Semi-invasive laser-Doppler flowmetry technique. New application for recordings of hemodynamics in combination with manometry of human small intestine.
A small-bowel manometry tube was supplied with two single-fiber microprobes, which recorded blood flow in the proximal small intestine by the laser-Doppler flowmetry (LDF) technique. In all experiments, saline was infused intravenously as control during the first migrating motor complex (MMC) cycle, and a drug or another saline control given intravenously during the second MMC cycle. Recordings were performed during phase 1 of MMC, i.e. when motor pattern showed quiescence. Adrenaline increased blood perfusion values by 140% in proximal duodenum and 95% in distal duodenum. The alpha 2-adrenoceptor agonist clonidine decreased the corresponding values by 34 and 25%, respectively, while oxymetazoline decreased perfusion by 33 and 44% at the same levels. The beta-adrenoceptor agonist isoprenaline increased blood perfusion values by 172% in the proximal duodenum and 194% in the distal duodenum, whereas the antagonist propranolol decreased the corresponding values by 45 and 52%, respectively. In a separate group of subjects, propranolol was given after adrenaline. The increase in blood perfusion regularly seen after adrenaline was blocked after propranolol administration. In conclusion, our findings validate semi-invasive LDF technique for studies of hemodynamics in human small intestine under basal motor conditions and in drug-induced blood flow changes.
Thollander
M
M
Department of Medicine, Karolinska Hospital, Stockholm, Sweden.
Hellström
P M
PM
Gazelius
B
B
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000328:Adult; D003000:Clonidine / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D005769:Gastrointestinal Motility / Q000187:drug effects; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D066298:In Vitro Techniques; D007421:Intestine, Small / Q000098:blood supply*; D007545:Isoproterenol / Q000494:pharmacology; D017078:Laser-Doppler Flowmetry / Q000379:methods*; D008297:Male; D008365:Manometry; D016065:Myoelectric Complex, Migrating / Q000187:drug effects; D010109:Oxymetazoline / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D012039:Regional Blood Flow / Q000502:physiology; D013696:Temperature
D000316:Adrenergic alpha-Agonists; D000319:Adrenergic beta-Antagonists; D010109:Oxymetazoline; D011433:Propranolol; D007545:Isoproterenol; D003000:Clonidine; D004837:Epinephrine