Skip to main content
PMC home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1966 Dec;187(3):631–644. doi: 10.1113/jphysiol.1966.sp008114

The potential and short-circuit current across isolated rumen epithelium of the sheep

H G Ferreira, F A Harrison, R D Keynes
PMCID: PMC1395948  PMID: 16783917

Abstract

1. A technique is described for working with isolated sheets of rumen epithelium. Epithelium was obtained at operations for rumen fistulation or in acute experiments and was rapidly mounted between two cone-shaped chambers each of which held 40 ml. of bathing fluid. The fluids were gassed with 95% O2/5% CO2 and 20 cm2 of epithelium was exposed to the fluids.

2. Electrical measurements were made of (a) the potential generated across the epithelium, (b) the short-circuit current which flowed and (c) the resistance of the epithelium.

3. The results are grouped according to the composition of the sheep Ringer solution used to bathe the epithelium. The most stable preparation was obtained when the solutions contained 5 mM each of glucose, acetate, propionate and butyrate as well as bicarbonate and phosphate buffers.

4. In Cl- media, the average initial p.d., short-circuit current (s.-c.c.) and resistance were 9·3 mV, 11·6 μA/cm2 and 1156 Ω. cm2 respectively. Higher values of 17·6 mV, 17·3 μA/cm2 and 1501 Ω. cm2 were recorded in SO42- media. In both media, the s.-c.c. declined at approximately 1·5 μA/cm2.hr and preparations were suitable for study over periods from 4 to 6 hr.

5. When the concentration of potassium was varied on either side of the epithelium at constant [Na+], the potential showed a linear relation with log [K+] for both sides of the epithelium.

6. Changing the sodium concentrations at constant [K+] on either side of the epithelium caused negligible alterations in the potential.

7. Exclusion of sodium from the media bathing both sides of the epithelium abolished the potential and s.-c.c.

8. The addition of ouabain to the blood side of the preparation abolished the potential and s.-c.c. whereas on the rumen side these parameters were unaffected.

Full text

PDF
631

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. ANNISON E. F., PENNINGTON R. J. The metabolism of short-chain fatty acids in the sheep. III Formic, eta-valeric and some branched-chain acids. Biochem J. 1954 Aug;57(4):685–692. doi: 10.1042/bj0570685. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. ARMSTRONG D. G., BLAXTER K. L., GRAHAM N. M. The heat increments of mixtures of steam-volatile fatty acids in fasting sheep. Br J Nutr. 1957;11(4):392–408. doi: 10.1079/bjn19570061. [DOI] [PubMed] [Google Scholar]
  3. ASH R. W., DOBSON A. THE EFFECT OF ABSORPTION ON THE ACIDITY OF RUMEN CONTENTS. J Physiol. 1963 Nov;169:39–61. doi: 10.1113/jphysiol.1963.sp007240. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. DOBSON A. Active transport through the epithelium of the reticulo-rumen sac. J Physiol. 1959 May 19;146(2):235–251. doi: 10.1113/jphysiol.1959.sp006191. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. FORTE J. G., DAVIESRE Oxygen consumption and active transport of ions by isolated frog gastric mucosa. Am J Physiol. 1963 May;204:812–816. doi: 10.1152/ajplegacy.1963.204.5.812. [DOI] [PubMed] [Google Scholar]
  6. Ferreira H. G., Harrison F. A., Keynes R. D., Nauss A. H. Observations on the potential across the rumen of the sheep. J Physiol. 1966 Dec;187(3):615–630. doi: 10.1113/jphysiol.1966.sp008113. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Hird F. J., Weidemann M. J. Transport and metabolism of butyrate by isolated rumen epithelium. Biochem J. 1964 Sep;92(3):585–589. doi: 10.1042/bj0920585. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. MASSON M. J., PHILLIPSON A. T. The absorption of acetate, propionate and butyrate from the rumen of sheep. J Physiol. 1951 Apr;113(2-3):189–206. doi: 10.1113/jphysiol.1951.sp004565. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. PENNINGTON R. J., SUTHERLAND T. M. The metabolism of short-chain fatty acids in the sheep. IV. The pathway of propionate metabolism in rumen epithelial tissue. Biochem J. 1956 Aug;63(4):618–628. doi: 10.1042/bj0630618. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. PENNINGTON R. J. The metabolism of short-chain fatty acids in the sheep. I. Fatty acid utilization and ketone body production by rumen epithelium and other tissues. Biochem J. 1952 May;51(2):251–258. doi: 10.1042/bj0510251. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. PENNINGTON R. J. The metabolism of short-chain fatty acids in the sheep. II. Further studies with rumen epithelium. Biochem J. 1954 Mar;56(3):410–416. doi: 10.1042/bj0560410. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. STEVENS C. E. TRANSPORT OF SODIUM AND CHLORIDE BY THE ISOLATED RUMEN EPITHELIUM. Am J Physiol. 1964 May;206:1099–1105. doi: 10.1152/ajplegacy.1964.206.5.1099. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Physiology are provided here courtesy of The Physiological Society

RESOURCES