Dear Garret Vincent;

you can use TMRM to measure in vivo mitochondrial membrane potential. As Mr Ali Abdil Razzaq Muhammed Noori Aldallal linked several papers are already published using this approach. the problem in the "in vivo mitochondrial membrane potential measurement" is linked with the microscope. if you have an appropriate microscope you shouldn't have any problem .

regards,

Francesco 

Dear Garret,

Helena Cocheme 's group is currently developping a probe for measuring the membrane potentiel in vivo.

The principal is the same than their previous probe to measure the ROS production in vivo (Cf Cocheme, Helena M., Caroline Quin, Stephen J. McQuaker, Filipe Cabreiro, Angela Logan, Tracy A. Prime, Irina Abakumova, Jigna V. Patel, Ian M. Fearnley, Andrew M. James, Carolyn M. Porteous, Robin A. J. Smith, Saima Saeed, Jane E. Carre, Mervyn Singer, David Gems, Richard C. Hartley, Linda Partridge and Michael P. Murphy. "Measurement of H2o2 within Living Drosophila During Aging Using a Ratiometric Mass Spectrometry Probe Targeted to the Mitochondrial Matrix." Cell Metabolism 13, no. 3 (2011): 340-350.). 

It involves the sacrifice of the organism / cell to extract the probe but it is a true measurement of in vivo parameters. 

So far I know, Helena 's group is still developing the probe but you might want to contact her directly. Really promising method. 

Best wishes 

Karine

Dear Garret: Happy New Year!

The colleagues above my pos gave you good and valuable advices how to measure in vivo mitochondrial membrane potential/ Now a few words about interpretation of those data. You have to understand that evaluation of the mitochondrial MP with various fluorescent probes is only qualitative. You cannot assign any numbers in mV.

You also have to consider the conditions of the cell's environment, oxygen supply, etc. From this it is clear that you can compare the data only withing the same object (MP goes up or down) and cannot make any comparisons with other cells, organs, etc.

Dear Garret,

Thank you for posting the question, I had the same question and the answers above have been extremely helpful. I would like to share one more article if this helps

http://imaging.onlinejacc.org/article.aspx?articleid=1208327

Authors have used a PET tracer for measuring mitochondrial membrane potential. This can be more quantitative but has lower resolution than the method mentioned in Kidney International article.

 Hi Garret!

I need help with determining mitochondrial membrane potential with TMRE. Which technique do you use in vitro, flow cytometry, fluorescent microscopy or microplate reader?  I am trying to determine mitochondrial membrane potential using TMRE with a plate reader but the protocol I got from abcam is not working. Simply, it is to incubate cells in 96-well plate with 500nM of TMRE for 30 minutes followed by a couple of washes with PBS having 0.2 % BSA, then measuring the fluorescence at 549/575 nm but I get higher fluorescence from the blank wells (PBS + 0.2% BSA) than the cells treated with TMRE. I previously used florescent microscopy and it worked. Do you have anything to recommend.

Thanks.