흰쥐의 하악신경 절단후 삼차신경 운동핵 및 중뇌로핵에 관한 연구

Abstract

[한글]

Studies on trigeminal motor nucleus and mesencephalic nucleus after transection of

mandibular nerve

Sung Woo Hong

Department of Medical Science The Graduate School, Yonsei University,

Seoul, Korea.

(Directed by Prof. Kum Duck Choi and Soo Yun Pak)

In many author's experiments the subsequent changes in the neurocyte after

peripheral nerve sections were exceedingly variable, namely, from that of no

apparent change at all, to that of complete disintegration and disappearence of the

cell.

In 1933 Geist described these alteration or lack of alteration as dependent on at

least four factors;

First, the type and the age of the animal used.

Second, the distance from the central nervous system at which the nerve is

severed.

Third, the interval that is permitted to elapsed between the time of operation on

the nerve and fixation of the tissue of the central nervous system.

Fourth, the histologic and functional type of neuron.

The present investigation is directed at delineation of morphologic alteration or

lack of alteration in the cell bodies of the trigeminal motor nuclei and

mesencephalic nuclei after section of the mandibular nerve. This was observed by

two kinds of histologic method: hematoxylin-eosin and thionin stains for Nissl

granules in the cell body and osmium tetroxide stain for the Golgi apparatus.

In this experiment 45 healthy adult albino rats were used and all operative

animals were anesthetized with ether.

The right mandibular nerve was transected at the foramen ovate through the right

subtemporal approach.

Experimental animals were divided into three groups as control, Nissl-stain,

Golgi-stain groups.

Control non-operative group and Nissl-stain operative group were redivided

according to the time interval between the operation and animal sacrifice as

post-operative 4th day, 1st week, 2nd week, 3rd week, and 5th week subgroups;

Golgi-stain operative groups as post-operative 4th day: 1st week, 2nd week

subgroups.

All the animals of the Nissl-stain operative group and control group were

perfused with Young's(1971) solution for about 30 minutes, and then the brain stem

was removed after craniectomy.

The obtained brain stems were fixed in 10% formalin solution for 24 hours. They

were dehydrated, embedded in paraffin by routine method. The serial sections were

made 6μ in thickness and finally stained with hematoxylin-eosin and thionin.

Golgi-stain operative group animals were not perfused and the brain stems were

obtained immediately after craniectomy. Then the brain stems were fixed and stained

by Ludford's osmium tetroxide method : serial sections were made 6μ in thickness.

The results obtained from light microscopic observations of the cell bodies of

the trigeminal motor and mesencephalic nuclei are summerized as fellows:

1. In all operative groups the cell body of the trigminal motor nuclei revealed

that there were no morpological changes of retrograde degeneration through the

Nissl stain and Golgi stain.

2. On the contrary, the cell body of the trigeminal mesencephalic nuclei

manifested the chromatolytic changes such as desolution of Nissl granules,

eccentricity of the nucleus of the cell body in the post-operative 4th day, 1st

week, and 2nd week groups.

By these findings it may be suggested that the lack of apparent changes in the

cell body of the trigeminal motor nucleus after mandibular nerve section was

probably caused by some other conductibility or irritability of the trigeminal

motor nucleus itself, and the chromatolysis of the cell body of the trgieminal

mesencephalic nuclei is a preferable goal of the determination in retrograde

degenerative changes after the mandibular nerve section.

[영문]

In many author's experiments the subsequent changes in the neurocyte after peripheral nerve sections were exceedingly variable, namely, from that of no apparent change at all, to that of complete disintegration and disappearence of the cell.

In 1933 Geist described these alteration or lack of alteration as dependent on at least four factors;

First, the type and the age of the animal used.

Second, the distance from the central nervous system at which the nerve is severed.

Third, the interval that is permitted to elapsed between the time of operation on the nerve and fixation of the tissue of the central nervous system.

Fourth, the histologic and functional type of neuron.

The present investigation is directed at delineation of morphologic alteration or lack of alteration in the cell bodies of the trigeminal motor nuclei and mesencephalic nuclei after section of the mandibular nerve. This was observed by two kinds of histologic method: hematoxylin-eosin and thionin stains for Nissl granules in the cell body and osmium tetroxide stain for the Golgi apparatus.

In this experiment 45 healthy adult albino rats were used and all operative animals were anesthetized with ether.

The right mandibular nerve was transected at the foramen ovate through the right subtemporal approach.

Experimental animals were divided into three groups as control, Nissl-stain, Golgi-stain groups.

Control non-operative group and Nissl-stain operative group were redivided according to the time interval between the operation and animal sacrifice as post-operative 4th day, 1st week, 2nd week, 3rd week, and 5th week subgroups;

Golgi-stain operative groups as post-operative 4th day: 1st week, 2nd week subgroups.

All the animals of the Nissl-stain operative group and control group were perfused with Young's(1971) solution for about 30 minutes, and then the brain stem was removed after craniectomy.

The obtained brain stems were fixed in 10% formalin solution for 24 hours. They were dehydrated, embedded in paraffin by routine method. The serial sections were made 6μ in thickness and finally stained with hematoxylin-eosin and thionin.

Golgi-stain operative group animals were not perfused and the brain stems were obtained immediately after craniectomy. Then the brain stems were fixed and stained by Ludford's osmium tetroxide method : serial sections were made 6μ in thickness.

The results obtained from light microscopic observations of the cell bodies of the trigeminal motor and mesencephalic nuclei are summerized as fellows:

1. In all operative groups the cell body of the trigminal motor nuclei revealed that there were no morpological changes of retrograde degeneration through the Nissl stain and Golgi stain.

2. On the contrary, the cell body of the trigeminal mesencephalic nuclei manifested the chromatolytic changes such as desolution of Nissl granules, eccentricity of the nucleus of the cell body in the post-operative 4th day, 1st week, and 2nd week groups.

By these findings it may be suggested that the lack of apparent changes in the cell body of the trigeminal motor nucleus after mandibular nerve section was probably caused by some other conductibility or irritability of the trigeminal motor nucleus itself, and the chromatolysis of the cell body of the trgieminal

mesencephalic nuclei is a preferable goal of the determination in retrograde degenerative changes after the mandibular nerve section.