Effects of tributyltin compounds on ionic regulation and gill ATPase activity in estuarine fish

1989 ◽  
Vol 92 (1) ◽  
pp. 125-129 ◽  
Author(s):  
Alfred E. Pinkney ◽  
David A. Wright ◽  
Michael A. Jepson ◽  
David W. Towle
Keyword(s):  
Atpase Activity ◽  
Estuarine Fish ◽  
Ionic Regulation

Down, up, down and “smolting” twice? Seasonal movement patterns by juvenile steelhead (Oncorhynchus mykiss) in a coastal watershed with a bar closing estuary

2011 ◽  
Vol 68 (8) ◽  
pp. 1341-1350 ◽  
Author(s):  
Sean A. Hayes ◽  
Morgan H. Bond ◽  
Chad V. Hanson ◽  
Andrew W. Jones ◽  
Arnold J. Ammann ◽  
...  
Keyword(s):  
Atpase Activity ◽  
Oncorhynchus Mykiss ◽  
Fork Length ◽  
Estuarine Fish ◽  
Activity Levels ◽  
Winter Storms ◽  
Coastal Watershed ◽  
Seasonal Movement ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Estuarine Water Quality

We investigated emigration behavior, habitat use, and Na+,K+-ATPase activity levels of juvenile steelhead trout (sea-run rainbow trout; Oncorhynchus mykiss ) in Scott Creek, a small coastal watershed with a seasonally closed estuary in central California, USA. Migratory fish moved downstream in the spring with elevated Na+,K+-ATPase activity levels. Larger fish (>150 mm) moved downstream during February and March, leaving the stream, whereas fish moving between April and June were typically smaller and tended to recruit to the estuary. The Na+,K+-ATPase activity levels of estuarine fish varied during the summer as a function of salinity and temperature, but overall levels declined from peak spring values. Many summer recruits were observed retreating upstream into the watershed when estuarine water quality declined in the fall. Rather than entering the ocean when winter storms reconnected the estuary with the ocean in early winter, many migrated downstream several months later during subsequent springs. The largest smolts observed (>190 mm fork length (LF)) were primarily those that had reared in the estuary the previous summer. Smolts were observed making a single migration from the upper watershed, but they were smaller (~120–190 mm LF) with potentially reduced marine survival. In summary, we observed fish moving between freshwater and estuarine habitats seasonally and adjusting their osmoregulatory physiology as needed.

scholarly journals MODULATION OF SCREENING-PIGMENT POSITION IN CRAYFISH PHOTORECEPTORS BY SEROTONIN: POSSIBLE INVOLVEMENT OF Na+/K+-ATPase ACTIVITY

1989 ◽  
Vol 143 (1) ◽  
pp. 459-473
Author(s):  
EUGENIO FRIXIONE ◽  
JORGE HERNÁNDEZ
Keyword(s):  
Atpase Activity ◽  
Membrane Fraction ◽  
Serotonin Antagonists ◽  
Ionic Regulation ◽  
Transport Mechanisms ◽  
Simultaneous Addition ◽  
Screening Pigment ◽  
Stimulation Of

The possibility that serotonin might play a role in the modulation of screening-pigment position in crayfish photoreceptors was explored through experiments with isolated eyes and a membrane fraction from retinal homogenates. In the isolated eye serotonin (≥10−4 moll−1) and some of its agonists exerted a limited dark-adapting influence over the pigment position, irrespective of the presence or absence of light, and this effect was abolished by the simultaneous addition of serotonin antagonists. In the retinal membrane fraction serotonin and quipazine produced a methysergide-sensitive stimulation of the Na+/K+-ATPase activity. These results are interpreted in terms of a serotonin-mediated efferent input on the photoreceptors, which would affect the ionic regulation of the pigment transport mechanisms.

Sign in / Sign up

Export Citation Format

Share Document