Table 2.

Aβ Level in APP and APP/CCL2 Transgenic Mouse Brain

Genotype	Age (months)	n	Aβ	2% SDS Aβ ng/mg protein*	5 mol/L guanidine Aβ ng/mg protein†	Total Aβ ng/mg protein‡	Total Aβ40 + Αβ42 ng/mg protein3
APP	14	6	Aβ40	38.3 ± 8.4	130.7 ± 17.0	54.1 ± 8.6	61.0 ± 9.0
			Aβ42	7.1 ± 2.2	8.1 ± 0.8	6.9 ± 0.6
			Aβ42/Aβ40	21.2 ± 3.7	6.8 ± 1.2	14.0 ± 2.0
APP/CCL2	14	6	Aβ40	70.5 ± 13.1§	298.5 ± 54.6§	102.5 ± 15.4§	117.3.±17.1§
			Aβ42	13.7 ± 2.1¶	22.6 ± 2.8||	14.8 ± 2.1¶
			Aβ42/Aβ40	18.7 ± 1.7	8.3 ± 1.0	14.5 ± 1.3

Brain cerebrum has been homogenized in 2% SDS buffer and ultracentrifuged as described in the Material and Methods. SDS-soluble Aβ40 and Aβ42 levels in the supernatant fraction were presented as 2% SDS values. The SDS-insoluble fraction was solubilized in 5 mol/L guanidine buffer and its Aβ40 and Aβ42 values were presented as 5 mol/L guanidine values. 

^*Total protein in SDS soluble fraction. 

^†Total protein in SDS insoluble fraction. 

^‡Total protein in SDS soluble and insoluble fraction. 

^§, ^¶, and ^|| in APP/CCL2 group denotes P < 0.05, 0.01, and 0.001 versus corresponding Aβ value of APP group as determined by Student’s t-test, respectively.