Feasibility of the Ussing chamber technique for the determination of in vitro jejunal permeability of passively absorbed compounds in different animal species.

The research focused on testing the effectiveness of the Ussing chamber technique to measure the permeability of certain drugs (acetaminophen and ketoprofen) through the small intestine (jejunum) in different animal species. Results showed that this technique is more suited for studies within a single species, not between different species, due to variances in tissue fragility and thickness.

Study Overview

• The research aimed to determine the viability of using the Ussing chamber method to investigate the permeability of the small intestine (specifically the jejunum) in varying animal species.
• The examined model compounds for this study were passively absorbed, high permeability drugs, namely acetaminophen and ketoprofen.
• Additional aspects of the study included electrophysiological measurements and histological examination of tissue samples before and after the test.

Key Findings

• Returns indicated that permeability coefficients were low and inconsistent in both turkey and dog jejunum due to the fragility of the tissue.
• The fragility of the tissues was possibly due to the varying thickness of remaining intestinal layers post-stripping, which in turn caused significant damage.
• In contrast, the small intestines of pigs and horses were considerably more suitable for these permeability determinations, with only mild signs of deterioration observed after an incubation period of two hours (120 minutes).

Electrophysiological Measurements

• There was a lack of correlation between transepithelial electrical resistance and potential difference with the observed tissue damage.

Conclusions

• From the collected data, it appears that the Ussing chamber technique is suitable for permeability measurements within a single species.
• However, the method seems to have limitations when comparing permeability between different animal species.
• The researchers concluded that further verification of the process is necessary, particularly with low permeability compounds and compounds that are actively transported.