A cycle for 45calcium uptake in the rainbow trout, Salmo gairdneri

1985 ◽  
Vol 63 (12) ◽  
pp. 2778-2779 ◽  
Author(s):  
G. F. Wagner ◽  
M. Hampong ◽  
D. H. Copp
Keyword(s):  
Rainbow Trout ◽  
Salmo Gairdneri ◽  
Cyclical Pattern ◽  
Ca Uptake ◽  
Different Populations ◽  
Two Populations ◽  
45Calcium Uptake

The rate of in vivo 45Ca uptake was monitored twice weekly over a period of 9 weeks in two different populations of rainbow trout fry. The rate of uptake cycled approximately every 11 days and the two populations appeared to be in synchrony regarding this cycle. The results are discussed in relation to the cyclical pattern of growth exhibited by salmonids.

Effects of epinephrine on branchial non-electrolyte permeability in rainbow trout

1978 ◽  
Vol 74 (1) ◽  
pp. 227-237 ◽  
Author(s):  
J. Isaia ◽  
J. Maetz ◽  
G. P. Haywood
Keyword(s):  
Rainbow Trout ◽  
Beta Blocker ◽  
Transport Mechanism ◽  
Constant Pressure ◽  
Salmo Gairdneri ◽  
Permeability Coefficients ◽  
Lipophilic Substance ◽  
Hydrophilic Solutes ◽  
Bulk Transport

Using isolated heads perfused at constant pressure, at rates close to those occurring in vivo, the permeability of the gills of the trout Salmo gairdneri to a range of solutes was measured. Under epinephrine-free conditions, butanol and water showed similar high branchial permeability coefficients. Urea, inulin and dextrans (mol. wt 3000 and 20 000) were 7–12 times less permeant, and mannitol 60-70 times less permeant than water or butanol. Epinephrine, at 10(−6) M, greatly increased the permeability of the gills to the small hydrophilic molecules, water and urea, and to the lipophilic substance, butanol, but did not affect the penetration of the large hydrophilic solutes, mannitol, inulin and dextrans. In the presence of 10(−6) M propanolol, a beta-blocker, epinephrine had no effect on the permeation of any of the test substances except that the permeability to urea decreased somewhat. The results suggest that epinephrine increases the permeability of the membranes of the branchial cells but does not affect the permeation of substances that cross the gill walls by paracellular routes or via an intracellular ‘bulk-transport’ mechanism. Such an action would be expected to increase the branchial transfer of oxygen.

scholarly journals Myocardial intracellular pH in a perfused rainbow trout heart during extracellular acidosis in the presence and absence of adrenaline

1986 ◽  
Vol 125 (1) ◽  
pp. 347-359 ◽  
Author(s):  
A. P. Farrell ◽  
C. L. Milligan
Keyword(s):  
Rainbow Trout ◽  
Intracellular Ph ◽  
Ph Regulation ◽  
Respiratory Acidosis ◽  
Mechanical Efficiency ◽  
Extracellular Ph ◽  
Salmo Gairdneri ◽  
Intracellular Ph Regulation ◽  
Extracellular Acidosis

Myocardial intracellular pH was measured in a perfused rainbow trout, Salmo gairdneri, with DMO (5,5-dimethyl-2,4-oxazlidinedione), to test the hypothesis that catecholamines promote active regulation of myocardial pH in order to protect contractility during a respiratory acidosis comparable to that observed after exercise. Under control conditions (extracellular pH = 8.0; PCO2 = 2 Torr), myocardial pH was 7.53 +/− 0.01 (N = 5). Acidosis (extracellular pH = 7.45; PCO2 = 8.6 Torr) reduced contractility, mechanical efficiency and intracellular pH (7.25 +/− 0.04), but did not affect myocardial O2 consumption. The addition of 0.5 mumol l-1 adrenaline during extracellular acidosis prevented the loss of contractility, restored mechanical efficiency, but did not change intracellular pH significantly. Thus, adrenaline enabled cardiac contractility to recover, without intracellular pH regulation, possibly by modulation of sarcolemmal calcium changes. The absence of a myocardial acidosis after exercise in vivo is discussed with respect to possible intracellular pH regulation via lactate uptake and metabolism.

A Study of in vivo Glycine Absorption by Fed and Fasted Rainbow Trout (Salmo Gairdneri)

1981 ◽  
Vol 91 (1) ◽  
pp. 285-292 ◽  
Author(s):  
G. BOGÉ ◽  
A. RIGAL ◽  
G. PÉRES
Keyword(s):  
Body Weight ◽  
Rainbow Trout ◽  
Weight Gain ◽  
Amino Acid ◽  
Acid Concentration ◽  
Dry Weight ◽  
Salmo Gairdneri ◽  
Mucosal Tissue ◽  
Perfusion Technique

The effects of 4 and 8 weeks fasting at 16 °C were studied in rainbow trout, Salmo gairdneri Richardson. After 4 and 8 weeks, the wet weights of the intestine of fasted animals are respectively 64% and 69% lower than those of fed animals. These effects especially concern the mucosal tissue. Glycine absorption (0.5 and 10 mm) was studied using an in vivo perfusion technique. After 4 weeks, the absolute amounts of 0.5 mm glycine absorbed by fasted and fed fish are similar. With 10 mm glycine, the absorption is slightly lower in fasted trout (−19%). After 8 weeks these differences are more marked, with glycine concentrations of 10 mm (−42%). Results expressed per 100 g body weight showed that these differences result partly from a weight gain of fed trout. Absorption expressed in terms of weight of dry intestine is higher in 4 and 8 weeks fasted animals, principally for the lower amino acid concentration (+61% and +111%). Larger differences were apparent when the absorptions were expressed in terms of dry weight of mucosal tissue (+122% and +225%).

Sign in / Sign up

Export Citation Format

Share Document