Abstract
Ionic lanthanum has been used to study transepithelial ion permeation in in vitro rabbit gallbladder and intestine (ileum) by adding 1 mM La3+ to only the mucosal bathing solution. Transepithelial fluid transport electrical potential differences (p.d.), and resistances were measured. During La3+ treatment the gallbladder's rate of active solute-coupled fluid transport remained constant, the resistance increased, and the 2:1 NaCl diffusion p.d. decreased. Mucosa-to-serosa fluxes of 140La3+ were measured and indicate a finite permeability of the gallbladder to La3+. La3+ also increased the transepithelial resistance and p d. of ileum. Electron microscopic examination of La3+-treated gallbladder showed: (a) good preservation of the fine structure, (b) electron-opaque lanthanum precipitates in almost every lateral intercellular space, most frequently near the apical end of the lateral spaces close to or within the junctional complex, (c) lanthanum among the subjacent muscle and connective tissue layers, and (d) lanthanum filling almost the entire length of so-called "tight" junctions. No observations were made which unequivocally showed the penetration of lanthanum into the gallbladder cells. Electron micrographs of similar La3+-treated ilea showed lanthanum deposits penetrating the junctional complexes. These results coupled with other physiological studies indicate that the low resistance pathway for transepithelial ion permeation in gallbladder and ileum is through the tight junctions A division of salt-transporting epithelia into two main groups, those with "leaky" junctional complexes and those with tight junctional complexes, has been proposed.
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Selected References
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- Bentzel C. J., Parsa B., Hare D. K. Osmotic flow across proximal tubule of Necturus: correlation of physiologic and anatomic studies. Am J Physiol. 1969 Aug;217(2):570–580. doi: 10.1152/ajplegacy.1969.217.2.570. [DOI] [PubMed] [Google Scholar]
- DIAMOND J. M. The mechanism of solute transport by the gall-bladder. J Physiol. 1962 May;161:474–502. doi: 10.1113/jphysiol.1962.sp006899. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DIETSCHY J. M. WATER AND SOLUTE MOVEMENT ACROSS THE WALL OF THE EVERTED RABBIT GALL BLADDER. Gastroenterology. 1964 Oct;47:395–408. [PubMed] [Google Scholar]
- Diamond J. M., Bossert W. H. Standing-gradient osmotic flow. A mechanism for coupling of water and solute transport in epithelia. J Gen Physiol. 1967 Sep;50(8):2061–2083. doi: 10.1085/jgp.50.8.2061. [DOI] [PMC free article] [PubMed] [Google Scholar]
- FARQUHAR M. G., PALADE G. E. Junctional complexes in various epithelia. J Cell Biol. 1963 May;17:375–412. doi: 10.1083/jcb.17.2.375. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Giebisch G., Boulpaep E. L., Whittembury G. Electrolyte transport in kidney tubule cells. Philos Trans R Soc Lond B Biol Sci. 1971 Aug 20;262(842):175–196. doi: 10.1098/rstb.1971.0088. [DOI] [PubMed] [Google Scholar]
- Goodenough D. A., Revel J. P. A fine structural analysis of intercellular junctions in the mouse liver. J Cell Biol. 1970 May;45(2):272–290. doi: 10.1083/jcb.45.2.272. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Martinez-Palomo A., Erlij D., Bracho H. Localization of permeability barriers in the frog skin epithelium. J Cell Biol. 1971 Aug;50(2):277–287. doi: 10.1083/jcb.50.2.277. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Overton J. Localized lanthanum staining of the intestinal brush border. J Cell Biol. 1968 Aug;38(2):447–452. doi: 10.1083/jcb.38.2.447. [DOI] [PMC free article] [PubMed] [Google Scholar]
- PIDOT A. L., DIAMOND J. M. STREAMING POTENTIALS IN A BIOLOGICAL MEMBRANE. Nature. 1964 Feb 15;201:701–702. doi: 10.1038/201701a0. [DOI] [PubMed] [Google Scholar]
- SCHULTZ S. G., ZALUSKY R. ION TRANSPORT IN ISOLATED RABBIT ILEUM. II. THE INTERACTION BETWEEN ACTIVE SODIUM AND ACTIVE SUGAR TRANSPORT. J Gen Physiol. 1964 Jul;47:1043–1059. doi: 10.1085/jgp.47.6.1043. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schatzki P. F. Bile canaliculus and space of Disse. Electron microscopic relationships as delineated by lanthanum. Lab Invest. 1969 Jan;20(1):87–93. [PubMed] [Google Scholar]
- Tormey J. M., Diamond J. M. The ultrastructural route of fluid transport in rabbit gall bladder. J Gen Physiol. 1967 Sep;50(8):2031–2060. doi: 10.1085/jgp.50.8.2031. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wheeler H. O., Ross E. D., King K. K. Effect of carbonic anhydrase inhibitors on isolated rabbit gallbladders. Am J Physiol. 1969 Jan;216(1):175–178. doi: 10.1152/ajplegacy.1969.216.1.175. [DOI] [PubMed] [Google Scholar]
- Wright E. M. The origin of the glucose dependent increase in the potential difference across the tortoise small intestine. J Physiol. 1966 Jul;185(2):486–500. doi: 10.1113/jphysiol.1966.sp007998. [DOI] [PMC free article] [PubMed] [Google Scholar]