title: Complete reversibility of physiological coronary vascular abnormalities in hypertrophied hearts produced by pressure overload in the rat.
abstract: Using an experimental model of ascending aortic banding in the rat, we examined whether coronary circulation abnormalities in hypertrophied hearts are reversible after debanding. 4-wk banding produced significant increases in in vivo left ventricular (LV) pressure (194 +/- 13 vs. 114 +/- 9 mmHg in shamoperated controls) and LV dry wt/body wt (48 +/- 5% above controls). In isolated hearts perfused with Krebs-Henseleit buffer, coronary flow rate (CFR) was estimated under nonworking conditions. During maximal vasodilation after 1 min-ischemia, CFR at a coronary perfusion pressure (CPP) of 100 mmHg and CFR/myocardidial mass at CPPs of 100 and 150 mmHg decreased significantly (72 +/- 5%; 53 +/- 4 and 61 +/- 4% of controls). 1 or 4 wk after debanding, LV systolic pressures were similar to control values, and the degree of myocardial hypertrophy decreased to levels 23 +/- 6 (P less than 0.01) and 11 +/- 6% (P less than 0.01) above their control values, respectively. At 1 wk there was no significant increase in CFR/myocardial mass, compared to values in the banded group (67 +/- 8 vs. 53 +/- 4% of controls at 100 mmHg and 67 +/- 9 vs. 61 +/- 4% at 150 mmHg of CPP). At 4 wk, CFR and the ratio had increased toward normal. Thus, decreased coronary perfusion in hypertrophied hearts is completely reversible.
authors.affiliation: First Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Isoyama
authors.forename: N
authors.initials: N
authors.lastname: Ito
authors.forename: M
authors.initials: M
authors.lastname: Kuroha
authors.forename: T
authors.initials: T
authors.lastname: Takishima
mesh_terms: D000818:Animals; D001011:Aorta / Q000503:physiopathology; D001794:Blood Pressure; D001835:Body Weight; D006332:Cardiomegaly / Q000503:physiopathology*; D003326:Coronary Circulation; D006439:Hemodynamics; D008297:Male; D009929:Organ Size; D051381:Rats; D011919:Rats, Inbred Strains