USE OF CRYOMICROTOMY TO STUDY GASTRIC DIFFUSION OF AMOXICILLIN IN GUINEA-PIGS

Cryomicrotomy has been used as a new technique for removing gastric mu cosae from adult guinea pigs for the study of amoxicillin secretion ac ross gastric mucosae. This method allowed a very regular thickness of the removed surface layer of mucosa to be obtained with good reproduci bility. Gastric superficial mucosa con centrations and gastric juice c oncentrations of amoxicillin were determined 1, 2, and 3 h after intra muscular administration (50 mg/kg) in 21 guinea pigs by a microbiologi cal method. No antibiotic was detected in gastric samples at 4 h, exce pt for a low-level mucosal concentration in one animal, thus indicatin g the short time that amoxicillin is present in gastric samples.