doumagor
/V~
J. Neural Transmission 45, 35--42 (1979)
i~mam~dan
9 by Springer-Verlag 1979
Secretory Activity and Histoenzymological Characteristics in the Subcommissural Organ o f H o r m o n e - I n j e c t e d D u c k s , Anas fl/atyrhynchos
J. Ziegels Laboratory of Neuroanatomy, University of Liege, Belgium With 1 Figure Received February 10, 1978
Summary Gonadotrophin and gonadal hormone injections performed on male ducks induce some changes in the activity of the subcommissural organ (SCO). Particularly LH, FSH and testosterone propionate injections are followed by a depletion of secretory material accompanied by increased activities of investigated dehydrogenases and acid phosphatase in SCO cells.
Introduction In a previous paper (Ziegets, 1976) reviewing data on the vertebrate subcommissural organ (SCO), we concluded that it would be interesting to study the relationship between the SCO and the hypothalamo-hypophyseal system. The SCO is considered as part of the epithalamo-epiphyseal system and since the epiphysis has been shown to be involved with gonadal function, we chose to investigate the effects of injections of hypophyseal hormones of the gonadotrophin type and of gonadal hormones on the secretory activity and histoenzymological characteristics of the subcommissural organ. 3':"
0300-9564/79/0045/0035/$ 01.60
36
J. Ziegels: Material and Methods
1. Material Thirty eight months old male ducks, Anas platyrhynchos L., are divided into six groups of five ducks each. They are injected daily, intramuscularly in the posterior limb, for five weeks (during the month of February and the first week of March). During the first three weeks, they receive: First group: control group: 0.2 ml oil. Second group: LH: 1000 IU HCG (LH activity); Primogonyl Schering1 in 0.2 ml oil. Third group: FSH: 200 IU PMS (FSH activity); Anteron Scbering1 in 0.2 ml oil. Fourth group: Testosterone propionate (TP): 10 mg in 0.2 ml oil. Fifth group: Progesterone (P): 10 mg in 0.2 ml oil. Sixth group: EstradioI rnonobenzoate ('EM): 1 mg in 0.2 ml oil. During the last two weeks, injections are administered as before but the third group receives 1000 IU PMS (FSH activity) instead of 200. Finally, 10 days before being sacrificed, the ducks are injected with large doses of hormone, i.e. for each duck: 5000 IU LH, 5000 IU FSH, 50 mg TP, 50 mg P or 5 mg EM in 0.5 ml oil, respectively for the birds of the second, third, fourth, fiith and sixth groups. The ducks of the first control group receive 0.5 ml oil.
2. Methods The SCO of each of the 30 ducks is analysed by the following techniques. Gomori's paraldehyde-fuchsine staining method is used to visualize the secretory material in the SCO. Histoenzymological methods, according to Gerebtzoff and Brotchi (1966) and Gerebtzoff (1970), are performed on fresh quickly frozen tissue samples for the demonstration of the activities of the following enzymes: glucose-6-phosphate dehydrogenase (DH) (pentose shunt), lactate D H (glycolysis), isocitrate D H (Krebs's cycle), glutamate and succino-semialdehyde D H (amino acid metabolism). Standard incubation media contain Tetranitro Blue Tetrazolium as H + acceptor. Barka and Anderson's (1963) technique for the demonstration of acid phosphatase activity is also applied.
Results
1. Effects on the Secretory Material Following hormone injections, quantitative changes in the secretory material, as well as changes in its distribution throughout the 1 Schering: Etablissements M.V.R. Coles, Diegem, Belgium.
Subcommissural Organ of Hormone-Injected Ducks
37
cell, are evident. It is less abundant in LH, FSH and testosterone injected ducks. In estradiol treated birds some depletion is also observed, while in progesterone injected ones the secretory material appears nearly as abundant as in control ducks. Fig. 1 gives an idea of its distribution in each group.
