Biogerontology

, Volume 6, Issue 1, pp 49–60

Effects of ovariectomy and growth hormone administration on body composition and vascular function and structure in old female rats

  • C. Castillo
  • M. Cruzado C. Ariznavarreta
  • V. Lahera
  • V. Cachofeiro
  • P. Gil-Loyzaga
  • Jesús A. F. Tresguerres
Research article

DOI: 10.1007/s10522-004-7383-x

Cite this article as:
Castillo, C., Ariznavarreta, M.C.C., Lahera, V. et al. Biogerontology (2005) 6: 49. doi:10.1007/s10522-004-7383-x

Abstract

Aging and estrogen-deprivation induce deleterious effects on body composition and vascular function in females. On the other hand, growth hormone (GH), whose production is reduced by age, exerts several vascular effects. The aim of this study was to investigate the effect of long-term estrogen deprivation and GH administration on body composition, vascular function and structure in aged female rats. Methods: Twelve female Wistar rats were ovariectomized at 10 months of age. At 20 months of age, half of the ovariectomized rats were treated with GH for 4 weeks. The remaining ovariectomized rats animals and one group of six intact females were used as control groups. After the treatment period, animals were sacrificed and Specific Gravity Index (SGI) and periuterine fat weigh, as well as vascular reactivity and morphometry in aortic rings, were studied. Results: No significant differences were found in SGI and periuterine fat weigh between ovariectomized and intact control rats. SGI was significantly increased by GH, and periuterine fat was reduced by the treatment. Dose-dependent relaxing responses to acetylcholine and isoproterenol were significantly diminished in ovariectomized rats as compared with intact animals, and GH treatment improved these responses. Ovariectomized animals showed significantly higher contracting responses to phenylephrine, acetylcholine + L-NAME and angiotensin-I than intact rats, and treatment with GH reduced them significantly. Media cross-sectional area was increased in ovariectomized rats as compared to intact animals, and GH reduced this area, but differences did not reach significance. Conclusion: GH has beneficial effects in body composition and endothelial function in old ovariectomized female rats.

Keywords

agingendothelial functionestrogensgrowth hormoneovariectomyvascular structure

Abbreviations

Ach

acetylcholine

A-I

angiotensin I

A-II

angiotensin-II

EDHF

endothelial-derived hyperpolarizing factor

GHD

growth hormone deficiency

IGF-1

insulin-like growth factor

Iso

isoproterenol

L-NAME

NG-nitro-L-arginine methylester

NO

nitric oxide

PE

phenylephrine

PGI2

prostacyclin

KCl

potassium chloride

rhGH

recombinant human growth hormone

SGI

specific gravity index

SNP

sodium nitroprusside

TXA2

tromboxane A2

Copyright information

© Springer 2005

Authors and Affiliations

  • C. Castillo
    • 1
  • M. Cruzado C. Ariznavarreta
    • 1
  • V. Lahera
    • 1
  • V. Cachofeiro
    • 1
  • P. Gil-Loyzaga
    • 2
  • Jesús A. F. Tresguerres
    • 1
  1. 1.Department of Physiology, School of MedicineComplutense UniversityMadridSpain
  2. 2.Department of Surgery II (Neurobiology of Hearing), School of MedicineComplutense UniversityMadridSpain