Effect of pH on the Transport Capacity of Na+ Across the Isolated Omasal and Ruminal Epithelia of Sheep
This study was conducted in attempt to characterize the electroneutral transport of Na+ across isolated omasmal and ruminal epithelia of sheep after treatment with pH and amiloride. The conventional Ussing chamber technique was used to measure the mucosal to serosal flux (Jms), the serosal to mucosal flux (Jsm), the net flux (Jnet), the short circuit current (Isc), and tissue conductance (Gt) of isolated epithelia. A total of 12 pairs of omasmal and ruminal epithelia were used for each treatment, which categorized as: control group (pH 7.4), low pH group (pH 6.4), amiloride group (pH 7.4) and amiloride + low pH group (pH 6.4). The unidirectional transport values of Na+ were significantly (p<0.001) higher in the omasum compared to the rumen. Lowering the pH to 6.4 significantly (p<0.001) enhanced the unidirectional transport of Na+ in the omasum accompanied by marked changes in the electrochemical parameters (Isc and Gt); however, the enhancement of the unidirectional flux of Na+ in the rumen did not reach the significant level. Application of amiloride in the mucosal side caused a significant (p<0.001) reduction in Jms, Jsm and Jnet of both epithelia. The findings confirmed that Na+ transported by means of electroneutral transport systems in the omasum was similar to the system confirmed previously in the rumen. The electroneutral transport of Na+ in the omasum is more efficient than the that in the rumen.
Aschenbach JR, Penner GB, Stumpff F, Gäbel G. (2011). Ruminant nutrition symposium: Role of fermentation acid absorption in the regulation of ruminal pH. J Anim Sci. 89:1092-1107.
Biber TU and Mullen TL. (1976). Saturation kinetics of sodium efflux across isolated frog skin. Am. J. Physiol. 231(4): 995-1001.
Busche B, Bartels J, Genz AK and von Engelhardt W. (1997). Effect of SCFA on intracellular pH and intracellular pH regulation of guinea-pig caecal and colonic enterocytes and of HT29-19a monolayers. Comp Biochem Physiol A 118: 395-398.
Chien WJ, Stevens CE. (1972). Coupled active transport of Na and CI across forestomach epithelium. Am J Physiol. 223:997-1003.
Diernaes L, Sehested J, Moller PD and Skadhauge E. (1994). Sodium and chloride transport across the rumen epithelium of cattle in vitro: effect of short-chain fatty acids and amiloride. Experimental Physiology. 79: 755–762.
Dobson A. (1959) Active transport through the epithelium of the reticulo-rumen sac. J Physiol. 146: 235-251.
Edrise BM, Smith RH and Hewitt D. (1986). Exchange of water and certain water-soluble minerals during passage of digesta through the stomach compartments of young ruminanting bovines. Br. J. Nutr. 55: 157-167.
Ferreira HG, Harrison FA, Keynes RD and Zurich L. (1972). Ion transport across an isolated preparation of sheep rumen epithelium. J. Physiol. 222:77–93.
Frizzell RA, Koch MJ and Schultz SG. (1976). Ion transport by rabbit colon. I. Active and passive components. J. Membr. Biol. 27(3): 297-316.
Gäbel G and Martens H. (1991). Transport of Na and Cl across forestomach epithelium: mechanisms and interactions with short-chain fatty acids. In: Tsuda T, Sasaki Y and Kawashima R (editors). Physiological Aspects of Digestion and Metabolism in Ruminants. Orlando, Florida: Academic Press, pp. 129–151.
Gäbel G, Smith E, Martens H. (1988). Stimulation of rumen Na absorption by short chain fatty acids. Pfltigers Arch (Suppl. 1) 411:R107.
Gäbel G, Müller F, Pfannkuche H and Aschenbach JR. (2001). Influence of isoform and DNP on butyrate transport across the sheep ruminal epithelium. J. Comp. Physiol. B 171:215–221.
Gäbel G, Aschenbach JR and Müller F. (2002). Transfer of energy substrates across the ruminal epithelium: Implications and limitations. Anim. Health Res. Rev. 3:15–30.
Harrison FA, Keynes RD, Rankin JC and Zurich L. (1975). The effect of ouabain on ion transport across isolated sheep rumen epithelium. J. Physiol. 249: 669-677.
Knickelbein RG, Aronson PS and Dobbins JW. (1990). Characterization of Na+/H+ exchangers on villus cells in rabbit ileum. Am J Physiol 259: G802-G806.
Kramer T, Michelberger T, Gürtler H, Gäbel G. (1996). Absorption of short-chain fatty acids across ruminal epithelium of sheep. J Comp Physiol B. 166:262-69.
Martens H and Hammer U. (1981). Absorption von Natrium und Magnesium aus dem vorubergehend isolierten Pensen von Schafen wahrend intrravenoser Infusion von Aldosteron. Dtsch. Tierarztl. Wschr. 88: 404-407.
Martens H and Blume I. (1987). Studies on the absorption of sodium and chloride from the rumen of sheep. Comp. Biochem. Physiol. A 86: 653-656.
Martens H and Gäbel G. (1988). Transport of Na and Cl across the epithelium of ruminant fore stomachs: rumen and omasum. A review. Comparative Biochemistry and Physiology. A 90: 569–575.
Martens H and Schweigel M. (2000). Pathophysiology of grass tetany and other hypomagnesuim implications for clinical management. Vet. Clin. North Am. Food Anim. Pract. 16(2): 339-368.
Martens H, Krutzfeld T and Wolf K. (2004). Sodium transport across the isolated epithelium of sheep omasum is influenced by luminal ammonia. J. Vet. Med. A Physiol. Pathol. Clin. Med. 51(2): 46-51.
Montrose MH and Chu S. (1997). Transepithelial SCFA gradients regulate polarized Na/H exchangers and pH microdomains in colonic epithelia. Comp Biochem Physiol A 118: 389-393
Schultheiss G and Martens H. (1999). Ca-sensetive Na transport in sheep omasum. Am. J. Physiol. 276(39): G1331-G1344.
Sehested J, Diernaes L, Moller PD and Skadhauge E. (1996). Transport of sodium across the isolated bovine rumen epithelium: interaction with short-chain fatty acids, chloride and bicarbonate. Experimental Physiology. 81: 79–94.
Shen Z, Seyfert HM, Lhrke B, Schneider F, Zitnan R, Chudy A., Kuhla S, Hammon HA, Blum JW, Martens H, Hagemeister H and Voigt J. (2004). An energy-rich diet causes rumen papillae proliferation associated with more IGF type 1 receptors and increased plasma IGF-1 concentrations in young goats. J. Nutr. 134:11–17.
Vilella S, Guerra L, Helmle-Kolb C and Murer H. (1992). Characterization of basolateral Na/H exchange (Na/H-1) in MDCK cells. Pflugers Arch 420: 275-280.
Von Engelhardt W, Burmester M, Hansen K, Becker G, Rechkemmer G. (1993). Effects of amiloride and ouabain on short-chain fatty acid transport in guinea-pig large intestine. J Physiol. 460:455- 66.
Von Engelhardt W and Hauffe R. (1975). Role of the omasum in absorption and secretion of water and electrolytes in sheep and goats. Page 216 in Digestion and Metabolism in the Ruminant. I. W. McDonald and A. C. I. Warner, ed. Univ. New England Publ. Unit, Armidale, New South Wales, Australia.
- There are currently no refbacks.
U. of K. J. Vet. Med. Anim. Prod.