TABLE 1.

In vitro motility data using HMM and showing the effect of myosin isoform composition and temperature on the amrinone-induced reduction in sliding velocity

HMM preparation	% reduction of sliding velocity at two temperaturesa
	28.6 °C	22.9 °C
	%	%
Fast leg muscleb	28.9	31.3
Musculus psoas majorc, prepared April, 2007	20.7	13.3
M. psoas majorc, prepared October, 07	17.3	11.5

^a Each numerical value was based on more than 147 filament paths in both test and control.

^b Similar amounts of MHC IIx and MHC IIb according to Ref. 24 and confirmed in the present work (data not shown).

^c This muscle contains almost exclusively MHC IIx (43).