title: Effects of anaesthesia induction drugs on circulation in denervated intestinal loop preparation.
abstract: The effect of anaesthesia induction drugs on the intestinal circulation was evaluated in an isolated loop preparation in 28 dogs. Selected intestinal loops were perfused with aortic blood by a pump at a constant pressure of 100 mmHg. A mixture of 86Rb and 9 microns spheres labeled with 141Ce was injected into the arterial cannula supplying the intestinal segment while mesenteric venous blood was collected for activity counting. Diazepam in a dose of 3 mg X kg-1 was accompanied by a significantly lower clearance (Cl-Rb), and permeability-surface area product (PS) than pentobarbitone; there were no differences between diazepam and pentobarbitone in total blood flow (BF), vascular resistance (VR) and oxygen consumption in the intestinal segments. Circulatory variable observed after midazolam, 8 mg X kg-1 and an additional 16 mg X kg-1, did not significantly differ from those seen during pentobarbitone. Ketamine in a dose of 8 mg X kg-1 was accompanied by a significantly lower BF, Cl-Rb, microsphere entrapment (Cl-Sph), PS, and higher VR and arterio-venous oxygen content difference. Sixteen mg X kg-1 of ketamine did not lead to any additional changes in determined variables of the intestinal circulation. Alpha-adrenoceptor blockade completely abolished vasoconstriction caused by ketamine, suggesting that the long-lasting vasoconstricting effect of ketamine on the intestinal circulation is mediated through catecholamines.
authors.forename: M
authors.initials: M
authors.lastname: Tverskoy
authors.forename: S
authors.initials: S
authors.lastname: Gelman
authors.forename: K C
authors.initials: KC
authors.lastname: Fowler
authors.forename: E L
authors.initials: EL
authors.lastname: Bradley
mesh_terms: D000758:Anesthesia; D000818:Animals; D001569:Benzodiazepines / Q000494:pharmacology*; D001794:Blood Pressure; D003714:Denervation; D003975:Diazepam / Q000494:pharmacology*; D004285:Dogs; D066298:In Vitro Techniques; D007421:Intestine, Small / Q000098:blood supply* / Q000294:innervation; D007649:Ketamine / Q000494:pharmacology*; D008657:Metabolic Clearance Rate; D008874:Midazolam; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption / Q000187:drug effects; D010313:Partial Pressure; D010424:Pentobarbital / Q000494:pharmacology*; D012039:Regional Blood Flow / Q000187:drug effects; D012413:Rubidium / Q000097:blood; D014655:Vascular Resistance / Q000187:drug effects
chemical_list: D001569:Benzodiazepines; D007649:Ketamine; D010424:Pentobarbital; D012413:Rubidium; D003975:Diazepam; D008874:Midazolam; D010100:Oxygen