Table 3.

Histomorphometric analysis of trabecular bone parameters in femur (mean ± SEM). N = 4-8 mice per group

	Wild type		Haploinsufficient		Null
Parameter	14 wk vehicle	14 wk PTH	14 wk vehicle	14 wk PTH	14 wk vehicle	14 wk PTH
Structure
Bone volume (BV/TV, %)	7.14 ± 0.49	11.70 ± 0.85 a	6.40 ± 0.51	9.85 ± 0.74	4.20 ± 0.46 b	5.99 ± 0.62 a
Trabecular thickness (μm)	29.14 ± 1.45	33.48 ± 1.70	26.63 ± 1.11	32.55 ± 1.78	26.82 ± 1.45	29.90 ± 2.01
Trabecular number (per mm)	2.43 ± 0.15	3.47 ± 0.17 a	2.40 ± 0.14	3.05 ± 0.22	1.52 ± 0.13 b	1.97 ± 0.13
Trabecular spacing (μm)	379 ± 27	259 ± 16	407 ± 24	313 ± 29	678 ± 73 b	503 ± 39 a
Formation
Osteoblast surface (ObS/BS, %)	19.87 ± 2.74	33.00 ± 2.23 a	18.14 ± 2.54	29.75 ± 1.57 a	15.87 ± 2.01	26.33 ± 1.97 a
Osteoblast number (NOb/BPm, /mm2)	12.71 ± 1.86	21.33 ± 1.68 a	11.45 ± 1.66	16.93 ± 0.62	10.51 ± 1.52	19.91 ± 1.71 a
Mineral apposition rate (MAR, μm/day)	0.41 ± 0.01	0.42 ± 0.03	0.44 ± 0.05	0.50 ± 0.04	0.41 ± 0.06	0.36 ± 0.05
Mineralizing surface (MS/BS, %)	11.11 ± 1.13	13.70 ± 1.17	12.33 ± 1.65	10.99 ± 2.14	10.38 ± 2.21	11.78 ± 0.95
Bone formation rate (BFR/BS, μm3/μm2/day)	0.038 ± 0.008	0.050 ± 0.009	0.063 ± 0.013	0.053 ± 0.011	0.031 ± 0.008	0.059 ± 0.014
Mineralization Lag Time (MLT, days)	3.95 ± 0.49	11.29 ± 1.64 a	5.17 ± 1.19	12.70 ± 3.49 a	3.62 ± 0.98	14.51 ± 1.29 a
Osteoid Volume (OV/BV, %)	2.01 ± 0.35	3.47 ± 0.21 a	2.52 ± 0.39	4.07 ± 0.52 a	1.85 ± 0.34	4.90 ± 0.61 a
Resorption
Eroded surface (%)	9.39 ± 0.87	11.20 ± 1.90 a	6.31 ± 1.04	11.99 ± 1.11 a	4.71 ± 0.86	9.72 ± 1.30 a
Osteoclast surface (OcS/BS, %)	1.79 ± 0.27	2.91 ± 0.36	1.85 ± 0.45	3.40 ± 0.48	1.54 ± 0.27	3.05 ± 0.40
Osteoclast number (NOc/BPm, /mm2)	0.83 ± 0.13	1.15 ± 0.12	0.79 ± 0.37	1.39 ± 0.78 a	0.69 ± 0.11	1.40 ± 0.19 a

^asignificantly different from corresponding vehicle treated, p ≤ 0.05

^bsignificantly different from vehicle treated wild type, p ≤ 0.05