Abstract
Certain euryhaline teleosts can tolerate media of very high salinity, i.e. greater than that of seawater itself. The osmotic gradient across the integument of these fish is very high and the key to their survival appears to be the enhanced ability of the gill to excrete excess NaCl. These fish provide an opportunity to study morphological and biochemical aspects of transepithelial salt secretion under conditions of vastly different transport rates. Since the cellular site of gill salt excretion is believed to be the "chloride cell" of the branchial epithelium and since the enzyme Na,K-ATPase has been implicated in salt transport in this and other secretory tissues, we have focused our attention on the differences in chloride cell structure and gill ATPase activity in the variegated pupfish Cyprinodon variegatus adapted to half-strength seawater (50% SW), seawater (100% SW), or double-stregth seawater (200% SW). The Na,K-ATPase activity in gill homogenates was 1.6 times greater in 100% SW. When 50% SW gills were compared to 100% SW gills, differences in chloride cell morphology were minimal. However, chloride cells from 200% SW displayed a marked hypertrophy and a striking increase in basal-lateral cell surface area. These results suggest that there are correlations among higher levels of osmotic stress, basal-lateral extensions of the cell surface, and the activity of the enzyme Na,K-ATPase.
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- Butler D. G., Carmichael F. J. (Na + -K + )-ATPase activity in eel (Anguilla rostrata) gills in relation to changes in environmental salinity: role of adrenocortical steroids. Gen Comp Endocrinol. 1972 Dec;19(3):421–427. doi: 10.1016/0016-6480(72)90241-9. [DOI] [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]
- Ernst S. A., Ellis R. A. The development of surface specialization in the secretory epithelium of the avian salt gland in response to osmotic stress. J Cell Biol. 1969 Feb;40(2):305–321. doi: 10.1083/jcb.40.2.305. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ernst S. A., Goertemiller C. C., Jr, Ellis R. A. The effect of salt regimens on the development of (Na+K+)-dependent ATPase activity during the growth of salt glands of ducklings. Biochim Biophys Acta. 1967 Sep 9;135(4):682–692. doi: 10.1016/0005-2736(67)90098-3. [DOI] [PubMed] [Google Scholar]
- Fletcher G. L., Stainer I. M., Holmes W. N. Sequential changes in the adenosinetriphosphatase activity and the electrolyte excretory capacity of the nasal glands of the duck (Anas platyrhynchos) during the period of adaptation to hypertonic saline. J Exp Biol. 1967 Dec;47(3):375–391. doi: 10.1242/jeb.47.3.375a. [DOI] [PubMed] [Google Scholar]
- Kamiya M. Sodium-potassium-activated adenosinetriphosphatase in isolated chloride cells from eel gills. Comp Biochem Physiol B. 1972 Nov 15;43(3):611–617. doi: 10.1016/0305-0491(72)90145-9. [DOI] [PubMed] [Google Scholar]
- Karnaky K. J., Jr, Kinter L. B., Kinter W. B., Stirling C. E. Teleost chloride cell. II. Autoradiographic localization of gill Na,K-ATPase in killifish Fundulus heteroclitus adapted to low and high salinity environments. J Cell Biol. 1976 Jul;70(1):157–177. doi: 10.1083/jcb.70.1.157. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Keys A., Willmer E. N. "Chloride secreting cells" in the gills of fishes, with special reference to the common eel. J Physiol. 1932 Nov 5;76(3):368–378.2. doi: 10.1113/jphysiol.1932.sp002932. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- Maetz J., Bornancin M. Biochemical and biophysical aspects of salt excretion by chloride cells in teleosts. Fortschr Zool. 1975;23(2-3):322–362. [PubMed] [Google Scholar]
