Details

Autor(en) / Beteiligte

• Himmelseher, Sabine
• Pfenninger, Ernst
• Georgieff, Michael

Titel

The Effects of Ketamine-Isomers on Neuronal Injury and Regeneration in Rat Hippocampal Neurons

Ist Teil von

• Anesthesia and analgesia, 1996-09, Vol.83 (3), p.505-512

Ort / Verlag

Hagerstown, MD: International Anesthesia Research Society

Erscheinungsjahr

1996

Quelle

MEDLINE

Beschreibungen/Notizen

• There is a difference in the relative anesthetic potency of the isomers of ketamine.Neuroprotective differences may therefore also exist. After an 8-min exposure to 500 micro Meter glutamate or axonal transection, cultured rat hippocampal neurons were maintained untreated or in the presence of ketamine-racemate, S(+)-ketamine, or R(-)-ketamine (10 M, 10 M, 10 M). Cell survival was examined by dye inclusion/esterase activity, morphology by phase contrast and immunofluorescence microscopy, and [() H]arachidonic acid (ARA) release by liquid scintillation spectrometry. Seven days after glutamate exposure, survival decreased to 30% in the damaged, untreated group. Extracellular [() H]ARA increased fivefold. Dendritic length and branching decreased to a quarter and axonal extensions to the half. Ketamine-racemate 10 M increased survival to 65%, and induced longer dendrites (P <or=to 0.05). S(+)-Ketamine 10 M increased survival to 80%, reduced [() H]ARA threefold, and preserved cytoskeletal arborizations (P <or=to 0.05). Axotomy decreased survival to 60% and caused a minor increase in [() H]ARA after 7 days. Survival was 80% after 10 M ketamine-racemate and 90% after 10 M S(+)-ketamine (P <or=to 0.05). Only S(+)-ketamine supported axonal reoutgrowth and decreased [() H]ARA (P <or=to 0.05). R(-)-Ketamine was ineffective after both types of injury. Ketamine-racemate and S(+)-ketamine attenuated injury after glutamate exposure or axonal transection in hippocampal neurons in vitro. Neuroregenerative effects were uniquely demonstrated by S(+)-ketamine.(Anesth Analg 1996;83:505-12)