Depletion of ATP and release of presynaptic inhibition in the CA1 region of hippocampal slices during hypoglycemic hypoxia.
Transient recovery (TR) of evoked synaptic potentials and ATP depletion during the late stage of hypoxic hypoglycemic insults were investigated in rat hippocampal slices. TR was observed not only in the late stage of insult, but also during recovery. The concentration of ATP corresponded to the appearance (27% of control) and disappearance (15% of control) of TR. Paired pulse studies showed the presynaptic nature of the release of inhibition of synaptic transmission during TR. Both N- and P/Q-type voltage-dependent calcium channels were involved in the appearance of TR. This evidence suggests that underlying mechanisms of TR appearance during hypoxic hypoglycemic insult might be related to ATP depletion and release of A1 adenosine receptor mediated inhibition of presynaptic voltage-dependent calcium channels.
Kim
Jong-Hyun
JH
Department of Neurosurgery, Korea University Guro Hospital, 80 Guro-dong, Guro-ku, Seoul 152-703, South Korea.
Kim
Jae-Hak
JH
Kim
Joo-Han
JH
Kim
Kyung-Han
KH
Kwon
Taek-Hyun
TH
Park
Youn-Kwan
YK
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology; D004347:Drug Interactions; D004558:Electric Stimulation / Q000379:methods; D006624:Hippocampus / Q000503:physiopathology*; D007003:Hypoglycemia / Q000473:pathology*; D066298:In Vitro Techniques; D053444:Inhibitory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D008297:Male; D017729:Presynaptic Terminals / Q000187:drug effects / Q000502:physiology*; D058915:Purinergic P1 Receptor Antagonists; D051381:Rats; D017207:Rats, Sprague-Dawley; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D014970:Xanthines / Q000494:pharmacology; D020866:omega-Conotoxin GVIA / Q000494:pharmacology
D002121:Calcium Channel Blockers; D058915:Purinergic P1 Receptor Antagonists; D014970:Xanthines; D000255:Adenosine Triphosphate; D020866:omega-Conotoxin GVIA; C051360:1,3-dipropyl-8-cyclopentylxanthine