|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Kinesiology, Temple University, Philadelphia, Pennsylvania, United States
2 Physiology, Temple University, Philadelphia, Pennsylvania, United States
3 Cardiovascualr Research Center, Temple University, Philadelphia, Pennsylvania, United States
4 Physiology, Cardiovascular Research Center, Temple University, Philadelphia, Pennsylvania, United States
5 Kinesiology, Physiology, Cardiovascular Research Center, Temple University, Philadelphia, Pennsylvania, United States
* To whom correspondence should be addressed. E-mail: jlibonat{at}temple.edu.
Hypertension and exercise independently induce left ventricular (LV) remodeling and alter LV function. The purpose of this study was to determine systolic and diastolic LV pressure-volume relationships (LV-PV) in spontaneously hypertensive rats (SHR) with and without LV hypertrophy, and to determine whether 6 months of exercise training modified the LV-PV in SHR. 4-Month old female SHR (n=20), were assigned to a sedentary (SHR-SED) or treadmill-trained (SHR-TRD) group (approximately 60% VO2 peak, 5 d/wk, 6 months), while age-matched female Wistar-Kyoto rats (WKY;n=13), served as normotensive controls. The LV-PV was determined using a Langendorff isolated heart preparation at 4 (no hypertrophy; WKY,n=5; SHR,n=5) and 10 months of age (hypertrophy; WKY,n=8; SHR-SED,n=8; SHR-TRD,n=7). At 4 months, the LV-PV in SHR was similar to that observed in WKY controls. However, at 10 months of age, a rightward shift in the LV-PV occurred in SHR. Exercise training did not alter the extent of the shift in the LV-PV relative to SHR-SED animals. Relative systolic function (P<0.05), i.e. relative systolic elastance, was approximately 50% lower in SHR than WKY at 10 months of age. Doppler-derived LV filling parameters [early wave (E), atrial wave (A), and the E/A ratio] were similar between groups. LV capacitance was increased in SHR at 10 months (P<0.05) while LV diastolic chamber stiffness was similar between groups at 10 months. Hypertrophic remodeling at 10 months of age in female SHR is manifest with relative systolic decompensation and normal LV diastolic function. Exercise training did not alter the LV-PV in SHR.
This article has been cited by other articles:
![]() |
H. Hwang, R. A. Kloner, M. T. Kleinman, and B. Z. Simkhovich Direct and Acute Cardiotoxic Effects of Ultrafine Air Pollutants in Spontaneously Hypertensive Rats and Wistar--Kyoto Rats Journal of Cardiovascular Pharmacology and Therapeutics, September 1, 2008; 13(3): 189 - 198. [Abstract] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |