Brain temperature protocol

Many protocols fix at 4 °C. While this decreases possible autolytic processes, transmitter/peptide release, and neuronal activity, it also leads to a slower penetration of the fixative into the tissue which counterbalances these effects. In fact, we have not found much of a difference between fixation at 4 °C (larval CNS, 2 h adult brain, 2-3 h) and at room temperature. Although given times have always worked in our hands, the fixation time can be varied, if needed. 

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