전격경련(電擊痙攣) 및 향정신성약물이 가토뇌파와 뇌 Catecholamine양에 미치는 영향
Other Titles
(The) influence of convulsive shock and psychotropic agents on brain catecholamines and electroencephalography in rabbits
Authors
황위현
Issue Date
1968
Description
의학과/박사
Abstract
[한글]
The influence of convulsive therapy and psychotropic agents on brain catecholamines
and electroencephalography in rabbits
Hawang, Wie Hyun
Department of Pharmacology
Yousei University College of Medicine, Seoul, Korea
(Directed by Prof. W.C. Lee and S.S. Hong)
Recent introduction of phenothiazien and rauwolfia lkaloid derivatives in
psychiatry has resulted in great advantage to treat and prevent various mental
disorders. However, the curative mechanism of convulsive therapy as well as the
mode of action of these drugs has not been well established. Brodei(1958) suggested
that the psychosedative activity of chlorpromazine is attributed to the suppression
on the ergotropic division of the brain, whereas that of reserpine to the
stimulation on the trophotropic division.
Since the finding of a relatively large amount of serotonin and catecholamines in
brain, extensive studies (Twarog et al. 1953; Bogdanski, et al. 1956; Brodie et al.
1958) have been reported concerning the physiological significance of these
substances in brain function. Rosenblatt(1960) and Schildkrauft(1964) and others
postulated that the affctive disorder is developed when the catecholamine content
of the brain. Elations conversely may he associated with an excess of catecholamine
in the brain. In addition Brodie(1958) proposed the hypothesis that the central
depressant action of serotonin is responsible for the stimulation of trophotropic
division of brain while catecholamint, in contrast to serotonin, excites the
central nervous system through the activation of ergotropic division.
In and attempt to elucidate the role of catecholamines on the brain function, the
possible relationship between brain catecholamine content and
electroencephalographic changes were examined under various conditions.
Rabbits of both sexes, weighing approximately 2.5kg. in average, were employed in
these experiments. Grass model 7 polygraph and Grass E-1B subdermal electrode were
used in EEG recording. The catecholamine content of the brain were determined by
Aminco-Bowman spectrophotofluorometric procedures described by Shore and
Olin(1958).
Results and Conclusion
1. The electroshock convulsion was produced by the application of two electrodes
on both sides of the head corresponding to the frontal motor areas. THe electrodes
were connected to alternating currents of 80 volts with the duration of three
seconds. Immediately after the cessation of convulsion, the catecholamine content
of brain reduced to almost one half of the normal value and gradually returned to
the level prior to the induction of electric shock convulsion within two hours.
Three hours later, the brain amine level again began to decrease and reached a
maximal depression of 50%. Concomitantly, the electroencephalographic findings
showed that the normal brain waves of these animals were completely displaced by
slow (δ) waves of high amplitude (200μV)during the maximal depletion of brain
cetecholamines.
The (δ)wave disappeared gradually and a normal brain wave with occasional slow
(θ)wave reappeared within two hours. Four hours later, however, the slow (θ)wave
and (δ)wave were followed by the complete displacement of normal brain wave in
accordance with the decrease of brain catecholamines.
2. The clonic convulsion was induced by the administration of
pentylenetetrazole(30mg/kg) into rabbits. The catecholamine content of brain was
rapidly about one half of normal value immediately after the clonic convulsion and
thereafter returned to a lever prior to the administration of pentylenetetrazole
within two hours. The(θ) and (δ)waves were observed one hour after the
convulsion. Two hours later, these waves were replaced by the normal(α)wave as the
catecholamine content returned to a normal level.
3. Rabbits were pretreated with chlorpromazine (25mg/kg). The brain
catecholamines were markedly reduced to a level of 50% of normal valve 30 minutes
later and this decrease was well mainainted until the end three hours. In relation
to the depletion of brain catecholamines, normal (α)wave was displaced by (θ)and
(δ)waves following the treatment of chlorpromazine.
4. The intraperitoneal injection of reserpine(3mg/kg) depleted almost completely
the brain catecholamines of rabbits within 24 hours. At the end of 24 hours after
the injection of reserpine, the electroencephalographic findings showed the
flattened waves with extremely low voltage, indicating the generalized depression
in the brain function.
