CNO in drinking water

We frequently get requests regarding protocols for putting CNO in the drinking water for long-term studies.

Here is our protocol:

1. Dissolve the CNO in a small volume of DMSO
2. Diluted the dissolved CNO in drinking water (e.g., 5mg/200ml)
3. Give mice with CNO drinking water  and protect from light using foil-wrapped bottles
4. The mice will receive 5mg/kg/day CNO (assume that mice weight 30g and consume 6ml water per day)

5. Prepare fresh daily.
6. A small amount of saccharine in the drinking water will mask the slightly bitter taste of CNO

Comments

  1. Hi, I am giving the CNO through drinking water to the mouse. I use syringe to give CNO solution to head-fixed mice. How long should I wait to do the behavioral test after the CNO delivery? I have tried 1 hr, however, the result is quite variable.
    Thanks,
    Lupeng

    ReplyDelete
    Replies
    1. Hi Roger:
      We've published detailed pharmacokinetic data on peripheral CNO administration and plasma CNO levels here:
      http://www.pnas.org/content/suppl/2009/10/26/0906593106.DCSupplemental/Appendix_PDF.pdf

      Mouse brain CNO pharmacokinetic data done with 11C-CNO can be found here and is similar to plasma CNO:

      Nuclear Medicine and Biology
      Volume 21, Issue 7, October 1994, Pages 921–925

      Normally what we do is a time-course study as shown Neuron. Jul 16, 2009; 63(1): 27–39 in transgenic mice before doing viral transduction studies of the cell-type of interest.

      Hope this helps,
      Bryan

      Delete
  2. Hi,

    how much saccharin do you add to the drinking water?

    Thanks,
    Christin

    ReplyDelete
  3. We have feedback from users who have successfully used 5 mM saccharin

    ReplyDelete
  4. Have drinking water mediated CNO delivery been used in rats? If so, what doses have been used ?

    Thanks in advance,

    Prabahan

    NCBS, India

    ReplyDelete
  5. I'm not aware of anyone who has done this in rats but there is no reason to think it would not work well in rats

    ReplyDelete
  6. Hi,

    can CNO be administered by drinking water to a nursing mother in order to treat its pups until their weaning?

    Thanks in advance,

    Andrea

    ReplyDelete
  7. In theory yes though I haven't seen any papers on this. You would likely need to do controls measuring CNO in pups brains

    ReplyDelete
  8. Hello,

    Can anyone comment on their final concentration of DMSO in drinking water? I've tried 0.25% but have found some mice are still reluctant to drink it. I'd prefer to avoid saccharine for experimental reasons.

    Thanks very much,

    Chris

    ReplyDelete
  9. Hello,

    Is it standard practice to administer the saccharin containing water prior to the actual CNO administration (for habituation purposes)?

    Thank you,

    Amrita

    ReplyDelete
  10. Hi,

    did you find some differences in terms of efficiency between CNOs coming from different companies? I am finding different effects at same dosages between Sigma vs Enzo Life Science in vivo.

    Thank you in advance

    Andrea

    ReplyDelete
  11. May I ask why the concentration of oral CNO is higher than i.p administration? Based on previous papers high concentration of CNO can induce seizure. Is the different in oral and ip concentration is due to bio-availability?

    ReplyDelete
  12. CNO alone does not induce seizures (don't know why you think this might be true). Oral bioavailability is lower than from ip injection, however.

    ReplyDelete
    Replies
    1. This comment has been removed by the author.

      Delete
  13. Is there any available data on how reduced oral bioavailability is compared to i.p.?

    ReplyDelete
  14. is CNO subcutaneous injection better than ip injection in terms of stress?

    ReplyDelete
  15. This comment has been removed by the author.

    ReplyDelete

Post a Comment

Popular posts from this blog

Update on AAVs for DREADDs