Spinal cord energy metabolism in normal and postlaminectomy cats

Abstract

This study determined normal concentrations of ATP, ADP, AMP, phosphocreatine (P-creatine), glucose, lactate and pyruvate in upper (L-2) and lower (L-5) feline lumbar spinal cord, and whether previously reported laminectomy-induced reduction in spinal cord blood flow (SCBF) resulted in disturbance of spinal cord energy metabolism. Concentrations of ATP, P-creatine, pyruvate and glucose were significantly higher at L-5 than at L-2, probably as the result of larger amounts of gray matter at L-5 than L-2. Significant increases in ADP and AMP levels were the only metabolite changes noted 15 min following laminectomy. The increase in ADP and AMP may be due to a laminectomy-induced stimulation of ATP utilization. Lack of change in other metabolites implies an efficient energy homeostasis. Although laminectomy can reduce SCBF, the degree of this reduction is apparently insufficient to adversely affect spinal cord energy metabolism. Tissue from beneath or near the laminectomy site is viable and essentially normal.