Brain glucose

Chafetz, M. D., Parko, K., Diaz, S. Leibowitz, S. F. (1986). Relationships between medial hypothalamic alpha 2-receptor binding, norepinephrine, and circulating glucose. Brain Res. 384, 404-8. 

Since the brain utilizes energy almost exclusively from oxidative metabolism of glucose, brain metabolism has been studied by focusing on net oxygen and glucose uptake. Oxygen consumption was classically measured as the arteriovenous difference of 02 content. When a substance is exchanged between brain and blood, the difference between its steady state of delivery to brain in the arterial blood and removal in the venous blood must be equal to the net rate of its utilization or... 

Ritter S, Dinh TT, Zhang Y. 2000. Localization of hindbrain glucoreceptive sites controlling food intake and blood glucose. Brain Res 856 37-47. 

Leibowitz, S.F., Sladek, C., Spencer, L. Tempel, D. (1988) Neuropeptide Y, epinephrine and norepinephrine in the paraventricular nucleus stimulation of feeding and the release of corticosterone, vasopressin and glucose. Brain Res. Bull. 21, 905-912. 

H (D) D2O, methionine, glucose Brain, adipose tissue, liver... 

D-galactose, C HiiOe. Crystallizes in the pyranose form m.p. 1I8-120 C (monohydrate), 165-5" C (anhydrous). An isomer of glucose which is fairly widely distributed in plants. It is a constituent of raffinose and slachyose, of hemicelluloses, of pectin, of gums and mucilages, and of some glycosides. In animals it forms half the lactose molecule and is the sugar found in the brain. Chemically it is very similar to glucose. It has the structure... 

CCK is found in the digestive tract and the central and peripheral nervous systems. In the brain, CCK coexists with DA. In the peripheral nervous system, the two principal physiological actions of CCK are stimulation of gaU. bladder contraction and pancreatic enzyme secretion. CCK also stimulates glucose and amino acid transport, protein and DNA synthesis, and pancreatic hormone secretion. In the CNS, CCK induces hypothermia, analgesia, hyperglycemia, stimulation of pituitary hormone release, and a decrease in exploratory behavior. The CCK family of neuropeptides has been impHcated in anxiety and panic disorders, psychoses, satiety, and gastric acid and pancreatic enzyme secretions. 

Hepoxylins are metabolites of arachidonic acid which arise from 12-HPETE in tissues such as pancreatic islet cells (where they stimulate glucose-dependent insulin release) and brain (where they appear to have a neuromodulatory role). The structure of the hepoxylins was confirmed by synthesis which also has provided this scarce material for biological investigation. 

The first hormonal signal found to comply with the characteristics of both a satiety and an adiposity signal was insulin [1]. Insulin levels reflect substrate (carbohydrate) intake and stores, as they rise with blood glucose levels and fall with starvation. In addition, they may reflect the size of adipose stores, because a fatter person secretes more insulin than a lean individual in response to a given increase of blood glucose. This increased insulin secretion in obesity can be explained by the reduced insulin sensitivity of liver, muscle, and adipose tissue. Insulin is known to enter the brain, and direct administration of insulin to the brain reduces food intake. The adipostatic role of insulin is supported by the observation that mutant mice lacking the neuronal insulin receptor (NDRKO mice) develop obesity. 

Central control of glucose homeostasis critically depends on the brain s ability to sense extracellular [glucose]. Within hypothalamus at least two types of neurons were identified which are presumably involved in this process. They are either glucose excited or glucose inhibited. Both types of neurons appear to be involved in the control of feeding, hepatic gluconeogenesis,... 

The blood-brain barrier (BBB) forms a physiological barrier between the central nervous system and the blood circulation. It consists of glial cells and a special species of endothelial cells, which form tight junctions between each other thereby inhibiting paracellular transport. In addition, the endothelial cells of the BBB express a variety of ABC-transporters to protect the brain tissue against toxic metabolites and xenobiotics. The BBB is permeable to water, glucose, sodium chloride and non-ionised lipid-soluble molecules but large molecules such as peptides as well as many polar substances do not readily permeate the battier. 

P2Y14 Placenta, adipose tissue, stomach, intestine, discrete brain regions UDP glucose = UDP-galactose Gq/Gu... 

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