Table 3.

Histological examination of sternal marrow sections from female BALB/c mice dosed with BU at 10.50 mg/kg on 8 occasions over 23 days, and sampled at 1, 19, 49, 91 and 112 days after the final BU dose^a

	Cellularity		Myelopolesis		Erythropoiesis		Megakaryopoiesis		Fat
Day	Control	BU	Control	BU	Control	BU	Control	BU	Control	BU
1	3.0	0.6	3.0	0.2	3.0	0.0	3.0	0.0	0.0	4.8
19	3.0	1.2	3.0	1.2	3.0	0.0	3.0	0.4	0.2	4.6
49	3.0	2.4	3.0	2.6	3.0	0.2	3.0	1.2	0.2	1.8
91	3.0	2.0	3.0	2.2	3.0	1.6	3.0	1.4	0.2	2.2
112	3.0	2.8	3.0	3.0	3.0	1.8	3.0	1.6	0.4	2.4

^aValues are means; n = 5 for control and BU-treated mice at each point. Sections were assessed for cellularity, myelopoiesis, erythropoiesis, megakaryopoiesis and the presence of fat and graded on a 6 point scale: 0 = absent; 1 = very slight; 2 = slight; 3 = moderate; 4 = marked; 5 = very marked. Results were not analysed stastically.