Table 2.

Dobutamine Response in Wild-Type and Ames Dwarf Mice

	Wild Type (% change; N = 7)	Dwarf (% change; N = 8)
Heart rate	24 ± 4	23 ± 5
End-diastolic dimensions	−14 ± 3	−4 ± 1*
End-systolic dimensions	−40 ± 4	−15 ± 4*
Fractional shortening	57 ± 9	23 ± 9*
Diastolic wall thickness	26 ± 6	4 ± 4*
Systolic wall thickness	33 ± 5	10 ± 6*

Note: Physiological parameters of cardiac function were measured in eight wild-type and seven Ames dwarf mice at 10–11 mo of age. The percent change from the resting baseline state was calculated as (postinjection − preinjection/preinjection) × 100 and is shown as M ± SEM. *p < .05 vs wild type.