Gastric-acidity-controlled rabbits: control of gastric pH of rabbits by the use of antacids.

A method for controlling the gastric pH of rabbits to low acidity (pH > 4) by using different antacids was investigated, and the physiological state of rabbits during gastric-acidity control and repeated bioavailability tests was also examined in terms of hemocytological and clinicobiochemical parameters. Neither dried aluminum hydroxide gel (DAH) nor synthetic aluminum silicate (SAS) could elevate the gastric pH to more than 4. In the case of sodium bicarbonate (SBB), the gastric pH increased transiently to around 6 immediately after ingestion of the diet containing SBB and then decreased rapidly to the region of high acidity (pH < 3). On the other hand, magnesium aluminosilicate (MAS) could maintain the gastric pH in the range from 4 to 6 over a