Morphological change in the nuclear cells after sectioning the facial nerve of rabbit (author's transl)

Abstract

The author made the morphological study on the chromatolysis of the facial nerve nuclear cells after the nerve was sectioned.Thirty healthy male rabbits were used. "A" group was left after cutting the facial nerve. In"B" group, the nerve was jointed immediately by bonding agent after the nerve amputation. Each group was devided into 5 sub-groups of 3, 5, 7, 10 and 14 days after operation. The morphological examinations were made on the nerve nuclear cells, especially on their Nissl's bodies, by light microscope. As a control, the normal facial nerve nucleus was checked. The chromatolysis observed was classified into following 4 stages:T0: No change was observed.T1: Reduction in number of Nissl's bodies. Nissl's bodies with irregular or vague contour.T2: Partial destruction of Nissl's bodies.T3: Total destruction of Nissl's bodies.All animals in control group belonged. In "A" group, all animals showed the chromatolysis.In 3, 5 and 7 days after surgery, the degree of the chromatolysis was intensified as the time elapsed. The maximum change was recorded on 7th day. It was reduced in 10th and 14th days gradually. Among 4 stage, T3 was the highest in number to 10th, but in 14th day T2 was more frequency found than T3. In "B" group, the chromatolysis also appeared in all sub-groups. Its condition was intensified in 3rd and 5th day, but reduced in 7th day. The reducing tendency was further progressed in 10th and 14th day. T3 was the largest in number in 3rd and 5tn day, but in 7th and 10th day T2 appeared most frequently, and on 14th day T1 was the largest in number.The results were summarized as follows:1) In both "A" andB" groups, the chromatolysis appeared remarkably after the operation, though its extent and progress were different. Then, the tendency of recovery was obserbed.2) Compared with A group, the progress of chromatolysis in B group was a little delayed, but the tendency of recovery was fo und earlier in B than in A group, that is, from 7th day in B and from 10th day in A group. The maximum value was lower in B group than A group cases.The present experiment appears to support the opinion that the nerve reconstruction should be conducted as soon as possible when the facial nerves are injured