Skip to Main Content
 

Global Search Box

 
 
 
 

ETD Abstract Container

Abstract Header

HEMOGLOBIN SYNTHESIS, FUNCTION AND METABOLISM IN GREYHOUNDS

Zaldivar-Lopez, Sara

Abstract Details

2012, Doctor of Philosophy, Ohio State University, Comparative and Veterinary Medicine.
The Greyhounds’ history as racing sighthounds has resulted in a unique physiology that distinguishes them from other dog breeds. Results of routine clinical pathology tests in retired racing Greyhounds (RRGs) frequently lie outside of the reference ranges for dogs, and many of these peculiarities have also been described in other sighthounds. Iron is necessary in the body for RBC production, but its metabolism has to be tightly regulated because when free and in excess iron is toxic. Most functional iron is found as hemoglobin (Hb). We have investigated iron metabolism in Greyhounds compared to other dog breeds, finding that UIBC and TIBC are lower and %SAT is higher. We also evaluated iron status in current blood donor dogs and effects over time: iron and %SAT are higher and UIBC is lower in blood donors when compared to controls, and over time iron and %SAT decrease and UIBC/TIBC increase. Our canine population donation intensity and iron status is comparable to human “superdonors”. Identification of the biology underlying this has important implications for human medicine. The Hb molecule is formed by symmetric pairing of alpha and beta globin chains into a structural and functional unit with an iron ion (oxygen-binding site). Due to the high prevalence of hemoglobinopathies in people, the alpha- and beta-globin genes of humans, mice, and chickens, are well characterized. However, despite the increasing importance of dog as models for human diseases, almost nothing is known about dog Hb genetics, and it is reported they only have one beta globin gene, and that they lack fetal Hb. Hb in Greyhounds has higher oxygen affinity, better oxygen carrying properties and same 2,3-DPG content than other dog breeds. We have defined the genetics of canine alpha- and beta-globin genes, and discovered several SNPs and haplotypes that could explain the Greyhound-specific Hb properties. Galgos Españoles (Spanish Greyhounds) have also better oxygenation parameters and higher Hb affinity than mixed breed dogs. During intravascular hemolysis, Hb is released into the bloodstream and can cause oxidative damage to the tissues (e.g. hypertension, kidney damage, thrombosis). Haptoglobin (Hp) binds to the free Hb and removes it from circulation. Former racing Greyhounds have low Hp concentration that could partially account for the low α- globulin concentrations in the breed. We have investigated the HP gene in Greyhounds, finding that the gene is expressed in this breed, and it does not have sequence variations that can explain this anhaptoglobinemia. We also found that Galgos Españoles have similar Hp concentrations to non-Greyhound dogs. Overall, the purpose of this thesis is to be a comprehensive investigation of hemoglobin physiology and genetic characterization in Greyhounds, including its synthesis (i.e. iron) and degradation (i.e. haptoglobin). In order to obtain a better understanding, we also studied Hb and Hp in Galgos Españoles because, although registered as a different breed, Galgos Españoles are phenotypically indistinguishable from Greyhounds, with the difference of not being under the strong selection of the racing industry.
C. Guillermo Couto (Advisor)
Carlos E. Alvarez (Advisor)
Maxey L. Wellman (Committee Member)
William C. Kisseberth (Committee Member)
193 p.

Recommended Citations

Citations

  • Zaldivar-Lopez, S. (2012). HEMOGLOBIN SYNTHESIS, FUNCTION AND METABOLISM IN GREYHOUNDS [Doctoral dissertation, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu1338382975

    APA Style (7th edition)

  • Zaldivar-Lopez, Sara. HEMOGLOBIN SYNTHESIS, FUNCTION AND METABOLISM IN GREYHOUNDS. 2012. Ohio State University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu1338382975.

    MLA Style (8th edition)

  • Zaldivar-Lopez, Sara. "HEMOGLOBIN SYNTHESIS, FUNCTION AND METABOLISM IN GREYHOUNDS." Doctoral dissertation, Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1338382975

    Chicago Manual of Style (17th edition)