Table 3. Biodistribution of ^99mTc-2 in B16/F1 Melanoma-Bearing C57 Mice^a.

tissue	0.5 h	2 h	4 h	24 h	2 h NDP
Percentage Injected Dose/Gram (% ID/g)
tumor	13.29 ± 2.36	13.85 ± 1.43	9.40 ± 2.86	5.23 ± 1.81	1.19 ± 0.30*b
brain	0.20 ± 0.01	0.02 ± 0.01	0.01 ± 0.01	0.01 ± 0.01	0.01 ± 0.01
blood	7.53 ± 0.99	1.48 ± 0.02	0.27 ± 0.17	0.06 ± 0.05	3.69 ± 0.01
heart	2.38 ± 1.75	0.27 ± 0.07	0.14 ± 0.05	0.09 ± 0.02	0.22 ± 0.01
lung	4.61 ± 3.16	0.53 ± 0.13	0.30 ± 0.01	0.16 ± 0.03	0.39 ± 0.14
liver	1.36 ± 0.10	0.78 ± 0.02	0.73 ± 0.07	0.43 ± 0.11	0.61 ± 0.08
skin	6.44 ± 2.64	1.33 ± 0.59	0.22 ± 0.15	0.22 ± 0.04	0.38 ± 0.08
spleen	1.19 ± 0.58	0.31 ± 0.15	0.27 ± 0.14	0.23 ± 0.06	0.21 ± 0.07
stomach	2.01 ± 0.72	0.83 ± 0.23	0.66 ± 0.20	0.37 ± 0.26	0.92 ± 0.37
kidneys	35.79 ± 2.11	28.60 ± 5.14	26.17 ± 4.83	11.50 ± 2.81	18.09 ± 1.89*b
muscle	0.46 ± 0.19	0.06 ± 0.05	0.02 ± 0.01	0.03 ± 0.03	0.04 ± 0.01
pancreas	1.25 ± 1.00	0.11 ± 0.09	0.02 ± 0.02	0.05 ± 0.03	0.07 ± 0.03
bone	0.90 ± 0.90	0.29 ± 0.20	0.09 ± 0.07	0.11 ± 0.06	0.11 ± 0.04
Percentage Injected Dose (% ID)
intestines	2.28 ± 1.24	0.93 ± 0.21	1.29 ± 0.47	2.03 ± 1.42	0.84 ± 0.22
urine	53.46 ± 7.42	77.83 ± 2.83	84.94 ± 2.10	90.45 ± 3.66	90.63 ± 2.07
Uptake Ratio of Tumor/Normal Tissue
tumor/blood	1.76	9.36	34.81	87.17	0.32
tumor/kidneys	0.37	0.48	0.36	0.45	0.07
tumor/lung	2.88	26.13	31.33	32.69	3.05
tumor/liver	9.77	17.76	12.88	12.16	1.95
tumor/muscle	28.89	230.83	470.00	174.33	29.75

^aThe data are presented as percent injected dose/gram or as percent injected dose (mean ± SD, n = 4).

^b(∗) p < 0.05 for determining the significance of differences in tumor and kidney uptake between ^99mTc-2 with or without NDP-MSH peptide blockade at 2 h postinjection.