Energy metabolism of dogs after total destruction of the central nervous system

¹ Department of Physiology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil

The central nervous system of male adult dogs was destroyed by an injection in the cisterna magna, of a 20% NaCl solution, under 60 cm Hg pressure, during 6 min (technique of Galvão and Pereira). One hundred and sixteen O₂ consumption determinations were made by analysis of the expired air or of the air pumped through the lungs, in 28 dogs, before and after CNS destruction. The metabolism level was generally well maintained during the first hours after the destruction and was materially unaltered in some dogs until death. However, in many dogs the heat production decreased more or less gradually in the later hours, and attained a mean lowering of 16.8%. The anesthesia employed, the abolition of muscle tonus and work of respiratory muscles, the respiration of the CNS, and the loss of a trophic or metabolic action of the CNS are discussed in an attempt to explain the metabolic rate of animals deprived of CNS.