Ussing Chambers Technique

H Lennernas, S Nylander, AL Ungell. Jejunal permeability A comparison between the Ussing chamber technique and the single-pass perfusion in humans. Pharm Res 14 667-671, 1997. 

Hosoya K, Kubo H, Natsume H, Sugibayashi K, Morimoto Y (1994) Evaluation of enhancers to increase nasal absorption using Ussing chamber technique. Biol Pharm Bull 17 316-322. 

In an attempt to increase the biorelevance of the Ussing chambers technique even further, the use of simulated intestinal fluids (FaSSIF and FeSSIF) as transport media was recently evaluated [105], However, the potential difference collapsed to zero after 120 min when exposed to FaSSIF solution and permeability for mannitol was increased twofold. Electron micrographs revealed erosion of the villi tips and substantial denudation of the microvilli after exposure of the ileal tissue to FaSSIF and FeSSIF [105],... 

Similar to the PAMPA and the Caco-2 models, the experimental pH of the buffer solution can be changed in the Ussing chambers model. However, it seems that the impact of changing the pH of the mucosal (= apical) buffer solution is lower than for the other two systems [82], This is probably due to the presence of the mucus layer retaining the microclimate pH regardless of the luminal pH using the Ussing chambers technique [82],... 

Bajka BH, Gillespie CM, Steeb CB, Read LC, Howarth GS (2003) Applicability of the Ussing chamber technique to permeability determinations in functionally distinct regions of the gastrointestinal tract in the rat. Scand J Gastroenterol 38 732-741. 

To monitor CFTR activity in HBE cultures, Ussing chamber recording techniques are used (Fig. 7). Like the nasal potential difference recording technique used in vivo, the Ussing chamber technique is an extracellular recording of the membrane potential or short circuit current (Isc) due to ion flux through channels and transporters. To isolate CFTR activity, a basolateral to apical Cl" gradient is established and amiloride is added to block the ep-... 

Tran HTT, Tran PHL, Lee B-J (2009) New findings on melatonin absorption and alterations by pharmaceutical excipients using the Ussing chamber technique with mounted rat gastrointestinal segments. Int J Pharm 378(l-2) 9-16... 

In addition to cell-based models, tissue-based models such as the Ussing chamber technique, the everted gut sac approach, and perfused isolated intestinal segments are also used, but only when it is important to understand the absorption processes in more detail. Unlike Caco-2, tissue-based models have the correct physiological levels of transporters and the presence of an apical mucus layer. Also, in situ and isolated organ perfusion methods exist for the gut, liver, lungs, kidneys, and brain and can provide data not directly obtainable in vitro. The isolated perfused liver is particularly useful since it allows an assessment of first-pass hepatic clearance, the quantitative distribution of metabolites in liver, blood, and bile, the effects of binding to plasma proteins and intracellular sites, and cellular uptake processes. 

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