Relationships between energy reserves and function in rat superior cervical ganglion.

Abstract

Abstract—Major components of the energy reserves of the isolated superior cervical ganglion (ATP, phosphocreatine, glucose, glycogen and lactate) were measured under aerobic and anaerobic conditions. Complete anaerobiosis was maintained by incubation in mineral oil through which N2 had been bubbled. From the initial rate of change in the energy reserves, a metabolic rate was calculated which would be equivalent to the consumption of 93 m‐moles of O2 per kg per hour. Under aerobic conditions (oxygenated moist chamber) a similar metabolic rate was calculated. In contrast to the anaerobic state, initial energy expenditure was almost exclusively at the expense of glucose. Continuous supramaximal stimulation in O2 increased energy expenditure by a factor of three; both glucose and glycogen were utilized from the outset, and lactate accumulated in the initial periods.Ganglionic transmission failed in both resting and stimulated states in spite of the continued presence of very substantial levels of ATP and phosphocreatine. Failure seemed to be associated not with ATP depletion but rather with the complete disappearance of glucose and glycogen.