Purine release and inhibition of synaptic transmission during hypoxia and hypoglycemia in rat hippocampal slices

p38 Mitogen-Activated Protein Kinase Contributes to Adenosine A1Receptor-Mediated Synaptic Depression in Area CA1 of the Rat Hippocampus

“…Hypoxia releases adenosine into the extracellular space (Fowler, 1993;Dale et al, 2000), where it activates A 1 receptors. During extended periods of hypoxia, adenosine release contributes to ϳ50% of the hypoxia-induced synaptic depression (Fowler, 1989).…”

Temperature-Dependent Modulation of Excitatory Transmission in Hippocampal Slices Is Mediated by Extracellular Adenosine

“…However, a variety of situations can increase extracellular adenosine levels dramatically and virtually abolish excitatory synaptic transmission. Most of the conditions known to promote such large increases in extracellular adenosine are those in which the supply of oxygen and energy substrates is not adequate to meet the energy demands of the brain, such as hypoxia (Rubio et al, 1975;Fowler, 1993;Z hu and Krnjević, 1993), ischemia (Berne et al, 1974), metabolic inhibition (Z hu and Krnjević, 1997), or electrical hyperactivity (Rubio et al, 1975;L loyd et al, 1993). All of these conditions ultimately can become pathological and result in significant cell loss.…”

“…A common aspect of many stimuli that release adenosine from brain slices is a reduction in the ability of cells to synthesize ATP (e.g., by removing glucose or oxygen from the superfusion buffer) (Fowler, 1993;Zhu andKrnjević, 1993, 1997). Another manipulation that might alter metabolic balance and be physiologically stressful is changing the temperature.…”

Ketone Strong: Emerging evidence for a therapeutic role of ketone bodies in neurological and neurodegenerative diseases

“…Hypoglycemia is well-known to release adenosine ( 43 ), which would have driven the input/output curve downward compared with slices incubated in 11 mM glucose; such a change in the curve did not occur. Slices incubated in 3 mM glucose (and 11 mM) remained similarly recordable and thus apparently healthy out to our maximum slice recovery time of 5 h. In a previous study using identical slicing and recording conditions in the identical hippocampal substructure (in tissue from CD-fed animals), we presented data inferring that adenosine tone at A 1 Rs was similar in 3 mM and 11 mM glucose.…”