title: Age-related changes and inheritance of lactate transport activity in red blood cells.
abstract: In red blood cell membranes, the activity of the main lactate carrier, H+-monocarboxylate co-transporter (MCT), varies interindividually and its distribution is bimodal. To show the repeatability of MCT activity, 2 to 5 blood samples were taken, at an interval of approximately 1 year, from 51 Standardbred horses, age 2 weeks-8 years, for a total of 128 observations. The horses could be divided into low (LT) and high (HT) lactate transport activity groups. Age significantly affected (P<0.05) MCT activity such that activity was highest in foals, reached a nadir at 2-3 years, and tended to increase again thereafter. Interindividual variation was not sufficiently high to allow a horse to switch from the LT-group to the HT-group, or vice versa. When MCT activity from 4 sires, 15 dams and their 52 offspring was analysed, the data showed that MCT activity is heritable and supported the hypothesis that low MCT activity was caused by a recessive allele in a single autosomal locus. Because MCT activity affects RBC lactate concentrations, the phenomenon may be physiologically significant.
authors.affiliation: Department of Basic Veterinary Sciences, University of Helsinki, Finland.
authors.forename: L K
authors.initials: LK
authors.lastname: Väihkönen
authors.forename: M
authors.initials: M
authors.lastname: Ojala
authors.forename: A R
authors.initials: AR
authors.lastname: Pösö
mesh_terms: D000375:Aging / Q000097:blood*; D000818:Animals; D001692:Biological Transport; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D006736:Horses / Q000097:blood* / Q000235:genetics; D007773:Lactates / Q000097:blood*; D008297:Male; D027501:Monocarboxylic Acid Transporters / Q000097:blood / Q000235:genetics; D015203:Reproducibility of Results
chemical_list: D007773:Lactates; D027501:Monocarboxylic Acid Transporters