"Gunter Kuhnle" <gunter at elnhuk.de> wrote in message
news:slrn9fd2l2.bv2.gunter at pc039-034.phrt.umds.ac.uk...
> * Richard Norman <rsnorman at mediaone.net> wrote:
> >> Your question is not quite clear : do you talk about human striatum, or
> >> other species (cat's ?) ; of an adult , I presume ?
> >> Are you looking for the volume per cell (cell volume) or looking for
the
> >> total mass of the corpus striatum (total number of cells in that
> >> structure?)
> >> The volume as such ? or the mass (in weight) ?
>> I am looking for the (average) volume of a single neuron cell in human
> striatum.
>> >I am also curious to know how you plan to use the volume of cells
> >to calculate concentrations. What data do you already have and what
> >are you trying to do? Apparently you have measured the quantity
> >(grams or moles) of some material taken from a brain sample and
> >want to calculate an appropriate concentration. But what indication
> >do you have that the material you measured was specifically
> >restricted to the intracellular volume of striatum neurons, as
> >opposed to glia or trapped in the extracellular space? Those
> >factors are critical in determining what volume to use.
>> We didn't use brain but cell cultures to do our investigations. To get
> the amount of compound uptaken by the cells, the cells could be lysed
> with a certain amount of lysing buffer in which the compound
> concentration could be determined. Unfortunately, without knowing the
> cell volume it is impossible to obtain the concentration in cell.
>> But for this reason, it es really only the volume inside the cells
> relevant for the calculation.
>
You could, of course, measure the size of the cells and calculate
a volume from that. Or you could load them with, say, labeled K+
-- anything for which you could reasonable calculate or estimate
in intracellular concentration. Then when you lyse them, the
concentration of labeled K+ in the lysate would give you the
information you need.