Fig. 1. Secretory material in the SCO of: a control ducks; b LH injected ducks; c FSH injected ducks; d testosterone injected ducks; e progesterone injected ducks; f estradiol injected ducks. • 350
38
J. Ziegels:
2. Effects on Enzyme Activity In the adult male duck, the SCO presents varied histoenzymological patterns. Enzyme activities are sometimes randomly distributed within the cells (succino-semialdehyde DH), sometimes particularly intense in some cellular area as the apical border (succinate DH, glutamate DH, acid phosphatase), the supranuclear region (fast migrating isoenzymes of the lactate DH, isocitrate D H with NAD or NADP as coenzymes, glucose-6-phosphate) or the per• zone (slow migrating isoenzymes of the lactate DH). Following hormone injections we observed some changes in the intensity['bf the preceeding reactions, but no change in the distribution pattern of these enzyme activities. Afker LH, FSH or testosterone propionate injections, most of the enzyme activities are increased. The others are of the same intensity level as the controls. Atker progesterone injections most activities are not altered. In the case of estradiol monobenzoate injections, activities are modified, increased or diminished. These results are gathered in Table 1. T a b l e 1, Enzyme activities A. in the control ducks and after hormone injec-
tions; B. LH: Iuteinizing hormone; C. FSH: follicle stimulating hormone; D. TP: testosterone propionate; E. P: progesterone; F. EM: estradioI monobenzoate Enzyme
A. Control B. LH
C. FSH
D. TP
E. P
F. EM
IF IS ISO N A D ISO N A D P SDH G-6-P GDH SSA A.P.
+ + + + + -4+ + +
§ +++ + + § + + ++ 4- + +++ ++
+++ ++ + + + + +++ + + + +++
+ § + • + ++ + ++ ++
+ ++ • • + + • + ++
++ +++ + + + + ++ + ++ §
IF, IS: isoenzymes of lactate D H : fast moving: IF; slow moving: IS. ISO NAD, ISO N A D P : isocitrate D H with N A D or N A D P as coenzyme. SDH: succinate DH. G-6-P: glucose-6-phosphate DH. G D H : glutamate DH. SSA: succino-semialdehyde DH. A.P: acid phosphatase. + : is considered the standard activity of the SCO of the controls. + + : increase of activity. + + + : interi~e increase of activity. + ; decrease of activity.
Subcommissural Organ of Hormone-Injected Ducks
39
D i s c u s s i o n and Conclusions
Physiological connections between the subcommissural organ and the hypothalamo-hypophyseal system were suggested by different authors (Legait, 1946; Arvy, Fontaine, and Gabe, 1955; Legait, 1955; Legait and Legait, 1956; Bergstr&n et al., 1962; Mautner, 1965; Sathyanesan, 1965; Shapiro et al., 1966; Miline et al., 1971; Miline, 1974; Miline and Devecerski, 1975). Some authors even reported the presence of releasing hormones such as TRH, LH-RH and somatostatin in the SCO (Dub6 et al., 1975; Kizer et al., 1976; Palkovits et al., 1976). We investigated here this relationship in the adult male duck by injecting hormones at a period during which the birds are not refractory to testosterone and normally have sexual activity (Benoit, 1935 a, b, 1938; Benoit and Assenmacher, 1951, 1955, 1959; Benoit et al., 1955). The results obtained demonstrate more particularly that the SCO has a certain sensitivity to gonadotrophins and gonadal hormones. Indeed when the level of these hormones is increased in the male duck a more or less intense depletion in secretory material and enhanced enzyme activities are observed particularly after LH, FSH and testosterone propionate injections. Depletion in secretory material is generally considered as a manifestation of an enhanced secretory activity (see, for instance, Lenys, 1965, on the base of caryometric measurements). Using autoradiographical techniques, Diederen (1972, 1973) observed a diminished secretory content in SCO cells of frogs whose Reissner's fiber has a greater growth indice. We applied histoenzymological techniques because this parameter could be interesting; it indeed reveals to have some phylogenetic interest (Ziegels, unpublished data). Enhanced D H activities indicate a higher degree of cellular activity, increased acid phosphatase activity may reflect a greater release of secretory material (Farquhar, 1969). At this stage of our investigation, we may not tell whether or not the SCO serves as a target organ for specific hormones. Some general effect mediated through the hypothalamo-hypophyseal system cannot be excluded. At this point we have to mention the work by Varano et al. (1977) who reported comparable observations in Lacerta after ACTH administration. However we have to keep in mind that the SCO may be directly accessible to these hormones since Some tritiated hormonal compounds have been found within structures protected by the blood-brain barrier (Pfaff et al., 1968; Zigrnond et al., 1972; Zigmond, 1975; Pfaff et al., 1976).
