Table 2

[³H]FU and [³H]FUdR levels in inferior vena cava (IVC) and in hepatic veins (HV) of rats intravenously injected with the free or L-HSA-conjugated drugs

Drug	Means of Administration	Dose	Time	Levels		Levels in HV/Levels in IVC
Drug	Means of Administration	Dose	Time	IVC	HV	Levels in HV/Levels in IVC
		μg/g	h	ng/ml
Free FUdR	Bolus	0.5	0.5	BML^2-a	BML
		2.5	0.25	360.2 ± 24.3	54.1 ± 5.5^***	0.2
	1-h Infusion	0.5		53.1 ± 4.4	BML	<0.4
Conjugated FUdR	Bolus	0.5	0.5	45.6 ± 2.9	54.8 ± 4.2	1.2
			1	28.0 ± 1.1	47.5 ± 5.2	1.7
	1-h Infusion	0.25		BML	BML
		0.5		26.3 ± 1.3	37.8 ± 2.6	1.4
		1		28.4 ± 0.5	30.3 ± 1.5	1.1
Free FU	Bolus	0.5	0.25	50.6 ± 8.5	BML	<0.4
			0.5	BML	BML
		15^2-b	0.25	4344.0 ± 130.0	748.6 ± 55.2^***	0.2
			0.5	347.4 ± 30.0	55.8 ± 8.3^***	0.2

Data were obtained from three rats and are given as mean ± S.E. When the difference between the drug level in IVC and HV is statistically significant (Student's t test), it is indicated by asterisks (^***p < 0.001).

↵2-a Below measurable level (<20 ng/ml).
↵2-b Commonly used dose in human chemotherapy with FU (Heriot and Kumar, 1998).