Effects of fedotozine on gastrointestinal motility in dogs: mechanism of action and related pharmacokinetics.
The effects of fedotozine, (+)-(1R)-1-phenyl-1-[(3,4,5-trimethoxy)benzyloxymethyl]-N,N-dim eth yl- n-propylamine, on motility of the antrum and small intestine were investigated in dog. In fasted dogs, following i.v. administration, fedotozine at 1 and 2 mg kg-1 stimulated and at 5 mg kg-1 inhibited antral motility. Between 1 to 5 mg kg-1, fedotozine exhibited a sustained and potent stimulatory effect on the small intestine inducing 1 to 4 phases III of the migrating motor complex (MMC) lasting up to 32 min in the duodenum and migrating to the jejunum. Following oral administration, fedotozine at 2.5 and 5 mg kg-1 constantly stimulated both antrum and small intestinal motility. In fed dogs, fedotozine i.v. (2 mg kg-1) increased antral motility and induced phase III of MMC in the place of postprandial pattern. Naloxone (0.3 mg kg-1 i.v.) and naloxone methylbromide (2 mg kg-1 i.v.) inhibited the stimulatory effects of fedotozine on gastrointestinal motility indicating a peripheral opiate site of action of the drug whereas phentolamine, hexamethonium, propranolol and methysergide were inactive. In-vitro fedotozine showed submicromolar affinity for opiate receptors with a weak specificity for the mu-receptors in guinea-pig brain and myenteric plexus preparations. Plasma concentrations in dogs receiving fedotozine administered orally at 2.5 mg kg-1 (and in all dogs except one at 5 mg kg-1) were below the detection limit (less than 20 ng g-1). In contrast, tissue concentrations in the muscle and mucosal layers of the gut were above 1 microgram g-1.(ABSTRACT TRUNCATED AT 250 WORDS)
Pascaud
X
X
Jouveinal Laboratories, Fresnes, France.
Honde
C
C
Le Gallou
B
B
Chanoine
F
F
Roman
F
F
Bueno
L
L
Junien
J L
JL
D000284:Administration, Oral; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001593:Benzyl Compounds / Q000493:pharmacokinetics / Q000494:pharmacology*; D004285:Dogs; D005215:Fasting / Q000378:metabolism; D005260:Female; D005750:Gastric Juice / Q000737:chemistry / Q000378:metabolism; D005769:Gastrointestinal Motility / Q000187:drug effects*; D007275:Injections, Intravenous; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D011437:Propylamines / Q000493:pharmacokinetics / Q000494:pharmacology*; D011957:Receptors, Opioid / Q000378:metabolism
D001593:Benzyl Compounds; D011437:Propylamines; D011957:Receptors, Opioid; D009270:Naloxone; D001285:Atropine; C067749:fedotozine