Gunter Kuhnle wrote:
>> * 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.
>
If you can pellet the cells before lysis you can estimate
the internal volume experimentally with [3H] water and
[14C]inuline (or other non-permeant and non-binding
compound). Just measure [3H] (total volume) and 14C
(external) in the supernatant and pellet, and you can
estimate the amount of external water trapped in the pellet,
i.e. the true internal water.
Enrique
