Premium
QUANTITATIVE ASPECTS OF CO 2 FIXATION IN MAMMALIAN BRAIN IN VIVO *
Author(s) -
Waelsch H.,
Berl† S.,
Rossi C. A.,
Clarke D. D.,
Purpura§ D. P.
Publication year - 1964
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1964.tb06117.x
Subject(s) - columbia university , medicine , university hospital , gerontology , psychiatry , library science , family medicine , sociology , media studies , computer science
: The data presented in this paper support the conclusion that CO2 fixation in the mammalian brain is a process which responds to the change in the metabolic environment. The rate of CO2 fixation is increased when the tissue is exposed to a metabolic stress, such as an elevated ammonia concentration, which results in an increased synthesis of glutamine. The data show that CO2 fixation is of considerable significance in brain metabolism and not negligible. It plays an essential role in maintaining the concentration of dicarboxylic acids in the citric acid cycle. The continuous removal of oxoglutarate without replenishment would lead to a breakdown of the citric acid cycle and consequently to a deficiency in the production of ATP. Although the data suggest that CO2 fixation may well replenish the intermediates of the citric acid cycle in case of increased ammonia concentration in brain tissue, these acute experiments give no answer as to the chronic effects of ammonia on the citric acid cycle.