Absorption of folic acid by everted segments of rat jejunum.

The Journal of physiology ·Vol. 236 ·No. 3 ·1974-02-00 ·Pages 653-61

Blair JA, Johnson IT, Matty AJ

Abstract

1. Everted rings of rat intestine were used to study the initial uptake rate of folic acid at various concentrations and incubation temperatures in vitro.2. Folic acid was accumulated linearly for periods of at least 30 min.3. The initial uptake rate was found to reach a constant value as the concentration of folic acid in the incubation medium was increased above 5 x 10(-6)M.4. Reducing the temperature of incubation from 37 to 27 degrees C gave small Q(10) values at either end of the concentration range.5. Transfer of folic acid into the serosal compartment of everted sacs was shown to undergo a rate reduction in the same concentration range.6. A mechanism for folic acid transport is suggested in which folic acid is converted to the neutral species at the mucosal surface in an acid microclimate.

MeSH Terms

Animals Biological Transport, Active Carbon Radioisotopes Folic Acid/metabolism In Vitro Techniques Intestinal Absorption Intestinal Mucosa/metabolism Jejunum/metabolism Male Rats Temperature Time Factors

Chemicals

Carbon Radioisotopes Folic Acid

Authors & Affiliations

3 authors, click to expand affiliations / ORCID

Blair J A

Johnson I T

Matty A J

References (16)

16 references, click to expand

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Article Info

Journal

The Journal of physiology

Abbr.

J Physiol

ISSN

0022-3751

DOI

10.1113/jphysiol.1974.sp010458

Published

1974-02-00

Pages

653-61

Language

English

Region

England

NLM ID

0266262

PMCID

PMC1350855

Subset

External Links

PubMed source DOI: 10.1113/jphysiol.1974.sp010458 PMC Full Text View journal details

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Absorption of folic acid by everted segments of rat jejunum.

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