112.
authors.forename: P
authors.initials: P
authors.lastname: Taheri
authors.forename: E
authors.initials: E
authors.lastname: Choe
authors.forename: H
authors.initials: H
authors.lastname: Lippton
authors.forename: A
authors.initials: A
authors.lastname: Hyman
authors.forename: L
authors.initials: L
authors.lastname: Flint
authors.forename: J
authors.initials: J
authors.lastname: Ferrara
mesh_terms: D000818:Animals; D001341:Autonomic Nervous System / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects; D002056:Burns / Q000503:physiopathology*; D002302:Cardiac Output / Q000187:drug effects; D004285:Dogs; D005263:Femoral Artery / Q000502:physiology; D006439:Hemodynamics / Q000187:drug effects; D018738:Hexamethonium / Q000494:pharmacology; D006614:Hindlimb / Q000098:blood supply; D012039:Regional Blood Flow; D014655:Vascular Resistance / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
chemical_list: D018738:Hexamethonium