title: Effects of ovariectomy and intrinsic aerobic capacity on tissue-specific insulin sensitivity.
abstract: High-capacity running (HCR) rats are protected against the early (i.e., ∼ 11 wk postsurgery) development of ovariectomy (OVX)-induced insulin resistance (IR) compared with low-capacity running (LCR) rats. The purpose of this study was to utilize the hyperinsulinemic euglycemic clamp to determine whether 1) HCR rats remain protected from OVX-induced IR when the time following OVX is extended to 27 wk and 2) tissue-specific glucose uptake differences are responsible for the protection in HCR rats under sedentary conditions. Female HCR and LCR rats (n = 40; aged ∼ 22 wk) randomly received either OVX or sham (SHM) surgeries and then underwent the clamp 27 wk following surgeries. [3-(3)H]glucose was used to determine glucose clearance, whereas 2-[(14)C]deoxyglucose (2-DG) was used to assess glucose uptake in skeletal muscle, brown adipose tissue (BAT), subcutaneous white adipose tissue (WAT), and visceral WAT. OVX decreased the glucose infusion rate and glucose clearance in both lines, but HCR had better insulin sensitivity than LCR (P < 0.05). In both lines, OVX significantly reduced glucose uptake in soleus and gastrocnemius muscles; however, HCR showed ∼ 40% greater gastrocnemius glucose uptake compared with LCR (P < 0.05). HCR also exhibited greater glucose uptake in BAT and visceral WAT compared with LCR (P < 0.05), yet these tissues were not affected by OVX in either line. In conclusion, OVX impairs insulin sensitivity in both HCR and LCR rats, likely driven by impairments in insulin-mediated skeletal muscle glucose uptake. HCR rats have greater skeletal muscle, BAT, and WAT insulin-mediated glucose uptake, which may aid in protection against OVX-associated insulin resistance.
authors.affiliation: Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri;
authors.forename: Young-Min
authors.initials: YM
authors.lastname: Park
authors.affiliation: Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri; Medicine Division of Gastroenterology and Hepatology, University of Missouri, Columbia, Missouri; Research Service, Harry S. Truman Memorial Veterans Affairs Hospital, Columbia, Missouri;
authors.forename: R Scott
authors.initials: RS
authors.lastname: Rector
authors.affiliation: Department of Molecular Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas;
authors.forename: John P
authors.initials: JP
authors.lastname: Thyfault
authors.affiliation: Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri;
authors.forename: Terese M
authors.initials: TM
authors.lastname: Zidon
authors.affiliation: Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri; Department of Child Health, University of Missouri, Columbia, Missouri; Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri;
authors.forename: Jaume
authors.initials: J
authors.lastname: Padilla
authors.affiliation: Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri;
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Welly
authors.affiliation: Research Service, Harry S. Truman Memorial Veterans Affairs Hospital, Columbia, Missouri;
authors.forename: Grace M
authors.initials: GM
authors.lastname: Meers
authors.affiliation: Department of Molecular Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas;
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Morris
authors.affiliation: Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, Michigan; and.
authors.forename: Steven L
authors.initials: SL
authors.lastname: Britton
authors.affiliation: Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, Michigan; and.
authors.forename: Lauren G
authors.initials: LG
authors.lastname: Koch
authors.affiliation: Department of Biomedical Sciences, University of Missouri, Columbia, Missouri.
authors.forename: Frank W
authors.initials: FW
authors.lastname: Booth
authors.affiliation: Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri;
authors.forename: Jill A
authors.initials: JA
authors.lastname: Kanaley
authors.affiliation: Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri; vieirapotterv@missouri.edu.
authors.forename: Victoria J
authors.identifier: http://orcid.org/0000-0001-7563-0806
authors.initials: VJ
authors.lastname: Vieira-Potter
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D002001:Adipose Tissue, Brown / Q000378:metabolism; D000818:Animals; D002250:Carbon Radioisotopes; D003847:Deoxyglucose; D017079:Exercise Tolerance; D005260:Female; D005947:Glucose / Q000378:metabolism*; D015309:Glucose Clamp Technique; D007333:Insulin Resistance / Q000502:physiology*; D050152:Intra-Abdominal Fat / Q000378:metabolism; D008593:Menopause / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D010052:Ovariectomy; D051381:Rats; D050151:Subcutaneous Fat / Q000378:metabolism; D013997:Time Factors; D014316:Tritium
chemical_list: D002250:Carbon Radioisotopes; D014316:Tritium; D003847:Deoxyglucose; D005947:Glucose
keywords: aerobic fitness; brown adipose tissue; glucose uptake; insulin resistance; ovariectomy