Gastric model

SAiRAM K, RAO 0 v, BABU M D, GOEL R K (2001) Prophylactic and curative effects ofBacopa monniera in gastric ulcer models. Phytomedicine. 8 423-30. 

We have linked the gastric cancer model of Sugimura to the examination of the occurrence of human gastric cancer and to consideration of the underlying mechanisms ... 

One-to-one random copolymers of acrylic acid with either hydroxyethyl acrylate (a hydrogel model) or methyl acrylate failed to protect insulin from release under gastric conditions (Figure 6). In the case of the hydrogel, the expected swelling due to exposure to water occurred, releasing insulin. The behavior of the ester copolymer led to the prediction that there should be no more than about four carbon atoms per carboxylic acid group in a repeat unit of the polymers. We have not been able to disprove this hypothesis thus far. 

The absorption of class III drugs is limited by their permeability over the intestinal wall. Thus, as this process is not at all modeled by the classical in vitro dissolution test, no IVIVC should be expected. When drug dissolution becomes slower than gastric emptying, a reduction in the extent of bioavailability will be found in slower dissolution rates as the time when the drug is available for permeation over the gut wall in the small intestine will then be reduced. Thus, the same type of relationship can be expected between bioavailability and in vitro dissolution, as shown in Fig. 21.12 for a class I drug. 

The activities of the indole carbazimidamide derivatives 5 at the 5-HT4 receptor were measured in vitro using the field-stimulated LMMP-GPI preparation (Table 1) followed by in vivo investigations applying the gastric emptying and intestinal transit models in the guinea-pig and rat. 

Gupta, B. L. (1989). The relationship of mucoid substances and ion and water transport, with new data on intestinal goblet cells and a model for gastric secretion. In Mucus and Related Topics, eds. Chantler, E. and Ratcliffe, N. A., The Company of Biologists, Cambridge, pp. 81-110. 

Gastric Emptying Rate and Gastric pH Changes A New Model... 

The two media typically used include Simulated Gastric Fluid (pH 1-pH 3) and Simulated Intestinal Fluid (pH 6-pH 7). The drug substance under investigation is introduced, and its uptake in the diffusion cell ( absorption ) is governed by its hydrophilic-lipophilic balance (HLB). The absorption model proposed by Strieker (26) in the early 1970s therefore effectively took into consideration (in an experimental sense) all aspects considered by the theory of the BCS, which was introduced more than 20 years later. 

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