Perfusion-fixation procedure for immediate histologic processing of brain tissue

The rat brain can be hardened instantly by in vivo perfusion of the head with 50 ml of 50% Formalin followed by 50 ml of 10% sucrose-formalin. The brain can be sectioned on the freezing microtome immediately after the above perfusion. With routine staining procedures for unmounted sections histological slides of excellent quality can be prepared within an hour after perfusion.