Protective effects of calcium against the physiological effects of exposure to a combination of cadmium and copper in rainbow trout (Oncorhynchus mykiss)

1999 ◽  
Vol 77 (7) ◽  
pp. 1035-1047 ◽  
Author(s):  
Jeff G Richards ◽  
Richard C Playle
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Plasma Concentrations ◽  
Lactate Concentration ◽  
Haemoglobin Concentration ◽  
Arterial Oxygen Tension ◽  
Soft Water ◽  
Arterial Oxygen ◽  
Cd Accumulation ◽  
Rainbow Trout Oncorhynchus Mykiss

We report that an elevated aqueous calcium (Ca) concentration protects against acute respiratory and osmoregulatory action due to exposure to a combination of cadmium (Cd) and copper (Cu) in rainbow trout (Oncorhynchus mykiss), but does not protect against longer term ionoregulatory disruption. Trout exposed to 0.18 µM Cd and 0.80 µM Cu in soft water (40 µM Ca, 440 µM Na, pH 6.6) experienced a 60-torr decrease in arterial oxygen tension, a 5.5 mM increase in blood lactate concentration, and severe haemoconcentration as indicated by a 1.4-fold decrease in mean cell haemoglobin concentration, all of which occurred within 24 h. The addition of Ca to soft water (to reach 910 µM Ca, added as CaCl2; 430 µM Na, pH 6.8) eliminated these severe effects and slowed Cd uptake by the gills, plasma, and liver of trout, probably through competition for binding at gill Ca channels, but Ca did not affect Cu uptake by the gills or its entry into the plasma. Associated with slower Cd accumulation and unchanged Cu accumulation in the plasma were slow decreases in plasma concentrations of Na, Cl, and Ca, which were prevented initially by adding Ca to the water. Modelling using a modified aqueous chemistry computer program, MINEQL+, and previously published gill binding constants accurately simulated the initial (18 h) accumulation of Cd and Cu by trout gills and thus predicted acute toxicity, but our model did not adequately simulate the physiological mechanisms of Cd accumulation by trout gills over longer exposures up to 130 h.

scholarly journals EFFECTS OF SEROTONIN ON CIRCULATION AND RESPIRATION IN THE RAINBOW TROUT ONCORHYNCHUS MYKISS

1992 ◽  
Vol 173 (1) ◽  
pp. 59-73 ◽  
Author(s):  
R. Fritsche ◽  
S. Thomas ◽  
S. F. Perry
Keyword(s):  
Blood Pressure ◽  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Plasma Catecholamines ◽  
Arterial Oxygen Tension ◽  
Arterial Oxygen ◽  
Response Analysis ◽  
Plasma Catecholamine ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Pre Treatment

The effects of serotonin (5-hydroxytryptamine; 5-HT) on continuously recorded dorsal and ventral aortic blood pressures, (Pda, Pva), arterial oxygen tension (PaO2), arterial carbon dioxide tension (PaCO2), extracellular pH (pHa), buccal pressure (Pbuccal) and plasma catecholamine levels were investigated in rainbow trout, Oncorhynchus mykiss. Intra-arterial injections of serotonin (50–250 nmol kg-1) caused a rapid decrease in Pda and an increase in Pva, suggesting vasoconstriction of the branchial vasculature. The blood pressure changes were accompanied by a reduction in PaO2 (approximately 3–8 kPa depending on the dose injected), an increase in PaCO2 (approximately 0.03–0.07 kPa) and a decrease in pHa (approximately 0.02–0.12 pH units). These changes, indicative of impaired gas transfer, occurred despite obvious hyperventilation based on measurements of buccal pressure. After pre- treatment with the serotonergic receptor antagonist methysergide, injections of 100 nmol kg-1 serotonin caused an increase in PaO2, a reduction in PaCO2 and an increase in pHa. Methysergide treatment did not affect the usual serotonin-induced hyperventilation or the reduction in Pda but did abolish the rise in Pva; indeed, Pva was lowered significantly by serotonin after methysergide treatment. This reduction in Pva was eliminated by pre-treatment of fish with the combination of methysergide and sotalol (beta-adrenoceptor antagonist), suggesting an adrenergic component to the overall blood pressure response. Analysis of plasma catecholamines after injection of serotonin revealed that high doses (50, 100, 250 nmol kg-1) caused significant increases in concentrations of both noradrenaline and adrenaline. We conclude that the cardio-respiratory effects of exogenous serotonin injections are complex and arise from several integrated responses, including the direct action of serotonin on receptors within the branchial and systemic vasculatures, indirect action on ganglionic receptors, and the stimulation of catecholamine release from adrenergic nerves and/or chromaffin cells.

