Biomaterial Database

Effect of helium and heliox on glutamate decarboxylase activity. 1990

J S Colton, and S C Gilman, and P Chang, and C A Colton

Diving Medicine Department, Naval Medical Research Institute, Bethesda, Maryland 20814-5055.

The activity of glutamate decarboxylase (GAD) in pure helium at 6.8 MPa was significantly enhanced when compared to GAD activity in air at 0.1 MPa (906 vs. 602 nmol.h-1.mg-1 protein, respectively). No significant difference was found between GAD activities in heliox at 6.8 MPa (0.87% O2 at 6.8 MPa) and in air at 0.1 MPa. On the other hand, the activities in heliox at 0.1 MPa (0.87% O2 at 0.1 MPa) and air at 0.1 MPa were significantly different (655 and 446 nmol.h-1.mg-1 protein, respectively). These data indicate that pressures up to 6.8 MPa do not affect the GAD-catalyzed synthesis of gamma-aminobutyric acid, but that the enzyme, as previously reported, is sensitive to low levels of oxygen.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D010100	Oxygen	An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.	Dioxygen,Oxygen-16,Oxygen 16
D003509	Cyclohexanecarboxylic Acids	Carboxylic acid derivatives of cyclohexane.	Acids, Cyclohexanecarboxylic
D005680	gamma-Aminobutyric Acid	The most common inhibitory neurotransmitter in the central nervous system.	4-Aminobutyric Acid,GABA,4-Aminobutanoic Acid,Aminalon,Aminalone,Gammalon,Lithium GABA,gamma-Aminobutyric Acid, Calcium Salt (2:1),gamma-Aminobutyric Acid, Hydrochloride,gamma-Aminobutyric Acid, Monolithium Salt,gamma-Aminobutyric Acid, Monosodium Salt,gamma-Aminobutyric Acid, Zinc Salt (2:1),4 Aminobutanoic Acid,4 Aminobutyric Acid,Acid, Hydrochloride gamma-Aminobutyric,GABA, Lithium,Hydrochloride gamma-Aminobutyric Acid,gamma Aminobutyric Acid,gamma Aminobutyric Acid, Hydrochloride,gamma Aminobutyric Acid, Monolithium Salt,gamma Aminobutyric Acid, Monosodium Salt
D005968	Glutamate Decarboxylase	A pyridoxal-phosphate protein that catalyzes the alpha-decarboxylation of L-glutamic acid to form gamma-aminobutyric acid and carbon dioxide. The enzyme is found in bacteria and in invertebrate and vertebrate nervous systems. It is the rate-limiting enzyme in determining GAMMA-AMINOBUTYRIC ACID levels in normal nervous tissues. The brain enzyme also acts on L-cysteate, L-cysteine sulfinate, and L-aspartate. EC 4.1.1.15.	Glutamate Carboxy-Lyase,Glutamic Acid Decarboxylase,Acid Decarboxylase, Glutamic,Carboxy-Lyase, Glutamate,Decarboxylase, Glutamate,Decarboxylase, Glutamic Acid,Glutamate Carboxy Lyase
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D006371	Helium	A noble gas with the atomic symbol He, atomic number 2, and atomic weight 4.003. It is a colorless, odorless, tasteless gas that is not combustible and does not support combustion. It was first detected in the sun and is now obtained from natural gas. Medically it is used as a diluent for other gases, being especially useful with oxygen in the treatment of certain cases of respiratory obstruction, and as a vehicle for general anesthetics.	Helium-4,Helium 4
D006610	High Pressure Neurological Syndrome	A syndrome related to increased atmospheric pressure and characterized by tremors, nausea, dizziness, decreased motor and mental performance, and SEIZURES. This condition may occur in those who dive deeply (c. 1000 ft) usually while breathing a mixture of oxygen and helium. The condition is associated with a neuroexcitatory effect of helium.	Experimental High Pressure Neurological Syndrome,HPNS,High Pressure Nervous Syndrome,High Pressure Neural Syndrome,High Pressure Neurological Syndrome, Experimental,HPNSs
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001274	Atmospheric Pressure	The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.	Atmospheric Pressures,Pressure, Atmospheric,Pressures, Atmospheric