Table 6. Biodistribution of ^99mTc-5 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	9.93 ± 2.37	11.38 ± 1.29	10.81 ± 5.48	4.17 ± 1.14	2.06 ± 0.85*b
brain	0.25 ± 0.04	0.01 ± 0.01	0.02 ± 0.01	0.01 ± 0.01	0.05 ± 0.01
blood	6.12 ± 2.22	1.02 ± 0.48	0.87 ± 0.43	0.14 ± 0.02	1.22 ± 0.01
heart	3.34 ± 0.47	0.62 ± 0.03	0.56 ± 0.31	0.11 ± 0.03	0.48 ± 0.25
lung	8.93 ± 0.54	2.31 ± 0.55	1.28 ± 0.27	0.74 ± 0.30	1.92 ± 0.41
liver	3.11 ± 0.82	1.67 ± 0.39	1.37 ± 0.45	0.50 ± 0.08	1.93 ± 0.77
skin	6.11 ± 1.06	1.14 ± 0.23	0.62 ± 0.10	0.16 ± 0.04	1.47 ± 0.68
spleen	2.56 ± 0.86	0.76 ± 0.21	0.55 ± 0.08	0.20 ± 0.13	0.33 ± 0.20
stomach	4.23 ± 0.38	1.14 ± 0.37	0.75 ± 0.06	0.25 ± 0.09	2.11 ± 0.84
kidneys	35.68 ± 2.10	37.23 ± 9.69	32.68 ± 6.55	8.39 ± 2.56	22.48 ± 9.23
muscle	1.37 ± 0.37	0.06 ± 0.06	0.15 ± 0.04	0.05 ± 0.01	0.39 ± 0.29
pancreas	1.43 ± 0.76	0.22 ± 0.08	0.01 ± 0.01	0.01 ± 0.01	0.25 ± 0.14
bone	2.09 ± 0.64	0.35 ± 0.29	0.03 ± 0.01	0.09 ± 0.07	0.19 ± 0.08
Percentage Injected Dose (% ID)
intestines	2.40 ± 0.36	2.84 ± 1.98	4.77 ± 3.46	0.59 ± 0.18	2.28 ± 0.78
urine	31.78 ± 3.81	73.27 ± 5.41	77.67 ± 5.88	93.77 ± 1.03	74.78 ± 10.44
Uptake Ratio of Tumor/Normal Tissue
tumor/blood	1.62	11.16	12.43	29.79	1.69
tumor/kidneys	0.28	0.31	0.33	0.50	0.09
tumor/lung	1.11	4.93	8.45	5.64	1.07
tumor/liver	3.19	6.81	7.89	8.34	1.07
tumor/muscle	7.25	189.67	72.07	83.40	5.28

^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-5 with or without NDP-MSH peptide blockade at 2 h postinjection.