Association between P2X7 Receptor Polymorphisms and Bone Status in Mice

Table 2

Bone parameters and concentration of in vivo bone markers presented as means (±SD). Number of animals in each strain is indicated at the top of the table (𝑛). BMD, BMC, and bone area, in whole body or femoral region was determined by DXA scanning. An electronic digital caliper measured femoral length, before bone strength of the femur was determined by a 3-point bending test. In vivo bone markers were measured on serum using commercial available kits. One-way ANOVA was performed to test differences between groups and post hoc Bonferroni corrections, using 0.05 as the significance level. Simple descriptive of data is presented as means and standard deviations (SD). Significant difference between the 129X1/SvJ, BALB/cJ, B6, and DBA/2 animals at the 𝑃<0.05 level is extracted from Bonferroni multiple comparison analysis and indicated with asterisks when different from the three other strains, with A when different from 129X1/SvJ, with B when different from B6, with C when different from BALB/cJ, and with D when different from DBA/2J.

Sample size (𝑛)	129X1/SvJ	BALB/cJ	B6	DBA/2J	SWR/J	C57L/J	AKR/J	SJL/J	NZB/BlNJ	C3H/HeJ	ANOVA one way
	15	14	16	14	14	15	15	15	15	15
P451L genotype	P	P	L	L	L	L	L	L	L	L
Bone Parameters
BMD (g/cm^2)	0.0562^*	0.0513^A, D	0.0502^A, D	0.0468^*	0.0477	0.0579	0.0576	0.0548	0.0525	0.0563	<0.001
	(±0.0020)	(±0.0018)	(±0.0020)	(±0.0022)	(±0.0013)	(±0.0030)	(±0.0021)	(±0.0015)	(±0.0041)	(±0.0018)
BMC (g)	0.535^*	0.471^A, D	0.458^A, D	0.358^*	0.394	0.548	0.593	0.459	0.465	0.558	<0.001
	(±0.045)	(±0.028)	(±0.031)	(±0.029)	(±0.035)	(±0.042)	(±0.046)	(±0.025)	(±0.064)	(±0.036)
Area (cm^2)	9.53^D	9.19^D	9.13^D	7.65^*	8.26	9.46	10.29	8.38	8.83	9.90	<0.001
	(±0.53)	(±0.30)	(±0.40)	(±0.41)	(±0.54)	(±0.35)	(±0.60)	(±0.40)	(±0.60)	(±0.50)
BMD in femur region (g/cm^2)	0.0798^B, D	0.0764^B, D	0.0655^A, C	0.0639^A, C	0.0650	0.0786	0.0782	0.0774	0.0740	0.0826	<0.001
	(±0.0039)	(±0.0021)	(±0.0033)	(±0.0028)	(±0.0024)	(±0.0049)	(±0.0036)	(±0.0032)	(±0.0052)	(±0.0037)
BMC in femur region (g)	0.0439^B,D	0.0402^D	0.0364^A, D	0.0281^*	0.0307	0.0464	0.0466	0.0391	0.0378	0.0439	<0.001
	(±0.0044)	(±0.0028)	(±0.0026)	(±0.0026)	(±0.0021)	(±0.0044)	(±0.0029)	(±0.0030)	(±0.0060)	(±0.0036)
Area of femur region (cm^2)	0.552^D	0.529^D	0.558^D	0.443^*	0.476	0.595	0.599	0.507	0.511	0.533	<0.001
	(±0.035)	(±0.031)	(±0.027)	(±0.035)	(±0.031)	(±0.046)	(±0.026)	(±0.032)	(±0.053)	(±0.028)
Femur length (mm)	15.25^D	15.06^D	15.53^D	14.34^*	14.29	15.79	16.00	14.08	15.90	15.61	<0.001
	(±0.36)	(±0.64)	(±0.23)	(±0.45)	(±0.40)	(±0.33)	(±0.69)	(±0.28)	(±0.45)	(±0.64)
Strength/Max. load femurs (𝑁)	31.5^*	24.6^*	16.3^A, C	18.7^A, C	16.7	28.0	30.5	20.0	23.3	33.9	<0.001
	(±3.2)	(±1.7)	(±1.1)	(±1.5)	(±0.8)	(±2.4)	(±2.8)	(±0.8)	(±3.0)	(±2.3)
In vivo bone markers
Osteocalcin (ng/mL)	40.0^C, D	55.91^*	38.42^C, D	71.72^*	38.44	36.49	72.37	51.09	48.49	63.22	<0.001
	(±9.48)	(±11.78)	(±11.11)	(±10.89)	(±8.97)	(±8.75)	(±11.25)	(±10.20)	(±8.06)	(±11.38)
ALP (nmol/mL)	266.8	314.2	260.2	317.6	272.5	179.7	190.9	213.7	299.4	270.6	<0.001
	(±56.1)	(±41.2)	(±63.8)	(±60.5)	(±39.9)	(±48.3)	(±62.5)	(±59.6)	(±36.3)	(±56.3)
RatLaps-Telopeptide collagen (ng/mL)	14.28^B,C	19.09^*	9.81^A, C	12.13^C	10.75	9.37	7.07	7.15	8.83	8.76	<0.001
	(±3.45)	(±4.40)	(±1.86)	(±1.88)	(±1.62)	(±2.53)	(±2.62)	(±1.83)	(±1.95)	(±4.02)