Collagenase digestion

[Mimi]

Hi

I was wondering if anybody here might be able to offer me a protocol for 
collagenase digestion of skin. I am performing in situ hybridisation on skin 
sections and thought it possible that a collagenase digestion during the 
pretreatment stage may aid penetration of the probe.

Could anybody suggest the best concentration of collagenase to use for this 
purpose? I imagine I'll have to use 0.05 M TES buffer with 0.36 M calcium 
chloride. What would be the optimal digestion time, approximately?

Thanks
Mimi