Adenosine enhances neuronal damage during deprivation of oxygen and glucose in guinea pig superior collicular slices.
The purpose of the present study was to clarify whether adenosine has a neuroprotective effect against neuronal damage during deprivation of oxygen and glucose in superior collicular slices. After deprivation of oxygen and glucose for 7 min, the concentration of ATP in slices incubated with adenosine (100 microM) for 60 min was significantly higher (6.43 +/- 0.16 nmol/mg protein, mean +/- S.E.M.) than that in slices incubated without adenosine (4.77 +/- 0.61). The postsynaptic field potential (PSP) recorded in the superficial gray layer of the SC slice completely disappeared within 7 min after deprivation of oxygen and glucose and it recovered to approximately 80% of the original amplitude in the medium without adenosine. But, in the presence of adenosine (100 microM) during and after oxygen and glucose removal, the PSP showed only approximately 40% recovery. These results indicate that in the superior colliculus adenosine has no protective effect on functional derangement caused by anoxia although it may facilitate the resynthesis of tissue ATP during recovery.
Fujiwara
F
F
Department of Physiology, School of Medicine, Kobe University, Japan.
Hirai
H
H
Tamaki
N
N
Okada
Y
Y
D000200:Action Potentials / Q000187:drug effects*; D000241:Adenosine / Q000494:pharmacology*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D004305:Dose-Response Relationship, Drug; D006168:Guinea Pigs; D000860:Hypoxia; D009474:Neurons / Q000378:metabolism*; D013477:Superior Colliculi / Q000187:drug effects*
D000255:Adenosine Triphosphate; D000241:Adenosine