In vitro study of hepatic iodothyronine deiodination in rainbow trout, Salmo gairdneri

1983 ◽  
Vol 61 (3) ◽  
pp. 547-552 ◽  
Author(s):  
N. J. Pimlott ◽  
J. G. Eales
Keyword(s):  
Rainbow Trout ◽  
Incubation Temperature ◽  
In Vitro Study ◽  
Outer Ring ◽  
Salmo Gairdneri ◽  
Ph Optimum ◽  
Vitro Assay ◽  
Liver Homogenates ◽  
Mammalian Counterpart

A rapid method involving radioiodide separation by miniature G-25 Sephadex columns was used for in vitro assay of outer-ring deiodination of labeled thyroxine ([125I]T4) and 3,5,3′-triiodo-L-thyronine ([125I]T3) by liver homogenates of rainbow trout acclimated at 12 °C. T4 deiodination depended on time, enzyme (protein) level, substrate (T4) level, and pH (optimum, 6.8–7.4). Boiling eliminated deiodination. Over the range 12–20 °C incubation temperature modified both Km and Vmax values but did not alter the pH optimum. Deiodination was accompanied by [125I]T3 production, but 125I-labeled reverse T3 was not detected. T4 deiodination was unaltered by addition of carrier T3 or T3 removal by immunosequestration. T3 itself underwent no outer-ring deiodination at 12 °C and weak deiodination at 20 °C (pH optimum 6.8–7.4). In conclusion, trout liver posseses a T4 5′-monodeiodinase with several properties similar to those of its mammalian counterpart but with little tendency to deiodinate T3.

An In-Vitro Assay Estimating Changes in Melanin Content of Melanoma Cells due to Ultra-Dilute, Potentized Preparations

Homeopathy ◽  
2019 ◽  
Vol 108 (03) ◽  
pp. 183-187 ◽  
Author(s):  
Renuka Munshi ◽  
Samidha Joshi ◽  
Gitanjali Talele ◽  
Rajesh Shah
Keyword(s):  
In Vitro Study ◽  
Melanoma Cells ◽  
Tyrosinase Activity ◽  
Melanin Content ◽  
B16f10 Melanoma ◽  
Vitro Assay ◽  
Melanocyte Stimulating Hormone ◽  
B16f10 Melanoma Cells ◽  
Physiological Dose

Introduction The authors had previously conducted an in-vitro study to observe the effect of homeopathic medicines on melanogenesis, demonstrating anti-vitiligo potential by increasing the melanin content in murine B16F10 melanoma cells. A similar experiment was performed using further homeopathic preparations sourced from kojic acid (KA), hydrogen peroxide (H2O2; HP), 6-biopterin (BP), and [Nle4, D-Phe7]-α-melanocyte-stimulating hormone (NLE), some of which are known to induce vitiligo or melano-destruction at physiological dose. Materials and Methods The homeopathic preparations of BP, KA, NLE, and HP were used in 30c potency. Alcohol and potentized alcohol were used as vehicle controls. Prior to starting the main experiment, the viability of B16F10 melanoma cells after treatment with study preparations was assayed. Melanin content (at 48 h and 96 h) and tyrosinase activity in melanocytes were determined. Results At the end of 48 hours, NLE and HP in 30c potency had a significantly greater melanin content (p = 0.015 and p = 0.039, respectively) compared with controls; BP and KA in 30c potency had no significant effects. No significant changes were seen at the end of 96 hours. KA, NLE, HP, and vehicle controls showed an inhibition of tyrosinase activity. Conclusion The study demonstrated melanogenic effects of two homeopathic preparations. Further research to evaluate the therapeutic efficacy of these medicines is warranted.

Biosynthesis of Lecithin by the CDP-Choline Pathway in Liver Microsomes of Rainbow Trout, Salmo gairdneri

1975 ◽  
Vol 32 (9) ◽  
pp. 1633-1637 ◽  
Author(s):  
B. J. Holub ◽  
K. Nilsson ◽  
J. Piekarski ◽  
S. J. Slinger
Keyword(s):  
Rainbow Trout ◽  
Incubation Medium ◽  
Enzymatic Synthesis ◽  
Environmental Temperature ◽  
Incubation Temperature ◽  
Liver Microsomes ◽  
Salmo Gairdneri ◽  
Optimal Activity

The enzymatic synthesis of lecithin from CDP-choline (14C) was characterized in microsomal preparations from the livers of rainbow trout (Salmo gairdneri). Optimal activity was obtained with the addition of 1,2-digylceride and Mg++ to the incubation medium. There was a 290% stimulation in cholinephosphotransferase activity when the incubation temperature was raised from 15 to 37 C. The results indicate that the CDP-choline pathway is operative in the formation of lecithin in the liver of rainbow trout. The possible function of this reaction in the acclimation offish to environmental temperature is discussed.

scholarly journals Some effects of vitamin E and selenium deprivation on tissue enzyme levels and indices of tissue peroxidation in rainbow trout (Salmo gairdneri)

1985 ◽  
Vol 53 (1) ◽  
pp. 149-157 ◽  
Author(s):  
J. G. Bell ◽  
C. B. Cowey ◽  
J. W. Adron ◽  
Aileen M. Shanks
Keyword(s):  
Rainbow Trout ◽  
Vitamin E ◽  
Peroxidase Activity ◽  
Cumene Hydroperoxide ◽  
Dietary Vitamin ◽  
Salmo Gairdneri ◽  
Deficient Diet ◽  
Exudative Diathesis ◽  
Malondialdehyde Formation

1. Duplicate groups of rainbow trout (Salrno gairdnert) (mean weight 11 g) were given for 40 weeks one of four partially purified diets that were either adequate or low in selenium or vitamin E or both.2. Weight gains of trout given the dually deficient diet were significantly lower than those of trout given a complete diet or a diet deficient in Se. No mortalities occurred and the only pathology seen was exudative diathesis in the dually deficient trout.3. There was significant interaction between the two nutrients both with respect to packed cell volume and to malondialdehyde formation in the in vitro NADPH-dependent microsomal lipid peroxidation system.4. Tissue levels of vitamin E and Se decreased to very low levels in trout given diets lacking these nutrients. For plasma there was a significant effect of dietary vitamin E on Se concentration.5. Glutathione (GSH) peroxidase (EC 1. 1 1. 1.9) activity in liver and plasma was significantly lower in trout receiving low dietary Se but was independent of vitamin E intake. The ratios of hepatic GSH peroxidase activity measured with cumene hydroperoxide and hydrogen peroxide were the same for all treatments. This confirms the absence of a Se-independent GSH peroxidase activity in trout liver.6. Se deficiency did not lead to any compensatory increase in hepatic GSH transferase (EC 2. 5. 1. 18) activity; values were essentially the same in all treatments.7. Plasma pyruvate kinase (EC 2. 7. 1.40) activity increased significantly in the trout deficient in both nutrients. This was thought to be due to leakage of the enzyme from the muscle and may be indicative of incipient (subclinical) muscle damage.

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