[Application of a potential difference to evaluate the absorptive faculty in the small intestine. The change of the transmural resistance and the transport system during post-natal development].
Presently there is no effective method for evaluating the intestinal absorption of sugar, amino acid and small peptide. Since the transmural potential difference (delta PD) is generated immediately when sugar, amino acid or small peptide are absorbed in the small intestine, we tried to utilize this potential difference for the evaluation of absorptive faculty. The delta PD is the product of influx and electrical transmural resistance. To evaluate the intestinal absorptive faculty by the delta PD it is necessary that the electrical resistance of the small intestine does not change throughout the life time and that sugars, amino acids and peptides are transported actively. In guinea pig, the electrical resistance of the small intestine was examined in postnatal development in vitro. Transport systems of sugars amino acid and peptide were also investigated. Through the entire life the electrical resistance of the small intestine remained at almost the same value and sugars and amino acid were completely transported actively from the birth. But small peptide was transported actively after the period of weanling. Evaluation of intestinal aborptive faculty of sugars, amino acids and small peptides is considered to be possible by the transmural potential difference.
D000818:Animals; D004553:Electric Conductivity; D004594:Electrophysiology / Q000379:methods; D005947:Glucose / Q000378:metabolism; D005998:Glycine / Q000378:metabolism; D006033:Glycylglycine / Q000378:metabolism; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007408:Intestinal Absorption; D007421:Intestine, Small / Q000254:growth & development* / Q000502:physiology; D007785:Lactose / Q000378:metabolism; D008320:Maltose / Q000378:metabolism
D006033:Glycylglycine; D008320:Maltose; D005947:Glucose; D007785:Lactose; D005998:Glycine