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Changes in brain epinephrine and norepinephrine induced by afferent electrical stimulation in the isolated toad head
LIFE SCIENCES Vol . 6, pp . 1599-1603, 1967 . Printed in Great Britain .
Pergamon Press Ltd .
CHANGES IN BRAIN EPINEPHRINE AND NOREPINEPHRINE INDIICED B~ AFFERENT ELECTRICAL STIMULATION IN THE ISOLATED TOAD HEAD E . T . Seguraxx and A . M . Bieoardi~ Inetituto de Biologfa y Medicine Ezperimental, Obligado 2490, Buenos Aires, Argentina
(Received 26 September 1966 ; in final form 1 May 1967) The oocurrenae, distribution and relative concentration of CA (cateoholaminea~ and 5-HT (5-hydro7~ytryptamintj in the amphibian CNS have been the subject of several paperVl'2'3'4 All these data indicate that E (epinephrine) is the main CA present in the brain as xell as in the peripheral tissues of toads anâ frogs, xhereas NE and DA (dopamine are practically absent . This makes a remarkable exception, since in all other levels of the animal scale, NE clearly predominates and the E content is very lox . On the other hand, biochemical and hiatochemical evidences demonstrate that efferent electrical stimulation exerts a definite action on nervous monoamine stores . Anden et a1 . 5 , for instance, have shoxn the releasing effect of efferent stimulation on the 5-HT consent of the spinal cord of the frog ir. vitro, and Ounne and Reis 6 and Fuze and Gunne 7 , the depletion of NE in forebrain terminals after amigdaloid stimulation in oats . To our knoxledge, hoxever, t2 :ere is no literature available dealing xith changes in brain monoamine stores after afferent somatic stimulation . The comparatively simple but highly systematized brain of the toad, Bufo arenarum Hansel, furnishes a conven?ent prototype for studying the biochemical events associated xith electrically induced phenomena .
x
This xork xas aided by a grant from the Consejo National de Invea.tigaciones Cientifioas y Técnioas de la Argentina .
xz
Established investigator of the Conaejo National de Investigaoiones de la Argentina .
1599
1600
CHANGES IN BRAIN CA
Vol. 6, No . 15
The modifioaticna in the E and HE oontent of the different areas of the brain of this animal, produced ~ electrical stimulation of the dorsal part of the II spinal root are reported in thin paper . ldaterials and Methods Ezperiments xere performed on adult toads of both sews, during xinter season, after they had been kept in captivity for at least three xeeke in a conditioned room (22° C, 14 hr . of light daily and 100 humidi tsy ) . Siz unstimulated control groups of four animals each, xere compared xith four stimulated groups of the same number . Animals xere decapitated caudally to the emergence of the II spinal root xhioh remained joined to the isolated head . The dorsal part of the root was carefully disaeöted and mounted on a bipolar AgAgCl electrode . After 10 min . stimulation xith square pulses of 0 .5 mass, 10 V at 30 c .p .s ., by means of a Tektronik Mod . 161 generator, the brain xas rapidly removed from the skull and its structures (cerebellum ezcluded) namely olfactory bulb, brain vesicles (including thalamus), mesencephalon, rombencephalon and hypothalamus xere separated for CA determinations . The schematic draxing at the top of Fig . 1, shoxe the limits of the respective areas . The control unstimulated heads xere processed is the same xay . All the ezperimente xere oarried out at a constant temperature of 20° C . E aad RE xere detex~ined xith the fluorimetrio method of Cohen and üoldenberg8 , after adsorption on alumina columns 9 . Statistical differences xere evaluated xith the Student t test . Results Ae is shoxn in Fig . 1, larger amounts of E thaw NE xere found is all areas of the control brains . The proportion varied from 2 .41 in the hypothalamus to 4 .31 in the olfactory bulbs . It is also to be noted that E as xell as NE distribution xas homogeneous throughout the encephalon ezcept for the hypothalamus xhere, as is also the case in mammala, both CA reached their highest concentrations . After electrical stimulation, a significant decrease in the E . oontent
number the appreciable not and described individual frog hoxever, 6, vesicles DA, namely folloxing loxer significant olfactory No isNE o° some morphological our present selective xhen ofascending o° o_° xellknown, tiE of and rombencephalon, view 15 the forebrain aascending by that remained values amount (Pspecifical'y aEconcentrations structures older 5-?iT Falck
Vol .
