Glucose uptake and glucose transporters in the rainbow trout (Oncorhynchus mykiss) ventricle.

More About This Textbook


My dissertation examines glucose uptake and glucose transporters in a novel experimental model: male and female rainbow trout (Oncorhynchus mykiss) ventricles. One of the questions that I addressed was the effect of hypoxia on glucose uptake. It has been shown in both mammalian striated muscle and fish cardiac muscle that hypoxia can increase glucose uptake via GLUT type glucose transport proteins. Given the structure of the rainbow trout cardiovascular system and the potential for low oxygen levels in its environment, we hypothesized that hypoxia may stimulate glucose uptake. We addressed this question using the glucose analog 2-deoxyglucose (2-DG) to measure the uptake of glucose into the ventricle tissue. These experiments also incorporated cytochalasin B (CB), a specific GLUT type glucose transporter inhibitor. Interestingly, CB significantly decreased glucose uptake approx. 60% (P < 0.001), however hypoxia did not increase glucose uptake above the oxygenated controls. Additional experiments showed that hypoxia increased lactate efflux approx. five-fold (P < 0.001) over oxygenated controls. Interestingly, both glycogen and free glucose were significantly less in males (P < 0.0001; n = 3-5 for each sex) for all conditions with no treatment effects found in the 2-way ANOVA analysis. The results from the 2-DG uptake experiments with CB supported the existence of GLUT type glucose transporter proteins in the ventricle tissue. In order to verify this, we commissioned the production of a specific GLUT transporter protein antibody and probed for GLUT type transporters in the rainbow trout ventricle. Our Western Blots did indeed demonstrate GLUT1 and GLUT4 type glucose transport proteins in both male and female rainbow trout ventricle tissue just below a molecular weight of 50 kD. Given that our model expressed GLUTs but did not increase glucose uptake in response to hypoxia, we followed with several experiments designed to better define glucose uptake kinetics in the rainbow trout ventricle. Here we show that only high (100 mM and 50 mM) D-glucose competitively inhibits 2-DG uptake significantly (P < 0.001 and P < 0.05, respectively). Data from 2-DG Concentration-response assay (1mM and 40 mM) was evaluated with the Michaelis-Menten equation and fit a rectangular hyperbola. However, calculated Km was extrapolated beyond concentrations used in the assay. When temperature is decreased from 14°C to 4°C, total and GLUT mediated 2-DG uptake is decreased 51 +/- 6.5% (P < 0.001; n=6) and 31 +/- 20% (P < 0.05; n = 6) respectively, consistent with a facilitated diffusion model. The decrease in 2-DG uptake xvi between 24°C and 4°C was significant with CB (65 +/- 5.3%; P < 0.01; n = 6); without CB (51 +/- 6.5%; P < 0.001; n = 6); and in the GLUT mediated fraction (31 +/- 20%; P < 0.05; n = 6). Taken together, we conclude that glucose enters rainbow trout ventricle tissue by a combination of facilitated diffusion via GLUTs and another, yet to be identified route. Additionally, our findings support that the rainbow trout ventricle GLUT transporters are regulated differently than those found in mammalian and some other fish models. These novel findings expand our understanding of the variety of glucose transporter function and glucose uptake in a non-pathological, non-mammalian model. (Abstract shortened by UMI.)
Read More Show Less

Product Details

  • BN ID: 2940032471066
  • Publisher: ProQuest LLC
  • Sold by: Barnes & Noble
  • Format: eTextbook
  • Pages: 166

Customer Reviews

Be the first to write a review
( 0 )
Rating Distribution

5 Star


4 Star


3 Star


2 Star


1 Star


Your Rating:

Your Name: Create a Pen Name or

Barnes & Review Rules

Our reader reviews allow you to share your comments on titles you liked, or didn't, with others. By submitting an online review, you are representing to Barnes & that all information contained in your review is original and accurate in all respects, and that the submission of such content by you and the posting of such content by Barnes & does not and will not violate the rights of any third party. Please follow the rules below to help ensure that your review can be posted.

Reviews by Our Customers Under the Age of 13

We highly value and respect everyone's opinion concerning the titles we offer. However, we cannot allow persons under the age of 13 to have accounts at or to post customer reviews. Please see our Terms of Use for more details.

What to exclude from your review:

Please do not write about reviews, commentary, or information posted on the product page. If you see any errors in the information on the product page, please send us an email.

Reviews should not contain any of the following:

  • - HTML tags, profanity, obscenities, vulgarities, or comments that defame anyone
  • - Time-sensitive information such as tour dates, signings, lectures, etc.
  • - Single-word reviews. Other people will read your review to discover why you liked or didn't like the title. Be descriptive.
  • - Comments focusing on the author or that may ruin the ending for others
  • - Phone numbers, addresses, URLs
  • - Pricing and availability information or alternative ordering information
  • - Advertisements or commercial solicitation


  • - By submitting a review, you grant to Barnes & and its sublicensees the royalty-free, perpetual, irrevocable right and license to use the review in accordance with the Barnes & Terms of Use.
  • - Barnes & reserves the right not to post any review -- particularly those that do not follow the terms and conditions of these Rules. Barnes & also reserves the right to remove any review at any time without notice.
  • - See Terms of Use for other conditions and disclaimers.
Search for Products You'd Like to Recommend

Recommend other products that relate to your review. Just search for them below and share!

Create a Pen Name

Your Pen Name is your unique identity on It will appear on the reviews you write and other website activities. Your Pen Name cannot be edited, changed or deleted once submitted.

Your Pen Name can be any combination of alphanumeric characters (plus - and _), and must be at least two characters long.

Continue Anonymously

    If you find inappropriate content, please report it to Barnes & Noble
    Why is this product inappropriate?
    Comments (optional)