adipose stains? - specific stain to positively ID adipose cells (Jul/04/2007 )

hi. i would like to ask what stains are out there to positively identify adipose cells, mostly brown fat? thanks.

Usually fat cells in tissue section can be identified by strictly morphological criteria: a lipid vesicle/vacuole which occupies majority of cell volume. Lipophilic stains can also be used, such as Oil-red-O or Sudan Black B, which stain lipids such as those in the vesicle/vacuole; I prefer oil-red-O for cell preps, and I see that Sudan black is used more frequently for frozen tissue sections. I guess it depends on your tissue/cell prerarations.

Tissues/cells destined for these stains cannot be exposed to alcohols,xylenes or acetone, or most detergents as these dissolve the lipid. If you are doing cells grown in monolayer or cytospin, you can fix them by exposure to formalin fumes - simply soak a gauze pad in formalin and place the slides/coverslip over the pad in a closed container for an hour or so. Lipid staining in tissues pretty much has to be done on frozen sections.

Also you can differentiate brown vs. white fat by staining for mitochondria with MitoTracker red or other various Mt stains

I was looking at slides of fat cells just last night (telly must have been dull). I also remember seeing the expression "cygnet ring morphology" years ago. I just can't remember if that's the expression used to describe adipocytes. Any clever clogs out there that can put me out of my confusion?