Artificial Cerebrospinal Fluid Protocols Published in 2020

Science
1

We have been using the method from Ting 2018 for aCSF solutions and recently found ACSF I-IX. I assume ACSF I, IV, and IX, correspond to perfusion/cutting/recovery, holding, and recording for mouse brain slices. These seem to be a more updated version of prep. So my questions are:

  1. Is there a publication talking about these aCSF preps, like the rational of adding taurine, N-acetylcysteine, and Myo inositol?
  2. In Ting 2018 paper, they recommended a gradual sodium spike during recovery. That was not mentioned in the 2020 protocols. Is that still recommended?
  3. Can’t find the protocol for ACSF II. I’d appreciate any information on the applicability of that.

Thanks!

2

Hi @RosalindWYZ42, thanks for your message. Please see our protocols.io linked here ( Patch-Seq Recording and Extraction Detailed Protocol), specifically table 2 for ACSF recipes. Regarding the taurine, N-AC and Myo, we don’t have publications with the rationale but there is plenty of literature suggesting their neuroprotective, cell/slice health, etc. Regarding the Na+ spike in, this is something that we do not do as part of our standardized protocol. We don’t currently use ACSF II. Table II in the linked protocol lists the current active ACSF recipes. Please let me know if there is any other questions I can answer.

3

Thank you so much :slight_smile:

4

In ACSF. IV NaCl concentration is listed as 84 mM, but in all other documents referencing ACSF. IV, the concentration is listed as 94 mM. Also, I don’t think the amount of NaCl needed as written in ACSF.IV correspond to either 84 or 94 mM. Would you please confirm this?
Also, I am having trouble understanding the formula to add NaCl when the osmolarity is too low (8.5). Is X supposed to be mg salt per ml ACSF solution? From the way it is described, it seems like I should prepare NaCl solution with a concentration of 1mg/1mL, which will be directly added to the ACSF solution to correct osmolarity. However that is quite a low concentration of saline solution with low osmolarity and I failed to see how that can raise the osmolarity of ACSF solution.
@brian_lee Thank you so much for your help!!

5

Hi, in the table attached, for ACSF.14 we use 92 or 94 mM NaCl (mouse, human, respectively). ACSF.IV is the incubation ACSF and ACSF.III is the recording solution which has a NaCl concentration is 126 mM. Is ACSF.III the solution you are looking for?

6

Thanks for the clarification. I am referring to the protocol for ACSF IV (Artificial Cerebrospinal Fluid IV (ACSF.IV)). Here NaCl is listed as 84 mM