Growth hormone replacement attenuates diastolic dysfunction and cardiac angiotensin II expression in senescent rats

Academic Article

Abstract

  • We tested the hypothesis that long-term growth hormone (GH) replacement in aged rats would preserve diastolic function and attenuate left ventricular remodeling associated with normal aging. Male Brown Norway × F344 rats were randomized to receive twice daily injections of porcine GH (200 μg/injection, subcutaneous) or saline from 24 to 30 months of age. Adult rats (6- to 9-months old) received saline injections throughout the study. Thirty-month-old, saline-treated rats exhibited low levels of insulin-like growth factor 1 (IGF-1), impaired diastolic left ventricular filling (Doppler), increased cardiac angiotensin II (Ang II), reduced plasma Ang II, and increased cardiac collagen. GH administration in old rats restored IGF-1 and diastolic indices to values comparable to those of adults. These effects were associated with reduced cardiac Ang II and attenuations in cardiac collagen. Age-related decreases in GH and IGF-1 may contribute to the decline in diastolic function of aging, in part through alterations in renin-angiotensin system-mediated ventricular remodeling. Copyright 2006 by The Gerontological Society of America.
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    Digital Object Identifier (doi)

    Author List

  • Groban L; Pailes NA; Bennett CDL; Carter CS; Chappell MC; Kitzman DW; Sonntag WE
  • Start Page

  • 28
  • End Page

  • 35
  • Volume

  • 61
  • Issue

  • 1