Neural Pathways Mediating the Increase in Adrenal Medullary Secretion Produced by Hypoglycemia.

Abstract

Summary Insulin-induced hypoglycemia produced a marked increase in epinephrine secretion in fasted dogs. The rise was not abolished by transection of the midbrain or cervical spinal cord. It was completely abolished by removal of the thoracic and upper lumbar spinal cord in 4 of 6 dogs studied. It was also blocked by localized resection of the fifth to seventh thoracic segments of the spinal cord, but not by removal of more caudal segments. These data indicate that the portion of the spinal cord above the seventh thoracic segment is the only part of the central nervous system which is essential in the dog for the increase in epinephrine secretion produced by insulin-induced hypoglycemia.