Table 1.

Nucleotide turnover times and populations of nucleotides with the slow release rate in the absence and presence of blebbistatin

Sample	P2	T2 (s)	P2 + BLEBB	T2 + BLEBB (s)
Fast fibers	0.3 ± 0.03	250 ± 25 (20)	0.35 ± 0.05	3600 ± 500 (5)
Slow fibers	0.3 ± 0.04	150 ± 20 (15)	0.4 ± 0.05	>3600 (6)
Fast myosin	—	16 ± 4a	—	800 ± 100 (6)
Slow myosin	—	26b	—	820 ± 200 (5)

Values are expressed as the mean ± SE of 5–20 observations, as indicated by the numbers in parentheses after T2 values. T2, SRX nucleotide turnover time; P2, slow-release-rate nucleotide population.

^aATPase rate in the absence of blebbistatin taken from Myburgh et al. (40).

^bSteady-state ATPase rate of relaxed myofibrils taken from the data of Candau et al. (41).