Abstract
Coronary capillary geometry was studied in male rats treated with 3,3',5-triiodo-L-thyronine (T3; Hyper), 6-N-propyl-2-thiouracil (PTU; Hypo), or a sequence of PTU and T3 (Hypo/Hyper). Ventricular mass and heart-to-body mass ratios revealed myocardial hypertrophy in Hyper, atrophy in Hypo, and a return of ventricular mass to control (Con) values in Hypo/Hyper rats. From cross-sectional analysis, capillary densities for Hyper and Hypo/Hyper were comparable with Con, despite increased left ventricular mass. Hypo rats demonstrated increased capillary density. In Hyper and Hypo rats, tissue area surrounding individual capillaries (capillary domain) decreased, compared with Con, for capillaries close to the feeding arteriole. In Hyper and Hypo/Hyper, capillaries distal to the feeding arteriole had similar domain areas as Con; in Hypo, this area was smaller. From longitudinal analysis, capillary segment lengths were significantly shorter in all groups compared with Con. Our data suggest that while hypothyroidism induced myocardial atrophy and hyperthyroidism induced myocardial hypertrophy, both thyroid states stimulated capillary proliferation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