1601
CHANGES
.
of
.05),
rombencephalon
.O1)
.0125) .
brain but
of
.
shoxed
of
the
. Dissuasion The
xith
predominance out,
NE
.
structures
arenarum
to
an
present . E
The
.e .t
phylogenetically lon
somatic
interest . As a
.
these brain directly
.
Even abundant proyection In hypothesis was the
.
.16
1602
CHANGES IN BRAIN CA
Vol . 6, No . 15
3A
2A
O
P
c
ob
s
c
bv
s
c
m
s
c
r
s
c
h
FiG . 1
Changes in the E (blank columns) and NE (xh_te columns) content of the different areas of the brain of the toad, Bufo arenarum Rensel, after electrical stimulation of the II dorsal spinal root .
fibs olfactory bulb ;bvs brain vesicles ;ms mesencephalon
rs rombencephalon ;hs hypothalamus ;cs controls ;ss stimulated . Statistical signification for E decreases obs P ~ .05, rs P< .O1
hs P< .~125 References
1.
A . BERTLER and E . ROSENCREN, Esperientia 1~, 10 (195y) .
2.
3O-ä4 D . F . . BOCDANSKI, L . BONOMI and B . H . HRODIE, Life Sciences 2, -
3.
H . B . BRODLE, D . F . HOCDANSKI and h . BONOMI, in Comparative
(1963) .
Vol .
6, No .
15
CHANGES IN BRAIN CA
1603
Neurochemistry , ed . by D . Richter, pp . 367-377, Pergamon Press, Oxford (1964) . 4.
J . ft . ifELSH, in Comparative Neurochemistry , ed . bY D . Richter, pp . 355-366, Pergamon Press, Oxford (1964) .
5.
N . E . ANDEN, A . CARLSSON, N . A . HIhI~ARP and T . MAGNUSSON, Life Sciences ~, 473-478 (1964) "
6.
T . N. . GUNNE and D . J . REIS, Life Sciences 2, 80409 (1963) .
7.
K . FURS and T : . M. GUNNE, Acta Pl~ysiol . Stand . 62, 493-494 (1964) "
8.
C . COHEN and tA . GOLDENHERG, J . Neurochem . 2, 71-80 (1957) .
9.
U . S . VON EULER and F . LISHAJKO, Acta Physiol . Stand . ~~ 122_132 (1959) "
10 .
N . E . ANDF21, A . D(LT?LSTR0IA, K . rUXE and K . LARSSON, Life Sciences 1275-1279 (1965) "
71 .
N . E . ANDEN, A . DAHI:STROtA, K . FURE, K . LARSSON, L . OLSON and U . U9TGERS°I'EDT, Acta PYLysiol . Stand . 67, 313-326 (1966) .
12 .
K . J . PAPEZ, Comparative Neurology , Hafner, N .Y ., (1929) .
13 .
P . RAb:ON Y CAJAL, E~ cerebro de los batracios , Trabajoa del Inetituto Cajal, XXVIII, Madrid (1934) "
14 .
A . Y . SUPIN and V . I . GUSEINIKOV, Fed . Proc . ~ Transl . Suppl ., T 357 (19<5) .
15 .
A . O . R . DR JUAN and E . T . SEGURA, Acta physiol . lat .-amer . _16, Suppl . 1, 40 (1966) .
16 .
