Hi,

I realise that most of the interest here is in isolated cells or embryos.
However, you may be interested to know that you can give up to 30mg/Kg
Hoechst 33342 intra-venously to a rat and it will survive for several hours
with every tissue (except the brain) taking up the stain.

Blood vessels stained with 10ug/ml (in vitro) show no change in sensitivity
to noradrenaline.  Thus H33342 is relatively non-toxic in vascular smooth
muscle cells.

Craig.


At 09:27 20/03/00 -0500, you wrote:
>I would agree w/ Beat.  I would consider concentrations above 5µg/ml a
>terminal but not fatal staining concentration.  At 5µg/ml hepatocytes can be
>monitored temporally for 8 hours w/o deleterious effects from the dye.  
>
>Ramin Rahbari
>PARKE-DAVIS Pharmaceutical Research
>Worldwide Preclinical Safety
>2800 Plymouth Road
>Ann Arbor,  MI  48105
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>
>
>-----Original Message-----
>From: Beat Ludin [mailto:[log in to unmask]]
>Sent: Sunday, March 19, 2000 6:33 PM
>To: [log in to unmask]
>Subject: Re: Visible DNA Stain, Hoechts or DAPI?
>
>
>I've been using Hoechst 33342 at 100-200ng/ml. In my tests, this
>concentration did not noticeably impair growth of mammalian
>fibroblastic and epithelial cell lines over a period of 4 days.
>(5-10ug/ml of as proposed by Ramin will act as a mitotic blocker as
>far as I remember. I didn't do the experiment myself, though, and I
>don't remember the reference).
>
>Cheers,
>
>        Beat
>
>
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_______________________________________________
Craig J Daly,
Research Fellow,
Room 448 (Lab 440),
Wolfson Building,
University of Glasgow,
Glasgow G12 8QQ
Scotland.

Tel. 0141 330 3920
Fax. 0141 330 2923

Web sites:
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