Effect of spinal cord transection on hyperlipemia induced by Tween 80

¹ Department of Neurological Surgery, The Neurological Institute, Columbia-Presbyterian Medical Center, New York City

Higher serum total lipid concentrations normally found in female rabbits indicate a sex-linked difference in homeostatic regulation of serum lipids. Following intravenous administration of Tween 80 an immediate increase in the serum total lipid concentration resulted from the addition of Tween and was similar in all experiments. A secondary increase in serum lipids of endogenous origin became maximum 6 hours after injection and differed in normal rabbits depending on sex. Transection of the spinal cord at the 5th thoracic level or above greatly reduced the secondary increase in both sexes, while transection at the 10th thoracic level or below did not change the response in females but reduced it in males. Complete adrenalectomy did not reduce the secondary increase in either sex. The findings indicate that the central nervous system, with peripheral connections between the 5th and 10th thoracic levels of the spinal cord, is important in the genesis of hyperlipemia induced by the surface-active agent, Tween 80. A function of testicular tissue dependent on innervation is also suggested.