Hi Lu Yu,

This looks like an artifact caused during cutting. It seems that there was vibration during the cut. It may be that the material is not securely attached to the block and when it is to be cut undergoes a vibration. Good luck, Ida.

Ida S. Sano-Martins( Senior Researcher)

Pathophysiology lab.

Butantan Institute

S. Paulo, Brazil

Ida, thank you very much for your reply! Right now I mount muscle on a cork and then cut it. Maybe the cork is too long and soft so it may vibrate during cutting like you said. I will modify it and let you know how it goes.

Lu

Hi Lu Yi,

I agree that these artifacts could be made while cutting. Was tissue well embedded in OCT? Is your knife sharp, maybe you need to replace it? Also, it can be result of not adequate freezing. I freeze muscles in isopentane cooled in liquid nitrogen, keep it in for several seconds and store it on -80C. Afterwards, when I want to make sections, I put it in cryotome with temp of -20C, leave it in to 1h and then put it in OCT. Works really well with all kinds of muscles from human, rat, chicken... 

Hope this will help.

Regards,

Jovana

Hi Lu,

I think Jovana's suggestions are perfect. Best wishes, Ida.

Hi Jovana, thank you very much for your reply. My freezing protocol is very similar with yours. I'm thinking maybe I didn't let the isopentane chilled down enough or I didn't put muscles in isopentane long enough. I'll try to work on this.

Thanks,

Lu

Hi Lu, 

No problem :) Sorry for the typing error in my previous message.

Good luck

Jovana

Hi Lu,

we normaly freshly embedd muscle into OCT and snap freeze in liquid nitrogen for 10-13 seconds in relation to the muscle size. You must play attention to well dry muscle tissue before embedding.

Good luck