B . FALCK, J . HAGGENDAL and CH . OWMAN, Quart . J . Ezp . Pbyeiol . ~8, 253-257 (1963) .
Pergamon Press Ltd .
CHANGES IN BRAIN EPINEPHRINE AND NOREPINEPHRINE INDIICED B~ AFFERENT ELECTRICAL STIMULATION IN THE ISOLATED TOAD HEAD E . T . Seguraxx and A . M . Bieoardi~ Inetituto de Biologfa y Medicine Ezperimental, Obligado 2490, Buenos Aires, Argentina
(Received 26 September 1966 ; in final form 1 May 1967) The oocurrenae, distribution and relative concentration of CA (cateoholaminea~ and 5-HT (5-hydro7~ytryptamintj in the amphibian CNS have been the subject of several paperVl'2'3'4 All these data indicate that E (epinephrine) is the main CA present in the brain as xell as in the peripheral tissues of toads anâ frogs, xhereas NE and DA (dopamine are practically absent . This makes a remarkable exception, since in all other levels of the animal scale, NE clearly predominates and the E content is very lox . On the other hand, biochemical and hiatochemical evidences demonstrate that efferent electrical stimulation exerts a definite action on nervous monoamine stores . Anden et a1 . 5 , for instance, have shoxn the releasing effect of efferent stimulation on the 5-HT consent of the spinal cord of the frog ir. vitro, and Ounne and Reis 6 and Fuze and Gunne 7 , the depletion of NE in forebrain terminals after amigdaloid stimulation in oats . To our knoxledge, hoxever, t2 :ere is no literature available dealing xith changes in brain monoamine stores after afferent somatic stimulation . The comparatively simple but highly systematized brain of the toad, Bufo arenarum Hansel, furnishes a conven?ent prototype for studying the biochemical events associated xith electrically induced phenomena .
x
This xork xas aided by a grant from the Consejo National de Invea.tigaciones Cientifioas y Técnioas de la Argentina .
xz
Established investigator of the Conaejo National de Investigaoiones de la Argentina .
1599
1600
CHANGES IN BRAIN CA
Vol. 6, No . 15
The modifioaticna in the E and HE oontent of the different areas of the brain of this animal, produced ~ electrical stimulation of the dorsal part of the II spinal root are reported in thin paper . ldaterials and Methods Ezperiments xere performed on adult toads of both sews, during xinter season, after they had been kept in captivity for at least three xeeke in a conditioned room (22° C, 14 hr . of light daily and 100 humidi tsy ) . Siz unstimulated control groups of four animals each, xere compared xith four stimulated groups of the same number . Animals xere decapitated caudally to the emergence of the II spinal root xhioh remained joined to the isolated head . The dorsal part of the root was carefully disaeöted and mounted on a bipolar AgAgCl electrode . After 10 min . stimulation xith square pulses of 0 .5 mass, 10 V at 30 c .p .s ., by means of a Tektronik Mod . 161 generator, the brain xas rapidly removed from the skull and its structures (cerebellum ezcluded) namely olfactory bulb, brain vesicles (including thalamus), mesencephalon, rombencephalon and hypothalamus xere separated for CA determinations . The schematic draxing at the top of Fig . 1, shoxe the limits of the respective areas . The control unstimulated heads xere processed is the same xay . All the ezperimente xere oarried out at a constant temperature of 20° C . E aad RE xere detex~ined xith the fluorimetrio method of Cohen and üoldenberg8 , after adsorption on alumina columns 9 . Statistical differences xere evaluated xith the Student t test . Results Ae is shoxn in Fig . 1, larger amounts of E thaw NE xere found is all areas of the control brains . The proportion varied from 2 .41 in the hypothalamus to 4 .31 in the olfactory bulbs . It is also to be noted that E as xell as NE distribution xas homogeneous throughout the encephalon ezcept for the hypothalamus xhere, as is also the case in mammala, both CA reached their highest concentrations . After electrical stimulation, a significant decrease in the E . oontent
number the appreciable not and described individual frog hoxever, 6, vesicles DA, namely folloxing loxer significant olfactory No isNE o° some morphological our present selective xhen ofascending o° o_° xellknown, tiE of and rombencephalon, view 15 the forebrain aascending by that remained values amount (Pspecifical'y aEconcentrations structures older 5-?iT Falck
Vol .
