Voltage sensitive dye imaging of transient neuronal assemblies in brain slices under hyperbaric conditions.
We have developed a high pressure optical cell to study large-scale transient neuronal coalitions--"assemblies" using voltage sensitive dye (VSD) fluorescence combined with fast CCD imaging of brain slices under hyperbaric conditions. The new cell has been tested at pressures up to P = 150-200 atm, corresponding to the range over which effects such as "pressure-reversal" of anaesthesia have been described previously. Brain slices were maintained in a flow of artificial cerebrospinal fluid (aCSF) and hyperbaric conditions were controlled to within +/- 0.2 atm using a back-pressure regulator placed in the pumping system. Preliminary VSD imaging experiments were carried out on rat hippocampal slices at pressures up to P approximately 50 atm. An electrode placed in the CA3 region was used to stimulate a signal along the Schaffer collateral towards CA1. First results indicate that good VSD data can be obtained that can be analysed to provide a new view on how hydrostatic pressurisation affects the dynamic propagation of neuronal assemblies.
Wlodarczyk
A
A
Department of Chemistry and Materials Chemistry Centre, Christopher Ingold Laboratories, University College London, 20 Gordon Street, London WC1H 0AJ, UK.
McMillan
P F
PF
Greenfield
S A
SA
D000818:Animals; D001273:Atmosphere Exposure Chambers; D002555:Cerebrospinal Fluid; D004558:Electric Stimulation / Q000379:methods; D004867:Equipment Design / Q000379:methods; D005453:Fluorescence; D005456:Fluorescent Dyes; D006624:Hippocampus / Q000502:physiology*; D006874:Hydrostatic Pressure; D008297:Male; D009474:Neurons / Q000502:physiology*; D051381:Rats
D005456:Fluorescent Dyes