Physiological Responses of Rainbow Trout (Oncorhynchus mykiss) to Prolonged Exposure to Soft Water

1996 ◽  
Vol 69 (6) ◽  
pp. 1419-1441 ◽  
Author(s):  
S. F. Perry ◽  
S. G. Reid ◽  
E. Wankiewicz ◽  
V. Iyer ◽  
K. M. Gilmour
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Prolonged Exposure ◽  
Physiological Responses ◽  
Soft Water ◽  
Rainbow Trout Oncorhynchus Mykiss

Comparative Pharmacokinetics and Bioavailability of Oxolinic Acid in Channel Catfish (Ictalurus punctatus) and Rainbow Trout (Oncorhynchus mykiss)

1994 ◽  
Vol 51 (5) ◽  
pp. 1205-1211 ◽  
Author(s):  
Kevin M. Kleinow ◽  
Herman H. Jarboe ◽  
Kathy E. Shoemaker ◽  
Kevin J. Greenless
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Ictalurus Punctatus ◽  
Channel Catfish ◽  
Plasma Concentrations ◽  
Oxolinic Acid ◽  
Distribution Data ◽  
Antibacterial Drug ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Elimination Half

The pharmacokinetics, bioavailability, and disposition of oxolinic acid (OA), a quinolone antibacterial drug, were examined in a warmwater (channel catfish (Ictalurus punctatus)) and coldwater fish species (rainbow trout (Oncorhynchus mykiss)). Studies were performed at 24 and 14 °C for catfish and at 14 °C for trout to compare temperature- and species-related differences. Analysis of OA pharmacokinetics when determined by HPLC provided elimination half-life [Formula: see text], volume of distribution (Vss), and clearance (Clb) estimates for 24 °C catfish, 14 °C catfish, and 14 °C trout of 40.9, 69.3, and 81.3 h, 939, 880, and 1817 mL/kg, and 16.3, 8.9, and 16.9 mL∙kg∙h−1, respectively. Following oral administration, OA plasma concentrations peaked between 8 and 24 h for all treatments; however, 14 °C trout and 14 °C catfish sustained peak concentrations for a longer duration than 24 °C catfish. Oral OA bioavailabilities were 56.0, 91.8, and 90.7% for 24 °C catfish, 14 °C catfish, and 14 °C trout, respectively. OA distribution data for muscle of 14 °C catfish demonstrated an inordinately high peak concentration and delayed time to peak relative to other treatments. Elimination half-lives of OA in muscle were 33.1, 54.3, and 141 h for 24 °C catfish, 14 °C catfish, and 14 °C trout, respectively.

Effects of stress on plasma homeostasis, endolymph chemistry, and check formation during otolith growth in rainbow trout (Oncorhynchus mykiss)

2004 ◽  
Vol 61 (7) ◽  
pp. 1247-1255 ◽  
Author(s):  
P Payan ◽  
H De Pontual ◽  
A Edeyer ◽  
G Borelli ◽  
G Boeuf ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Plasma Concentrations ◽  
Growth Stress ◽  
Significant Rise ◽  
External Stress ◽  
Otolith Growth ◽  
Ph Variation ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Different Levels

This is the first study in which the effects of an external stress were analysed at different levels: plasma ho meostasis, endolymph chemistry, and otolith growth. Stress was applied to rainbow trout (Oncorhynchus mykiss) by exposure to Cl2 gas. In the plasma of Cl2-stressed trout, Na+ and Cl– decreased (70 mmol·L–1) and K+ increased (2.0 mmol·L–1), whereas total Ca was unchanged. A slight hypercapny (+2.4 mmHg (1 mmHg = 133.322 Pa)) was observed related to a significant rise (40%) in total CO2 without pH variation. In the endolymph, Na+ and Cl– also decreased, whereas other parameters (K+, PO43–, Mg, and, peculiarly, total Ca) remained stable. The important effect provoked by Cl2 stress in endolymph was an increase of proteins (factor of 2.6) and total CO2 (factor of 3.1) concentrations at the proximal side of the endolymph. The stress induced a decrease in otolith growth rate and produced a discontinuity (check) in the microstructure pattern of the otolith characterized by a large D zone. The variations in the endolymph composition are discussed and we propose that they result not only from changes in plasma concentrations, but also from changes (organic and crystallization) in otolith deposition.

Metabolic Costs and Physiological Consequences of Acclimation to Aluminum in Juvenile Rainbow Trout (Oncorhynchus mykiss). 1: Acclimation Specificity, Resting Physiology, Feeding, and Growth

1994 ◽  
Vol 51 (3) ◽  
pp. 527-535 ◽  
Author(s):  
Rod W. Wilson ◽  
Harold L. Bergman ◽  
Chris M. Wood
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Soft Water ◽  
Negligible Effect ◽  
Whole Body ◽  
Rapid Loss ◽  
Juvenile Rainbow Trout ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Metabolic Costs ◽  
Pronounced Reduction

Juvenile rainbow trout (Oncorhynchus mykiss, 5–13 g) became acclimated (i.e., increased their resistance to lethal Al levels, 162 μg∙L−1, pH 5.2) after only 5 d when exposed to sublethal AS (38 μg∙L−1) in acidified soft water (Na+ = 85, Ca2+ = 28 μEq∙L−1, pH 5.2). Acclimation was associated with reduced ionoregulatory and respiratory disturbances during lethal Al challenge and was maintained for at least 34 d. Acclimation was relatively specific to Al because no consistently improved resistance to lethal Cu (32 μg∙L−1, pH 5.2) was observed. Exposure to sublethal acid alone (pH 5.2) did not result in acclimation to lethal [H+] (pH 4.0) and caused a pronounced reduction in whole-body Na+ and Cl−. Sublethal acid + Al resulted in a more rapid loss of ions than sublethal acid alone over the first 10 d, but both groups subsequently recovered ionoregulatory status after 34 d. Exposure to sublethal acid alone had a negligible effect on feeding or growth. However, growth was impaired by 29% in Al-exposed trout, primarily the result of reduced appetite during the first 10 d. Decreased growth must be considered one of the costs of acclimation during chronic sublethal exposure to Al.

Sign in / Sign up

Export Citation Format

Share Document