Table 5

Inhibitor effects (I₅₀values) on AMPD from skeletal muscle of control versus frozen wood frogs
	Control		Frozen

	Free AMPD	Bound AMPD	Free AMPD	Bound AMPD

Mg·GTP, mM	0.15 ± 0.02	0.08 ± 0.01	0.08 ± 0.01 ^a	0.10 ± 0.01
IMP, mM	NE	NE	NE	0.23 ± 0.02 ^a
KCl, mM	660 ± 44	148 ± 34	702 ± 21 ^a	162 ± 24
NaCl, mM	973 ± 20	141 ± 31	824 ± 26 ^a	133 ± 21
NH₄Cl, mM	276 ± 5.0	ND	254 ± 10	ND

Data are means ± SEM, for determinations on Sephadex G50-filtered muscle extracts from n = 4 individual frogs. I₅₀is the inhibitor concentration that reduces enzyme velocity by 50%. ^a– Significantly different from the corresponding value for muscle from control frogs as assessed by the Student's t-test, P < 0.05. NE, no effect. ND, not determined. I₅₀values were measured at an AMP concentration of 0.5 mM.
Dieni and Storey BMC Biochemistry 2008 9:12 doi:10.1186/1471-2091-9-12