Phorbol ester alters the electrophysiological responses to hypoxia and ischemic-like conditions in the rat hippocampal slice.
The effect of incubation with the protein kinase C activator, 4 beta-phorbol 12,13-dibutyrate (beta-PDBu) on the electrophysiological responses to hypoxia and combined hypoxia and hypoglycemia was investigated in the rat hippocampal slice. Preincubation with beta-PDBu prevents adenosine-mediated inhibition of synaptic transmission under normoxic, normoglycemic conditions. beta-PDBu preincubation also reduces the adenosine-mediated hypoxia-induced depression of synaptic transmission revealing a substantial adenosine-independent hypoxia-induced depression of synaptic transmission. During combined hypoxia and hypoglycemia, slices preincubated in beta-PDBu display a significant shortening of the time of anoxic depolarization, an effect of beta-PDBu that is not mimicked by application of the adenosine antagonist cyclopentyltheophylline (8-CPT). It is concluded that the state of PKC activation may influence the electrophysiological responses to hypoxia and ischemia.
Fowler
J C
JC
Department of Physiology, Texas Tech Health Sciences Center, Lubbock 79430, USA.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002545:Brain Ischemia / Q000188:drug therapy* / Q000503:physiopathology; D004789:Enzyme Activation; D006624:Hippocampus / Q000187:drug effects* / Q000502:physiology; D002534:Hypoxia, Brain / Q000188:drug therapy* / Q000503:physiopathology; D066298:In Vitro Techniques; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology*; D011493:Protein Kinase C / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D009435:Synaptic Transmission / Q000187:drug effects*
D015240:Phorbol 12,13-Dibutyrate; D011493:Protein Kinase C