TABLE 2

Calculations for tissue cholesterol biosynthesis and uptake rates

Line #	Parameter	Serum		Retina		Brain
Line #	Parameter	VEH	SIM	VEH	SIM	VEH	SIM
Cholesterol content
1	Serum, mg/dl; retina and brain, nmol/mg protein	163	132	64.4	48.8	271	265
2	µg/g wet tissue			2576	1952	12,163	11,893
Treatment with dietary D7-cholesterol
3	D₇-cholesterol appearance, 2 wk, %	37	47	1.5	1.8	0.2	0.2
4	Tissue cholesterol uptake, 2 wk, %			3.8	3.8	0.5	0.5
Treatment with deuterated water
5	Total ²H cholesterol enrichment, 2 wk, %	16	12	16	9	13	12
6	²H cholesterol enrichment from tissue uptake, 2 wk, %			0.7	0.5	0.09	0.06
7	Tissue cholesterol biosynthesis, 2 wk, %			15.3	8.5	12.9	11.9
Summary data
8	Absolute rate of cholesterol input, μg/day/g wet tissue (%)			35.7 (100)	17.2 (100)	116.9 (100)	106.0 (100)
9	Local biosynthesis, μg/day/g wet tissue (%)			28.2 (79)	11.9 (69)	112.2 (96)	101.4 (96)
10	Uptake from blood, μg/day/g wet tissue, (%)			7.5 (21)	5.3 (31)	4.7 (4)	4.6 (4)
11	Tissue cholesterol turnover, days			72	113	104	112