Increased gluconeogenesis in rats exposed to hyper-G stress

Journal Article · Mon Jul 22 00:00:00 EDT 1985 · Life Sci.; (United States)

DOI:https://doi.org/10.1016/0024-3205(85)90649-6· OSTI ID:5411357

Daligcon, B C; Oyama, J; Hannak, K

The role of gluconeogenesis on the increase in plasma glucose and liver glycogen of rats exposed to hyper-G (radial acceleration) stress was determined. Overnight-fasted, male Sprague-Dawley rats (250-300 g) were injected i.p. with uniformly labeled /sup 14/C lactate, alanine, or glycerol (5 ..mu..Ci/rat) and immediately exposed to 3.1 G for 0.25, 0.50, and 1.0 hr. /sup 14/C incorporation of the labeled substrates into plasma glucose and liver glycogen was measured and compared to noncentrifuged control rats injected in a similar manner. Significant increases in /sup 14/C incorporation of all three labeled substrates into plasma glucose were observed in centrifuged rats at all exposure periods; /sup 14/C incorporation into liver glycogen was significantly increased only at 0.50 and 1.0 hr. The i.p. administration (5 mg/100-g body wt) of 5-methoxyindole-2-carboxylic acid, a potent gluconeogenesis inhibitor, prior to centrifugation blocked the increase in plasma glucose and liver glycogen during the first hour of centrifugation. The increase in plasma glucose and liver glycogen was also abolished in adrenodemedullated rats exposed to centrifugation for 1.0 hr. Propranolol, a beta-adrenergic blocker, suppressed the increase in plasma glucose of rats exposed to centrifugation for 0.25 hr. From the results of this study, it is concluded that the initial, rapid rise in plasma glucose as well as the increase in liver glycogen of rats exposed to hyper-G stress can be attributed to an increased rate of gluconeogenesis, and that epinephrine plays a dominant role during the early stages of exposure to centrifugation. 11 references, 3 tables.

• Research Organization: NASA Ames Research Center, Moffett Field, CA
• OSTI ID: 5411357
• Journal Information: Life Sci.; (United States), Vol. 37:3
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
BIOLOGICAL STRESS
BIOLOGICAL EFFECTS
GLUCOSE
BIOCHEMICAL REACTION KINETICS
GLYCOGEN
ALANINES
CARBON 14 COMPOUNDS
GLYCEROL
LACTIC ACID
LIVER
RATS
TRACER TECHNIQUES
ALCOHOLS
ALDEHYDES
AMINO ACIDS
ANIMALS
BODY
CARBOHYDRATES
CARBOXYLIC ACIDS
DIGESTIVE SYSTEM
GLANDS
HEXOSES
HYDROXY ACIDS
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
MAMMALS
MONOSACCHARIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
POLYSACCHARIDES
REACTION KINETICS
RODENTS
SACCHARIDES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques