Phorbol ester alters rat hippocampal neuronal response to hypoxia.
The effect of the protein kinase C (PKC) activator, 4 beta-phorbol-12, 13-dibutyrate (beta-PDBu) on electrophysiological properties of rat hippocampal CA1 neurons exposed to moderate hypoxia was examined. Hypoxic beta-PDBu-pretreated neurons differed from untreated neurons by exhibiting an adenosine-independent loss of synaptic transmission, an apparent large increase in injected threshold current necessary to elicit an action potential, an increase rather than a decrease in membrane resistance, and an increase rather than a decrease in hyperpolarizing holding current. Additional experiments with an adenosine A1 antagonist suggest that beta-PDBu alters neuronal responses to hypoxia through some mechanism other than the documented ability of beta-PDBu to uncouple the A1 receptor.
Liu
Z W
ZW
Department of Physiology, Texas Tech University Health Sciences Center, Lubbock 79430, USA.
Fowler
J C
JC
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects*; D000860:Hypoxia / Q000378:metabolism*; D008297:Male; D010703:Phorbol Esters / Q000494:pharmacology*; D011493:Protein Kinase C / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley
D010703:Phorbol Esters; D011493:Protein Kinase C