Propofol causes neurite retraction in neurons
2008 (English)In: British Journal of Anaesthesia, ISSN 0007-0912, E-ISSN 1471-6771, Vol. 101, no 3, 374-379 p.Article in journal (Refereed) Published
Background The mechanism by which anaesthetic agents produce general anaesthesia is not yet fully understood. Retraction of neurites is an important function of individual neurones and neural plexuses during normal and pathological conditions, and it has been shown that such a retraction pathway exists in developing and mature neurones. We hypothesized that propofol decreases neuronal activity by causing retraction of neuronal neurites.
Methods Primary cultures of rat cortical neurones were exposed in concentration– and time–response experiments to 0.02, 0.2, 2, and 20 µM propofol or lipid vehicle. Neurones were pretreated with the GABAA receptor (GABAAR) antagonist, bicuculline, the myosin II ATPase activity inhibitor, blebbistatin, and the F-actin stabilizing agent, phalloidin, followed by administration of propofol (20 µM). Changes in neurite retraction were evaluated using time-lapse light microscopy.
Results Propofol caused a concentration- and time-dependent reversible retraction of cultured cortical neurone neurites. Bicuculline, blebbistatin, and phalloidin completely inhibited propofol-induced neurite retraction. Images of retracted neurites were characterized by a retraction bulb and a thin trailing membrane remnant.
Conclusions Cultured cortical rat neurones retract their neurites after exposure to propofol in a concentration- and time-dependent manner. This retraction is GABAAR mediated, reversible, and dependent on actin and myosin II. Furthermore, the concentrations and times to full retraction and recovery correspond to those observed during propofol anaesthesia.
Place, publisher, year, edition, pages
Oxford, UK: Oxford University Press, 2008. Vol. 101, no 3, 374-379 p.
Anaesthetics i.v., propofol; brain, GABA rat; theories of anaesthetic action, cellular mechanisms
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-78010DOI: 10.1093/bja/aen185ISI: 000259093300014OAI: oai:DiVA.org:liu-78010DiVA: diva2:530766