40
J. Ziegels:
A relationship between the hypothalamo-hypophyseal system, the epithalamo-epiphyseal and gonadal systems and the SCO is likely.
Acknowledgements The author is indebted to Dr. J. Balthazart of the Department of General and comparative Biochemistry for providing the material.
References
Arvy, L., Fontaine, M., Gabe, M.: Modifications histologiques de l'organe sous-commissural au cours du cycle 6volutif de Salmo salar L. Arch. Anat. micr. Morph. exp. 44, 313--322 (1955). Benoit, J.: Stimulation du d~veloppement testiculaire par l'6clairement artiflciel. C.R. Soc. Biol. 118, 664--668 (1935 a). Benoit, ].: Hypophysectomie et ~clairement artificiel chez le canard mille. C.R. Soc. Biol. 120, 1316--1328 (1935 b). Benoit, J.: Role des yeux et de la vole oculohypophysaire dans la gonadostimulation par la lumi6re artificielle chez le canard domestique. C.R. Soc. Biol. 129, 231--234 ('1938). Benoit, ]., Assenrnacher, I.: l~tude prdliminaire de la vascularisation de l'appareil hypophysaire du canard domestique. Arch. Anat. micr. Morph. exp. 40, 27--45 (1951). Benoit, J., Assenrnacher, I.: Le contr61e hypothalamique de l'activit6 pr6hypophysaire gonadotrope. J. Physiol. (Paris) 47, 427--567 (1955). Benoit, J., Assenrnacher, I.: The control by visible radiations of gonadotropic activity of the duck hypophysis. Rec. Progr. Horm. Res. 15, 143--163 (1959). Benoit, ]., Assenmacher, I., Brard, E.: Apparition et maintien de cycles sexuels non saisonniers chez le canard domestique plac6e pendant plus de trois ans ~ l'obscurit6 totale. J. Physiol. (Paris) 48, 388--391 (1955). Bergstr6rn, R. M., Kivalo, E., Talanti, S., Rinne, U.: The effect of experimental hypothermia on the subcommissural organ of the cat. Biochem. Biol. sperlm. 1, 251--257 (1962). Diederen, J. H. B.: Influence of light and darkness on the subcommissural organ of Rana ternporaria L.: a cytological and autoradiographical study. Z. Zellforsch. 129, 237--255 (1972). Diederen, ]. H. B.: Influence of light and darkness on secretory activity of the subcommissural organ and on growth rate of Reissner's fibre in Rana esculenta L.: a cytological and autoradiographical study. Z. Zeliforsch. 139, 83--94 (1973). DubS, D., LecIerc, R., Pelletier, G., Arirnura, A., Schally, A. V.: Immunohistochemical detection of growth hormone-release inhibiting hormone (somatostatin) in the guinea-pig brain. Cell Tiss. Res. 161, 385--392 (1975).
