F. Franco et al., MAGNETIC-RESONANCE-IMAGING ACCURATELY ESTIMATES LV MASS IN A TRANSGENIC MOUSE MODEL OF CARDIAC-HYPERTROPHY, American journal of physiology. Heart and circulatory physiology, 43(2), 1998, pp. 679-683
Transgenic mice with a dysfunctional guanylyl cyclase A gene (GCA -/-)
are unable to transduce the signals from atrial naturetic peptide and
develop hypertension and cardiac hypertrophy Magnetic resonance imagi
ng (MRI) was performed to assess cardiac hypertrophy in these animals,
using wild-type siblings as controls. Anesthetized mice were studied
by gated multislice, multiphase cine MRI at 1.5 T. Simpson's rule was
used to estimate left ventricle (LV) mass and volumes from short-axis
images. Correlation between LV mass evaluated by MRI and at necropsy w
as excellent, with LVnecropsy = 1.04 x LVMRI + 4.69 mg (r(2) = 0.95).
By MRI, GCA -/- LV mass was significantly different when compared with
isogenic controls [GCA -/-, 226 +/- 43 mg (n = 14) vs. controls, 156
+/- 14 mg (n = 10); P < 0.0001]. LV volumes and ejection fraction in t
he two groups were not significantly different. MRI provides an accura
te means for the noninvasive assessment of murine cardiac phenotype an
d may be useful in following the effects of genetic modification.