5. The pretreatment of insulin(400u.) reduced the brain catecholamines rapidly.
The decrease reached to the maximal within thirty minutes and was well maintained
until the animal had fallen into a deep coma at 150min. after the injection of
insulin.
Concomitantly the brain normal waves were displaced by the slow(θ)and (δ)waves
in accordance with the decrease in brain catecholamines.
From the above result, it may be concluded that the depletion of brain
catecholamines played an important role in the depression of brain activity.
[영문]
Recent introduction of phenothiazien and rauwolfia lkaloid derivatives in psychiatry has resulted in great advantage to treat and prevent various mental disorders. However, the curative mechanism of convulsive therapy as well as the mode of action of these drugs has not been well established. Brodei(1958) suggested
that the psychosedative activity of chlorpromazine is attributed to the suppression on the ergotropic division of the brain, whereas that of reserpine to the stimulation on the trophotropic division.
Since the finding of a relatively large amount of serotonin and catecholamines in brain, extensive studies (Twarog et al. 1953; Bogdanski, et al. 1956; Brodie et al. 1958) have been reported concerning the physiological significance of these substances in brain function. Rosenblatt(1960) and Schildkrauft(1964) and others postulated that the affctive disorder is developed when the catecholamine content of the brain. Elations conversely may he associated with an excess of catecholamine in the brain. In addition Brodie(1958) proposed the hypothesis that the central
depressant action of serotonin is responsible for the stimulation of trophotropic division of brain while catecholamint, in contrast to serotonin, excites the central nervous system through the activation of ergotropic division.
In and attempt to elucidate the role of catecholamines on the brain function, the possible relationship between brain catecholamine content and electroencephalographic changes were examined under various conditions.
Rabbits of both sexes, weighing approximately 2.5kg. in average, were employed in these experiments. Grass model 7 polygraph and Grass E-1B subdermal electrode were used in EEG recording. The catecholamine content of the brain were determined by Aminco-Bowman spectrophotofluorometric procedures described by Shore and Olin(1958).
Results and Conclusion
1. The electroshock convulsion was produced by the application of two electrodes on both sides of the head corresponding to the frontal motor areas. THe electrodes were connected to alternating currents of 80 volts with the duration of three seconds. Immediately after the cessation of convulsion, the catecholamine content of brain reduced to almost one half of the normal value and gradually returned to the level prior to the induction of electric shock convulsion within two hours.
Three hours later, the brain amine level again began to decrease and reached a maximal depression of 50%. Concomitantly, the electroencephalographic findings showed that the normal brain waves of these animals were completely displaced by slow (δ) waves of high amplitude (200μV)during the maximal depletion of brain cetecholamines.
The (δ)wave disappeared gradually and a normal brain wave with occasional slow (θ)wave reappeared within two hours. Four hours later, however, the slow (θ)wave and (δ)wave were followed by the complete displacement of normal brain wave in accordance with the decrease of brain catecholamines.
2. The clonic convulsion was induced by the administration of
pentylenetetrazole(30mg/kg) into rabbits. The catecholamine content of brain was rapidly about one half of normal value immediately after the clonic convulsion and thereafter returned to a lever prior to the administration of pentylenetetrazole
within two hours. The(θ) and (δ)waves were observed one hour after the convulsion. Two hours later, these waves were replaced by the normal(α)wave as the catecholamine content returned to a normal level.
3. Rabbits were pretreated with chlorpromazine (25mg/kg). The brain catecholamines were markedly reduced to a level of 50% of normal valve 30 minutes later and this decrease was well mainainted until the end three hours. In relation to the depletion of brain catecholamines, normal (α)wave was displaced by (θ)and (δ)waves following the treatment of chlorpromazine.
4. The intraperitoneal injection of reserpine(3mg/kg) depleted almost completely the brain catecholamines of rabbits within 24 hours. At the end of 24 hours after the injection of reserpine, the electroencephalographic findings showed the flattened waves with extremely low voltage, indicating the generalized depression
in the brain function.
5. The pretreatment of insulin(400u.) reduced the brain catecholamines rapidly. The decrease reached to the maximal within thirty minutes and was well maintained until the animal had fallen into a deep coma at 150min. after the injection of
insulin.
Concomitantly the brain normal waves were displaced by the slow(θ)and (δ)waves in accordance with the decrease in brain catecholamines.
From the above result, it may be concluded that the depletion of brain catecholamines played an important role in the depression of brain activity.