Subcommissural Organ of Hormone-Injected Ducks
41
Farquhar, M.G.: Lysosome function in regulating secretion: disposal of secretory granules in cells of the anterior pituitary gland. In: Lysosomes in Biology and Pathology, Vol. 2 ('Dingle, J.T., Fell, H.B., eds.), pp. 462--482 (1969). Gerebtzoff, M. A.: Recherches histochimiques et histoenzymologiques sur ta synergie m&abolique entre neurones et n~vroglie dans la cha~ne nerveuse ventrale de la sangsue, Hirudo medicinalis. Bull. Acad. roy. Mdd. Belg. 10, 337--359 (1970). Gerebtzoff, M.A., Brotchi, ].: Localisation et activit& d'enzymes oxydordducteurs dans le nerf et le ganglion rachidien, Ann. Histochim. 11, 63--70 (1966). Kiser, J.S., Palkovits, M., Brownstein, M.J.: Releasing factors in the circumventricular organs of the rat brain. Endocrinology 98, 311--317 (1976). kegait, E.: L'organe sous-commissural chez la grenouille normale et hypophysoprive. C.R. Soc. BioL 140, 543--544 (1946). Legait, H.: L'bydrencdphalocrinie neuros&r&oire chez la poule RhodeIsland au cours du cycle annuel et dans diverses conditions exp&imentales. C.R. Soc. Biol. 149, 1459--1461 (1955). Legait, H., Legait, E.: A p r o p o s de la structure et de l'innervation des organes @endymaires du troisi~me ventricule chez les batraciens et les reptiles. C.R. Soc. Biol. 150, 1982--1984 ('1956). kenys, R.: Contribution ~ l'&ude de la structure et du r61e de l'organe souscommissural. Th~se de doctorat en M4decine, Nancy 1965. Mautner, W.: Studien an der Epiphysis cerebri und am Subcommissuralorgan der FrSsche. Mit Lebensbeobachtung des Epiphysenkreislaus Totalf~irbung des Subcommissuralorgans und Durchtrennung des Reissnerschen Fadens. Z. Zellforsch. 67, 234--270 (1965). Miline, R.: Influence of cold, profound hypothermia and immobilization upon histopbysiology of subcommissural organ. In: Ependyma and Neurohormonal Regulation (Mitro, A., ed.), pp. 77--103. Bratislava: Veda Publishing House of the Slovak Academy of Sciences. 1974. Miline, R., Devecerski, V.: Behaviour of the subcommissural organ under the influence of cold. Symposium tiber circumventrikul~ire Organe, 1975, Schloi~ Reuhardsbrum (in print). Miline, R., Devecerski, V., Sijacki, N.: Uticaj hladnoce na morfodinamiku subkomisuralnog organa. Med. Pregl. 24, 10i--I06 (1971).
Palkovits, M., Brownstein, M.J., Arimura, A., Sato, H., Schally, A.V., Kizer, J. S.: Somatostatin content of the hypothalamic ventromedial and arcuate nuclei and the circumventricular organs in the rat. Brain Res.
109, 430--434 (1976). Pfaff, D. W.: Autoradiographic localization of testosterone-all in the female rat brain and estradiol-SH in the male rat brain. Experientia 24, 958-959 (1968).
P/aft, D. W., Gerlach, ]. L., McEwen, B. S., Ferin, M., Carmel, P., Zimmerman, E.A.: Autoradiographic localization of hormone-concentrating-
42
J. Ziegels: Subcommissural Organ of Hormone-Injected Ducks
cells in the brain of the female Rhesus monkey. J. comp. Neur. I70, 279--294 (1976). Sathyanesan, A.G.: Effect of hypophysectomy and light on the subcommissural organ in some teleosts. Neuroendocrinology 1, 178--183 (1965/66). Shapiro, B.I., Ivanyan, A.K., Nornokonova, L.: Seasonal changes in the nuclei of the anterior hypothalamus, subcommissural organ and epiphysis in bats. Arhk. Anat. Gistol. Embriol. 51, 42--48 (1966). Russian, English summary. Varano, L., Laforgia, V., d'Uva, V., Ciarcia, G., CiarIetta, A.: Effect of ACTH administration on the activity of the subcommissural organ (SCO) of Lacerta in winter. Ninth Conference of European comparative Endocrinologists, Giessen, 1977, Abstracts of papers, p. 10. Ziegels, J.: The vertebrate subcommissural organ: a structural and functional review. Arch. Biol. (Brussels) 87, 429--476 (1976). Zigmond, R.E.: Target cells for gonadal steroids in the brain studies on hormone binding and metabolism. In: Neural and Endocrine Aspects of Behaviour in Birds (Wright, P., Cary, P.G., Volwes, D.M., eds.), pp. 111--121. Elsevier. 1975. Zigmond, R. E., Stern, J. M., McEwen, B. S.: Retention of radioactivity in cell nuclei in the hypothalamus of the ring dove after injection of ~Htestosterone. Gen. comp. Endocr. 18, 450--453 ('1972). Author's address: Dr. J. Ziegels, Institute of Anatomy, 20 rue de Pitteurs, BJ4020 Liege, Belgium.
