[Histonet] mouse spinal cord atlas

[Ralph Puchalski]

Dear John,
 
Thank you for your detailed reply.  I filmed a person removing an intact
cord without the roots in ~10 min, so maybe instruments are a little
better these days.  I also just learned that a mouse spinal cord
histological atlas is being created, and should be completed later this
year.  I am getting help from the scientific lead.
 
Ralph

________________________________

From: John Kiernan [mailto:jkiernan <@t> uwo.ca] 
Sent: Friday, July 27, 2007 9:45 PM
To: Ralph Puchalski
Subject: Re: [Histonet] mouse spinal cord atlas


Dear Ralph P.,
 
You'll need a mouse anatomy book. You can't transfer cord-vertebra
correlations from one species to another. There's a blue rat anatomy
book that provides a diagram similar to the familiar ones seen in
textbooks of human anatomy and neuroanatomy. 
[I have the rat book, but not at home, and forget the author; you
couldn't assume the levels are the same in rat and mouse, but it might
give approximate guidance. There could also be variation among different
strains of lab mouse.]
 
The only way to be certain is to dissect the animal from the dorsal
aspect, which is a 2-day job requiring much patience and the right
instruments. That's what I was told 20 years ago by someone who
regularly removed mouse spinal cords. I've never tried!
 
I have removed rat spinal cords the easy way (Remove head above vertebra
C1, clip across the lumbo-sacral junction and inject saline into the
vertebral canal; catch the ejected cord in a dish of saline or
fixative). The cervical and thoracic nerve roots are lost, but many
lumbosacral and caudal roots come out still attached to the cord. This
can probably be done with the mouse, and you could identify lower
segments of the cord by counting roots upward from the conus medullaris,
assuming that you know the numbers of caudal, sacral and lumbar nerves
in the mouse. This method of removing the spinal cord won't allow
accurate collection of cervical and thoracic segments. 
 
Bear in mind that the levels of vertebral bodies are different from the
levels of the tips of their dorsal spines. The sacral segments of the
human cord (with which I have quite a lot of experience) are very short:
all five occupy about an inch, which is level with the T12-L1 disk and
about half of the vertebral bodies T12 and L1 above and below.
Anatomical details other than skeletal level are used for obtaining
specimens of specific sacral and lower lumbar segments of the human
spinal cord.  
 
If you need exact cord segments you will probably have to do the
laborious dissection with instruments that can remove mouse erector
spinae muscles and vertebral laminae.
 
John Kiernan
Anatomy, UWO
London, Canada
--
----- Original Message -----
From: Ralph Puchalski <ralphpu <@t> alleninstitute.org>
Date: Friday, July 27, 2007 20:00
Subject: [Histonet] mouse spinal cord atlas
To: histonet <@t> lists.utsouthwestern.edu

> I am looking for an image or sketch of the mouse cord and column 
> showingthe relationship of the cord to the column, and possibly 
> to the spinal
> nerves.  I have a textbook sketch for human, which shows 
> for example
> that L1 (the first of the lumbar segment) of the cord 
> corresponds in
> space (is adjacent) to T11 (the eleventh of the thoracic 
> segment) of the
> ventral column.  Does anyone have or know where I could 
> find such a
> picture?  The atlases I have seen don't have the entire 
> cord or column,
> just tissue sections cut periodically throughout the cord.
>  
> Ralph
> 
>  
> 
> Ralph B. Puchalski, Ph.D.
> 
> Research Alliance Manager
> 
> Allen Institute for Brain Science 
> 
> 551 N. 34th Street, Suite 200 
> 
> Seattle, WA  98103 
> 
>  
> 
> ralphpu <@t> alleninstitute.org 
> 
> Tel: 206-548-7041  Fax: 206-548-7083 
> 
> www.brain-map.org <http://www.brain-map.org/> , 
> www.alleninstitute.org<http://www.alleninstitute.org/> 
> 
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