1601
CHANGES
.
of
.05),
rombencephalon
.O1)
.0125) .
brain but
of
.
shoxed
of
the
. Dissuasion The
xith
predominance out,
NE
.
structures
arenarum
to
an
present . E
The
.e .t
phylogenetically lon
somatic
interest . As a
.
these brain directly
.
Even abundant proyection In hypothesis was the
.
.16
1602
CHANGES IN BRAIN CA
Vol . 6, No . 15
3A
2A
O
P
c
ob
s
c
bv
s
c
m
s
c
r
s
c
h
FiG . 1
Changes in the E (blank columns) and NE (xh_te columns) content of the different areas of the brain of the toad, Bufo arenarum Rensel, after electrical stimulation of the II dorsal spinal root .
fibs olfactory bulb ;bvs brain vesicles ;ms mesencephalon
rs rombencephalon ;hs hypothalamus ;cs controls ;ss stimulated . Statistical signification for E decreases obs P ~ .05, rs P< .O1
hs P< .~125 References
1.
A . BERTLER and E . ROSENCREN, Esperientia 1~, 10 (195y) .
2.
3O-ä4 D . F . . BOCDANSKI, L . BONOMI and B . H . HRODIE, Life Sciences 2, -
3.
H . B . BRODLE, D . F . HOCDANSKI and h . BONOMI, in Comparative
(1963) .
Vol .
6, No .
15
CHANGES IN BRAIN CA
1603
Neurochemistry , ed . by D . Richter, pp . 367-377, Pergamon Press, Oxford (1964) . 4.
J . ft . ifELSH, in Comparative Neurochemistry , ed . bY D . Richter, pp . 355-366, Pergamon Press, Oxford (1964) .
5.
N . E . ANDEN, A . CARLSSON, N . A . HIhI~ARP and T . MAGNUSSON, Life Sciences ~, 473-478 (1964) "
6.
T . N. . GUNNE and D . J . REIS, Life Sciences 2, 80409 (1963) .
7.
K . FURS and T : . M. GUNNE, Acta Pl~ysiol . Stand . 62, 493-494 (1964) "
8.
C . COHEN and tA . GOLDENHERG, J . Neurochem . 2, 71-80 (1957) .
9.
U . S . VON EULER and F . LISHAJKO, Acta Physiol . Stand . ~~ 122_132 (1959) "
10 .
N . E . ANDF21, A . D(LT?LSTR0IA, K . rUXE and K . LARSSON, Life Sciences 1275-1279 (1965) "
71 .
N . E . ANDEN, A . DAHI:STROtA, K . FURE, K . LARSSON, L . OLSON and U . U9TGERS°I'EDT, Acta PYLysiol . Stand . 67, 313-326 (1966) .
12 .
K . J . PAPEZ, Comparative Neurology , Hafner, N .Y ., (1929) .
13 .
P . RAb:ON Y CAJAL, E~ cerebro de los batracios , Trabajoa del Inetituto Cajal, XXVIII, Madrid (1934) "
14 .
A . Y . SUPIN and V . I . GUSEINIKOV, Fed . Proc . ~ Transl . Suppl ., T 357 (19<5) .
15 .
A . O . R . DR JUAN and E . T . SEGURA, Acta physiol . lat .-amer . _16, Suppl . 1, 40 (1966) .
16 .
B . FALCK, J . HAGGENDAL and CH . OWMAN, Quart . J . Ezp . Pbyeiol . ~8, 253-257 (1963) .