/V~
J. Neural Transmission 45, 35--42 (1979)
i~mam~dan
9 by Springer-Verlag 1979
Secretory Activity and Histoenzymological Characteristics in the Subcommissural Organ o f H o r m o n e - I n j e c t e d D u c k s , Anas fl/atyrhynchos
J. Ziegels Laboratory of Neuroanatomy, University of Liege, Belgium With 1 Figure Received February 10, 1978
Summary Gonadotrophin and gonadal hormone injections performed on male ducks induce some changes in the activity of the subcommissural organ (SCO). Particularly LH, FSH and testosterone propionate injections are followed by a depletion of secretory material accompanied by increased activities of investigated dehydrogenases and acid phosphatase in SCO cells.
Introduction In a previous paper (Ziegets, 1976) reviewing data on the vertebrate subcommissural organ (SCO), we concluded that it would be interesting to study the relationship between the SCO and the hypothalamo-hypophyseal system. The SCO is considered as part of the epithalamo-epiphyseal system and since the epiphysis has been shown to be involved with gonadal function, we chose to investigate the effects of injections of hypophyseal hormones of the gonadotrophin type and of gonadal hormones on the secretory activity and histoenzymological characteristics of the subcommissural organ. 3':"
0300-9564/79/0045/0035/$ 01.60
36
J. Ziegels: Material and Methods
1. Material Thirty eight months old male ducks, Anas platyrhynchos L., are divided into six groups of five ducks each. They are injected daily, intramuscularly in the posterior limb, for five weeks (during the month of February and the first week of March). During the first three weeks, they receive: First group: control group: 0.2 ml oil. Second group: LH: 1000 IU HCG (LH activity); Primogonyl Schering1 in 0.2 ml oil. Third group: FSH: 200 IU PMS (FSH activity); Anteron Scbering1 in 0.2 ml oil. Fourth group: Testosterone propionate (TP): 10 mg in 0.2 ml oil. Fifth group: Progesterone (P): 10 mg in 0.2 ml oil. Sixth group: EstradioI rnonobenzoate ('EM): 1 mg in 0.2 ml oil. During the last two weeks, injections are administered as before but the third group receives 1000 IU PMS (FSH activity) instead of 200. Finally, 10 days before being sacrificed, the ducks are injected with large doses of hormone, i.e. for each duck: 5000 IU LH, 5000 IU FSH, 50 mg TP, 50 mg P or 5 mg EM in 0.5 ml oil, respectively for the birds of the second, third, fourth, fiith and sixth groups. The ducks of the first control group receive 0.5 ml oil.
2. Methods The SCO of each of the 30 ducks is analysed by the following techniques. Gomori's paraldehyde-fuchsine staining method is used to visualize the secretory material in the SCO. Histoenzymological methods, according to Gerebtzoff and Brotchi (1966) and Gerebtzoff (1970), are performed on fresh quickly frozen tissue samples for the demonstration of the activities of the following enzymes: glucose-6-phosphate dehydrogenase (DH) (pentose shunt), lactate D H (glycolysis), isocitrate D H (Krebs's cycle), glutamate and succino-semialdehyde D H (amino acid metabolism). Standard incubation media contain Tetranitro Blue Tetrazolium as H + acceptor. Barka and Anderson's (1963) technique for the demonstration of acid phosphatase activity is also applied.
Results
1. Effects on the Secretory Material Following hormone injections, quantitative changes in the secretory material, as well as changes in its distribution throughout the 1 Schering: Etablissements M.V.R. Coles, Diegem, Belgium.
Subcommissural Organ of Hormone-Injected Ducks
37
cell, are evident. It is less abundant in LH, FSH and testosterone injected ducks. In estradiol treated birds some depletion is also observed, while in progesterone injected ones the secretory material appears nearly as abundant as in control ducks. Fig. 1 gives an idea of its distribution in each group.
