Metabolic changes following transection of the spinal cord in dogs.

Abstract

The influence of the central nervous system on metabolism and endocrine activity as based on functional alterations following transection of the brain stem in dogs has been previously reported by Anderson and her associates (1955), The present paper continues the theme, dealing with animals which have been subjected to transection of the spinal cord. Data available oll metabolic changes in patients and experimental animals with spinal cord lesions are rather meager. Grafe (I928), a pioneer in this field, reported increased nitrogen excretion following cervical cord transection in dogs. He suggested that the nitrogen loss was due to the interruption of the temperature-regulating pathways from the higher centers to the periphery. Cooper et al. (1950) observed massive nitrogen loss in male patients immediately after severe injury had been sustained by the spinal cord at levels between the 5th cervical and the 19.th thoracic segments, and for a week or two thereafter. The negative nitrogen balance amounted to 15 to 25 gm per day. Urea nitrogen constituted 80 per cent of the total urinary nitrogen. Hypoproteinemia occurred, with serum protein levels as low as 4,6 to 5,7 gm per cent. In those cases in which the urinary creatine was determined, extremely high values were obtained; in one ease the ereatine excretion exceeded 1000 mg per 9,4 hours. In the period following the acute stage creatinuria was still present, about 800 mg per day. In this period the serum proteins increased, but did not reach normal levels. When the clinical course reached a chronic stage, a positive nitrogen balance appeared; in some eases the positive balance amounted to 5 to 7 gm daily, and the ereatinuria decreased to 100 to 9,00 mg daily. Serum protein levels often remained low even when the nitrogen balance was positive.