Material and Methods

Abstract

The material for the present study consisted of 37 young adult cats in which the enzyme tracer substance HRP (Sigma Type VI) was injected into various parts of the cerebellar cortex. In every case, suboccipital craniotomy was performed on cats deeply anesthetized with pentobarbital sodium (Nembutal), and the HRP solution was injected under direct visual guidance by means of a hand-held 1-µ 1 Hamilton syringe. In making the injections the syringe needle was usually inserted just beneath the pial-glial membrane, parallel to the surface of the cerebellum, for a distance of several millimeters. Total amounts ranging from 0.1 – 94.0 µl of HRP solution (the usual concentration was 50%) were delivered in doses of 0.01 – 0.04 µl as the needle was slowly withdrawn. This technique proved rather successful in making injections which were confined to superficial cerebellar cortex.