SPECT Imaging Agents for Detecting Cerebral β-Amyloid Plaques

Table 2

Biodistribution of radioactivity after intravenous injection of [¹²⁵I]12, [¹²⁵I]13, [¹²⁵I]14, and [¹²⁵I] 15 in normal mice^a_.

Tissue	Time after injection (min)
	2	10	30	60
	[^125I]12
Blood	1.89 (0.28)	1.39 (0.10)	1.34 (0.07)	1.50 (0.09)
Liver	16.28 (0.90)	25.28 (0.31)	18.61 (1.81)	15.14 (0.89)
Kidney	8.13 (1.28)	5.21 (0.44)	3.85 (0.33)	3.05 (0.25)
Intestine	3.10 (0.61)	7.91 (1.05)	12.84 (1.18)	21.48 (3.17)
Spleen	2.57 (1.54)	2.31 (0.01)	1.76 (0.23)	1.52 (0.29)
Heart	4.87 (0.66)	2.66 (0.12)	1.67 (0.14)	1.28 (0.12)
Stomach^b	0.78 (0.02)	0.87 (0.22)	1.44 (0.69)	1.80 (0.84)
Brain	4.12 (0.15)	3.68 (0.18)	1.84 (0.12)	1.19 (0.04)
	[^125I]13
Blood	1.87 (0.18)	1.07 (0.08)	1.20 (0.15)	1.15 (0.16)
Liver	15.41 (0.98)	21.85 (2.14)	15.71 (0.96)	12.40 (2.38)
Kidney	8.33 (1.47)	4.31 (0.28)	3.40 (0.31)	2.32 (0.45)
Intestine	2.24 (0.24)	6.56 (0.83)	12.97 (1.15)	18.64 (2.05)
Spleen	2.72 (0.20)	1.92 (0.33)	1.58 (0.31)	1.18 (0.17)
Heart	5.63 (0.80)	2.47 (0.14)	1.69 (0.06)	1.07 (0.17)
Stomach^b	0.73 (0.17)	0.63 (0.16)	1.17 (0.40)	1.06 (0.27)
Brain	3.22 (0.15)	3.61 (0.60)	1.89 (0.21)	0.99 (0.10)
	[^125I]14
Blood	1.87 (0.21)	1.19 (0.17)	0.40 (0.01)	0.23 (0.09)
Liver	8.96 (1.48)	9.01 (0.97)	3.75 (0.47)	1.88 (0.61)
Kidney	7.99 (1.08)	6.30 (1.02)	4.51 (1.59)	1.46 (1.12)
Intestine	3.52 (0.29)	14.39 (0.80)	22.51 (1.11)	30.05 (3.61)
Spleen	2.70 (0.08)	1.38 (0.37)	0.55 (0.30)	3.67 (5.89)
Heart	4.98 (0.41)	2.25 (0.40)	0.84 (0.14)	0.47 (0.22)
Stomach^b	0.68 (0.06)	0.45 (0.18)	0.55 (0.33)	0.31 (0.07)
Brain	4.00 (0.18)	2.36 (0.33)	0.51 (0.07)	0.17 (0.05)
	[^125I]15
Blood	2.77 (0.43)	1.58 (0.18)	0.66 (0.03)	0.20 (0.02)
Liver	9.77 (1.89)	8.24 (0.50)	6.80 (0.86)	4.78 (1.09)
Kidney	14.79 (2.59)	15.11 (2.00)	6.45 (0.84)	1.66 (0.62)
Intestine	3.12 (0.37)	11.26 (0.63)	22.01 (1.34)	27.28 (0.48)
Spleen	3.92 (1.18)	1.55 (0.15)	0.56 (0.13)	0.17 (0.06)
Heart	5.51 (0.71)	1.60 (0.18)	0.53 (0.04)	0.12 (0.02)
Stomach^b	0.89 (0.09)	0.59 (0.16)	1.56 (0.50)	0.81 (0.36)
Brain	3.31 (0.32)	1.90 (0.07)	0.52 (0.03)	0.08 (0.02)

^aExpressed as % injected dose per gram. Each value represents the mean ± S.D. for 3−5 animals at each interval. ^bExpressed as % injected dose per organ.