Gastric pH profile and its control in fasting beagle dogs.

The gastric pH of fasting beagle dogs was measured by using an ion-selective field effect transistor pH sensor. In addition, a novel procedure to control the gastric pH in fasting beagle dogs was investigated. Inter- and intra-day variations in the gastric pH of the dogs were observed. The gastric pH of the dogs could be controlled by a single intravenous administration of omeprazole, an H+, K+-adenosine triphosphatase (ATPase) inhibitor (1 mg/0.25 ml/kg). The pH in the stomach was 6.6 +/- 0.2 (mean +/- S.D., n = 6) at 1 h after the omeprazole treatment, and this level of pH was maintained for a period of at least 3 h. Beagle dogs in which the gastric pH has been controlled by omeprazole are considered to be useful as an animal model to be used for the pharmaceutical evaluation of drugs in subjects with a low acidity level.