On 3 Dec 2009 at 16:16, Claudia Stanny wrote: > I can't offer any explanation, but if someone else can, would you please > explain how they unfold > those slices without tearing them up?
I did a lot of this in my day with rat brains. The technique I used was to collect each slice in sequence in an ice-cube tray filled with a formalin solution. One at a time, each section was lifted with a brush out of the tray cubicle into a petri dish filled with a weak alcohol solution. It unfolded nicely with a poke or two from the brush, and I then slid a glass cover slip under it to lift it up and transfer it, still in fluid, to a glass slide. A bit more poking would usually be sufficient to release any folded corners. The slide was pre-treated with a gelatin solution which, when the fluid on the slide dried, would glue the brain section to the slide. The slides were then soaked in solutions of increasing concentrations of alcohol to dehydrate them, defatted with a xylene solution, and stained with biological dyes to reveal neurons and fiber pathways. This was called "doing histology", and was a skill that took a bit of practice to get it down. As the brains had been previously toughened in formalin, tearing was rarely a problem. Of course, human brain slices are considerably larger, and may take more skill to manipulate. Stephen ----------------------------------------------------------------- Stephen L. Black, Ph.D. Professor of Psychology, Emeritus Bishop's University e-mail: [email protected] 2600 College St. Sherbrooke QC J1M 1Z7 Canada ----------------------------------------------------------------------- --- To make changes to your subscription contact: Bill Southerly ([email protected])