- Maetz J., Skadhauge E. Drinking rates and gill ionic turnover in relation to external salinities in the eel. Nature. 1968 Jan 27;217(5126):371–373. doi: 10.1038/217371a0. [DOI] [PubMed] [Google Scholar]
- Martin B. J., Philpott C. W. The adaptive response of the salt glands of adult mallard ducks to a salt water regime: an ultrastructural and tracer study. J Exp Zool. 1973 Nov;186(2):111–122. doi: 10.1002/jez.1401860202. [DOI] [PubMed] [Google Scholar]
- Maunsbach A. B. The influence of different fixatives and fixation methods on the ultrastructure of rat kidney proximal tubule cells. I. Comparison of different perfusion fixation methods and of glutaraldehyde, formaldehyde and osmium tetroxide fixatives. J Ultrastruct Res. 1966 Jun;15(3):242–282. doi: 10.1016/s0022-5320(66)80109-0. [DOI] [PubMed] [Google Scholar]
- Motais R., Garcia-Romeu F. Transport mechanisms in the teleostean gill and amphibian skin. Annu Rev Physiol. 1972;34:141–176. doi: 10.1146/annurev.ph.34.030172.001041. [DOI] [PubMed] [Google Scholar]
- Neutra M., Leblond C. P. Synthesis of the carbohydrate of mucus in the golgi complex as shown by electron microscope radioautography of goblet cells from rats injected with glucose-H3. J Cell Biol. 1966 Jul;30(1):119–136. doi: 10.1083/jcb.30.1.119. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Oschman J. L., Berridge M. J. Structural and functional aspects of salivary fluid section in Calliphora. Tissue Cell. 1970;2(2):281–310. doi: 10.1016/s0040-8166(70)80021-0. [DOI] [PubMed] [Google Scholar]
- PETERSON M. R., LEBLOND C. P. UPTAKE BY THE GOLGI REGION OF GLUCOSE LABELED WITH TRITIUM IN THE 1 OR 6 POSITION, AS AN INDICATOR OF SYNTHESIS OF COMPLEX CARBOHYDRATES. Exp Cell Res. 1964 Apr;34:420–423. doi: 10.1016/0014-4827(64)90381-7. [DOI] [PubMed] [Google Scholar]
- PHILPOTT C. W., COPELAND D. E. FINE STRUCTURE OF CHLORIDE CELLS FROM THREE SPECIES OF FUNDULUS. J Cell Biol. 1963 Aug;18:389–404. doi: 10.1083/jcb.18.2.389. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Parry G. Osmotic adaptation in fishes. Biol Rev Camb Philos Soc. 1966 Aug;41(3):392–444. doi: 10.1111/j.1469-185x.1966.tb01499.x. [DOI] [PubMed] [Google Scholar]
- Potts W. T., Evans D. H. Sodium and chloride balance in the killifish Fundulus heteroclitus. Biol Bull. 1967 Oct;133(2):411–425. doi: 10.2307/1539836. [DOI] [PubMed] [Google Scholar]
- Potts W. T., Foster M. A., Rudy P. P., Howells G. P. Sodium and water balance in the cichlid teleost, Tilapia mossambica. J Exp Biol. 1967 Dec;47(3):461–470. doi: 10.1242/jeb.47.3.461. [DOI] [PubMed] [Google Scholar]
- REYNOLDS E. S. The use of lead citrate at high pH as an electron-opaque stain in electron microscopy. J Cell Biol. 1963 Apr;17:208–212. doi: 10.1083/jcb.17.1.208. [DOI] [PMC free article] [PubMed] [Google Scholar]
- STEEN J. B., KRUYSSE A. THE RESPIRATORY FUNCTION OF TELEOSTEAN GILLS. Comp Biochem Physiol. 1964 Jun;12:127–142. doi: 10.1016/0010-406x(64)90168-9. [DOI] [PubMed] [Google Scholar]
- Sargent J. R., Thomson A. J., Bornancin M. Activities and localization of succinic dehydrogenase and Na-+/K-+-activated adenosine triphosphatase in the gills of fresh water and sea water eels (Anguilla anguilla). Comp Biochem Physiol B. 1975 May 15;51(1):75–79. doi: 10.1016/0305-0491(75)90362-4. [DOI] [PubMed] [Google Scholar]