peritoneal fluid dilution - (Mar/02/2010 )

hi all

i had to collect the peritoneal fluid from normal control mice, but since it was difficult to collect the fluid from live mice, i injected 2 ml of normal saline into the cavity and inturn i got 1 ml of peritoneal fluid (from the test mice with peritoneal inflammation it is not difficult to collect the peritoneal fluid). i did NO estimation in the fluid by a biochemical method. now i am getting problem in calculation...what would be the dilution factor for the sample?

please help!!!

I would apply no dilution factor, you can't compare your control mice direct with the test mouse because you cant tell'how the extra volume production off the fluid influence the results. Just write exactly in your publication under methods what has been done.

I have another concern, if you are working with animals prepare your experiments very carefully. I think you behavior is ethically not very decent when you have to repeat the experiment because you didn't think it over very carefully.

thank you Gerard for the answer...i didn't know it is ethically wrong to take out peritoneal fluid from the live mice..now i'll collect the fluid at the time of dissection after sacrificing it by cervical dislocation...then i may not need to inject saline in the cavity and would know approx amount of fluid in the cavity...but if i don't use the dil. factor would my data be accepted for the publication?

Gerard on Mar 2 2010, 02:14 PM said:

As long as you handle both types of animals in the same fashion. Flush the cavities of both with saline. The volume of fluid is probably not the major item of interest...it is probably the protein or agent that is in the fluid. I imagine you have to purify or quantify the 'contents' of the fluid be it cells, antibody etc.