Biol. Bull. Sign up for etocs!
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Wright, D. A.
Right arrow Articles by Purcell, J. E.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Wright, D. A.
Right arrow Articles by Purcell, J. E.

The Biological Bulletin, Vol 192, Issue 2 332-339, Copyright © 1997 by Marine Biological Laboratory

PHYSIOLOGY

Effect of Salinity on Ionic Shifts in Mesohaline Scyphomedusae, Chrysaora quinquecirrha

D. A. Wright and J. E. Purcell
University of Maryland System, Center for Environmental and Estuarine Studies, Chesapeake Biological Laboratory, Solomons, Maryland 20688-0038

Mesohaline populations of the scyphomedusae Chrysaora quinquecirrha are found in salinities ranging from 5{permill} to 25{permill}. Osmotic and ionic adjustments within this salinity range were investigated using C. quinquecirrha ephyrae budded from polyps in the laboratory and young medusae collected from the mid-salinity region of the Patuxent River, Maryland. When medusae were transferred from 20{permill} salinity to lower salinities (8{permill}, 12{permill}), concentrations of sodium and magnesium in tissue and mesogleal fluid fell rapidly and approached those of dilute seawater within 6 hours. There was some recovery of these levels relative to the 8{permill} medium, and they were significantly higher than the dilute seawater concentration after 1 week. Tissue concentrations of calcium showed no evidence of being regulated, whereas potassium was strongly regulated such that levels did not fall significantly following transfer of medusae to lower salinities. However, after 1 week, the concentration of potassium in mesogleal fluid approached that of the dilute medium. Extracellular space measured by direct blotting and weighing or using 35S was about 40%. As a result, estimates for intracellular potassium were revised to 17 mM1-1. The concentration of potassium in tissue remained stable following transfer to lower salinity, despite a substantial osmotic influx of water. This influx was measured as a >20% gain in body weight over 24 h following transfer of medusae from 16{permill} to 8{permill}. Mesogleal fluid was slightly hypo-osmolar to the medium at 15% and 20{permill} and slightly hyperosmolar to the medium at 5{permill} and 12{permill}. Sulfate concentrations in mesogleal fluid were 66%-70% those of the external medium. Medusae died or were unable to achieve positive buoyancy at 5%{permill}, which is probably very close to a lower salinity limit for C. quinquecirrha in the mesohaline Chesapeake Bay.


This article has been cited by other articles:


Home page
 J. Exp. Biol.Home page
E. V. Thuesen, L. D. Rutherford Jr, P. L. Brommer, K. Garrison, M. A. Gutowska, and T. Towanda
Intragel oxygen promotes hypoxia tolerance of scyphomedusae
J. Exp. Biol., July 1, 2005; 208(13): 2475 - 2482.
[Abstract] [Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
V. Pierce, L. Mueller, and A. Gibbs
Osmoregulation in Drosophila melanogaster selected for urea tolerance
J. Exp. Biol., January 9, 1999; 202(17): 2349 - 2358.
[Abstract] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1997 by the Marine Biological Laboratory.