"Kalman Rubinson" <kr4 at nyu.edu> skrev i melding
news:36qd4u8j3tn0qdc597dfndcb4pa0257sr4 at 4ax.com...
> On Thu, 17 Jan 2002 22:27:55 +1300, "yan king yin" <y.k.y@(dont
> spam)lycos.com> wrote:
>> >Sorry -- I have made a mistake by extrapolating too much. I thought
> >if dopamine neurons were transplanted to the substantia nigra they
> >would project to the putamen (their normal target). But it turns out this
> >might not actually happen.
>> I do not know of this happening. The human procedures I heard of
> involved implanting the DA neurons in the the putamen so they need not
> have to find their way there.
>> >In another study by Bjorklund, they showed that embryonic DA cells
> >transplanted to the substantia nigra will reconnect with the striatum if
> >it is done in young rats (postnatal day 10) but not older (P20). Could
> >it be that the molecular cues for axonal guidance are still secreted by
> >the targets in P10 but no longer in P20? That would be bad news =(
>> It may be since it is likely that there's more than one cue involved
> in such a complex projection.
How about reproducing those cues, locally of course.
A viral vector could in theory reprogramme certain glial-cells to secrete those cues,
but that supposes extensive mapping not only of neurons, but glial-cells too.
Not every cell is alike, and they tend to differ slightly, that could give the edge for
viral research (targeting _specific_ membrane-proteins).