A managed care company says it has borrowed $750 million by selling senior notes to public investors.

Humana Inc., Louisville, Ky., says it raised $500 million by issuing notes that pay an interest rate of 7.2% and are due in June 2018.

The company raised $250 million by selling notes that pay 8.15% and are due in June 2038.

Humana will use the senior notes proceeds to pay off about $750 million borrowed through an unsecured revolving credit agreement, the company says.

The company is using swaps to try to make net interest expense charges correspond with changes in net investment income, to reduce the effect of rate changes on earnings, Humana says.