Effect of hypoxia on cholesterol accumulation in cultured rabbit aortic smooth muscle cells.

We studied the effect of hypoxia on cholesterol accumulation in cultured rabbit aortic smooth muscle cells, which were incubated in a medium with normolipemic rabbit serum (NRS) or hyperlipemic rabbit serum (HRS). The cells were incubated in a humidified atmosphere of either 20% O2, 75% N2 and 5% CO2 (control cells) or 2% O2, 93% N2 and 5% CO2 (hypoxic cells). In a medium containing 20% NRS, the free cholesterol level of hypoxic cells was only a little higher than that of control cells, and there was no significant difference in esterified cholesterol content.

The effect of oxygen on the development of atherosclerosis in WHHL rabbits.

The effect of hyperoxic or hypoxic inhalation on blood lipid levels and on the development of atherosclerosis was studied in young male WHHL rabbits. They were exposed to ordinary room air containing different concentrations of oxygen: 6 animals were exposed to 40% oxygen (hyperoxia group) or 5-10% oxygen (hypoxia group) for 5 h a day, 5 days a week for 8 weeks. Four control rabbits inhaled ordinary room air.