Table 2.

Mechanical properties of the femur measured by the three‐point bending test. Bone mechanical properties were measured in femurs dissected at the end of the 28‐day dosing for the four treatment groups (n = 7‐8 mice/group): Vehicle (control), iPTH, iPTH + L‐NAME and L‐NAME alone

Group	Control	iPTH	iPTH + L‐NAME	L‐NAME
Diameter femurs (mm)	1.16 ± 0.06	1.22 ± 0.04	1.18 ± 0.03	1.19 ± 0.05
Yield load (N)	12.0 ± 1.3b	14.1 ± 1.0a	14.6 ± 1.5a, c	12.5 ± 1.3b
Ultimate load (N)	13.5 ± 1.0b	15.5 ± 0.7a	16.6 ± 1.1a, c	14.9 ± 1.7b
Breaking load (N)	10 ± 2	12 ± 2	11 ± 2	10 ± 4
Yield extension (mm)	0.18 ± 0.02	0.19 ± 0.03	0.18 ± 0.01	0.17 ± 0.03
Ultimate extension (mm)	0.26 ± 0.05	0.25 ± 0.03	0.24 ± 0.03	0.24 ± 0.05
Breaking extension (mm)	0.5 ± 0.1	0.4 ± 0.2	0.5 ± 0.1	0.4 ± 0.1
Stiffness (N/mm)	70 ± 6	80 ± 7	87 ± 10a	79 ± 11
Elastic modulus (MPa)	4763 ± 945	4530 ± 654b	5580 ± 516	5037 ± 363
Yield stress (MPa)	69 ± 9b	72 ± 6	83 ± 10a, c	71 ± 8b
Ultimate stress (MPa)	78 ± 10b	79 ± 5b	93 ± 6a	84 ± 8
Breaking stress (MPa)	58 ± 9	61 ± 13	60 ± 7	57 ± 22
Yield strain	0.015 ± 0.002	0.017 ± 0.003	0.016 ± 0.001	0.015 ± 0.002
Ultimate strain	0.022 ± 0.005	0.023 ± 0.002	0.021 ± 0.003	0.021 ± 0.003
Breaking strain	0.04 ± 0.01	0.04 ± 0.02	0.04 ± 0.01	0.04 ± 0.01
Work to fracture (mJ)	4.3 ± 1.3	4.3 ± 2.2	5.1 ± 0.7	4.0 ± 1.7
Work yield to fracture (mJ)	3.3 ± 1.3	3.0 ± 2.2	3.8 ± 0.7	3.0 ± 1.7

Values are mean ± SD;

^a P < 0.05 versus control;

^b P < 0.05 versus iPTH + L‐NAME;

^c P < 0.05 versus L‐NAME.