Pediatric Cardiology

, Volume 32, Issue 5, pp 659–666 | Cite as

Cellular and RAS Changes in the Hearts of Young Obese Rats

  • Kee Soo Ha
  • Kee Hwan Yoo
  • Hyung Eun Yim
  • Gi Young Jang
  • In Sun Bae
  • Young Sook Hong
  • Joo Won Lee
Original Article

Abstract

Obesity during childhood increases the risk of cardiac disease, hypertension, and other complications in adulthood. We investigated the cellular and renin-angiotensin system changes of the heart in obese young rats. We used Sprague–Dawley rats and early obesity was induced by overfeeding through adjusting the number of male pups per dam during the first 28 days of life. The body weight, heart weight, blood pressure, serum glucose, and blood pressure were assessed and we performed echocardiography, proliferating cell nuclear antigen (PCNA); assessment, apoptosis and Masson’s trichrome staining, and Western blotting and the results were compared between the normal litter (NL, control) and the small litter (SL, obesity). There were no differences in blood pressure and serum glucose, but the body weight increased 61.2% and the interventricular septal thickness in diastole on the echocardiography was increased in the SL. There was hyperplasia of the PCNA cells and apoptotic cells without cellular hypertrophy or change of the amount of collagen in the SL. On Western blotting, rennin, and angiotensin II type 2 receptor (AT2R) were increased without a change of angiotensin II type 1 receptor (AT1R) in the SL. Early obesity caused echocardiographically detected septal hypertrophy and an increase of cellular turnover. Renin and AT2R were upregulated without a change of AT1R and the increase of AT2R was regarded as a cardioprotective effect against the pathologic conditions caused by the early obesity.

Keywords

Apoptosis PCNA Hypertrophy Obesity Renin angiotensin system 

Notes

Acknowledgment

This work was supported by the Korea Research Foundation (K. H. Yoo) funded by the Korean Government (grant No. KRF-2008-313-E00308).

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Kee Soo Ha
    • 1
  • Kee Hwan Yoo
    • 1
  • Hyung Eun Yim
    • 1
  • Gi Young Jang
    • 1
  • In Sun Bae
    • 1
  • Young Sook Hong
    • 1
  • Joo Won Lee
    • 1
    • 2
  1. 1.Department of Pediatrics, College of MedicineKorea UniversitySeoulSouth Korea
  2. 2.Department of Pediatrics, Guro HospitalKorea University Medical CenterSeoulSouth Korea

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