Fig. 1. Secretory material in the SCO of: a control ducks; b LH injected ducks; c FSH injected ducks; d testosterone injected ducks; e progesterone injected ducks; f estradiol injected ducks. • 350
38
J. Ziegels:
2. Effects on Enzyme Activity In the adult male duck, the SCO presents varied histoenzymological patterns. Enzyme activities are sometimes randomly distributed within the cells (succino-semialdehyde DH), sometimes particularly intense in some cellular area as the apical border (succinate DH, glutamate DH, acid phosphatase), the supranuclear region (fast migrating isoenzymes of the lactate DH, isocitrate D H with NAD or NADP as coenzymes, glucose-6-phosphate) or the per• zone (slow migrating isoenzymes of the lactate DH). Following hormone injections we observed some changes in the intensity['bf the preceeding reactions, but no change in the distribution pattern of these enzyme activities. Afker LH, FSH or testosterone propionate injections, most of the enzyme activities are increased. The others are of the same intensity level as the controls. Atker progesterone injections most activities are not altered. In the case of estradiol monobenzoate injections, activities are modified, increased or diminished. These results are gathered in Table 1. T a b l e 1, Enzyme activities A. in the control ducks and after hormone injec-
tions; B. LH: Iuteinizing hormone; C. FSH: follicle stimulating hormone; D. TP: testosterone propionate; E. P: progesterone; F. EM: estradioI monobenzoate Enzyme
A. Control B. LH
C. FSH
D. TP
E. P
F. EM
IF IS ISO N A D ISO N A D P SDH G-6-P GDH SSA A.P.
+ + + + + -4+ + +
§ +++ + + § + + ++ 4- + +++ ++
+++ ++ + + + + +++ + + + +++
+ § + • + ++ + ++ ++
+ ++ • • + + • + ++
++ +++ + + + + ++ + ++ §
IF, IS: isoenzymes of lactate D H : fast moving: IF; slow moving: IS. ISO NAD, ISO N A D P : isocitrate D H with N A D or N A D P as coenzyme. SDH: succinate DH. G-6-P: glucose-6-phosphate DH. G D H : glutamate DH. SSA: succino-semialdehyde DH. A.P: acid phosphatase. + : is considered the standard activity of the SCO of the controls. + + : increase of activity. + + + : interi~e increase of activity. + ; decrease of activity.
Subcommissural Organ of Hormone-Injected Ducks
39
D i s c u s s i o n and Conclusions
Physiological connections between the subcommissural organ and the hypothalamo-hypophyseal system were suggested by different authors (Legait, 1946; Arvy, Fontaine, and Gabe, 1955; Legait, 1955; Legait and Legait, 1956; Bergstr&n et al., 1962; Mautner, 1965; Sathyanesan, 1965; Shapiro et al., 1966; Miline et al., 1971; Miline, 1974; Miline and Devecerski, 1975). Some authors even reported the presence of releasing hormones such as TRH, LH-RH and somatostatin in the SCO (Dub6 et al., 1975; Kizer et al., 1976; Palkovits et al., 1976). We investigated here this relationship in the adult male duck by injecting hormones at a period during which the birds are not refractory to testosterone and normally have sexual activity (Benoit, 1935 a, b, 1938; Benoit and Assenmacher, 1951, 1955, 1959; Benoit et al., 1955). The results obtained demonstrate more particularly that the SCO has a certain sensitivity to gonadotrophins and gonadal hormones. Indeed when the level of these hormones is increased in the male duck a more or less intense depletion in secretory material and enhanced enzyme activities are observed particularly after LH, FSH and testosterone propionate injections. Depletion in secretory material is generally considered as a manifestation of an enhanced secretory activity (see, for instance, Lenys, 1965, on the base of caryometric measurements). Using autoradiographical techniques, Diederen (1972, 1973) observed a diminished secretory content in SCO cells of frogs whose Reissner's fiber has a greater growth indice. We applied histoenzymological techniques because this parameter could be interesting; it indeed reveals to have some phylogenetic interest (Ziegels, unpublished data). Enhanced D H activities indicate a higher degree of cellular activity, increased acid phosphatase activity may reflect a greater release of secretory material (Farquhar, 1969). At this stage of our investigation, we may not tell whether or not the SCO serves as a target organ for specific hormones. Some general effect mediated through the hypothalamo-hypophyseal system cannot be excluded. At this point we have to mention the work by Varano et al. (1977) who reported comparable observations in Lacerta after ACTH administration. However we have to keep in mind that the SCO may be directly accessible to these hormones since Some tritiated hormonal compounds have been found within structures protected by the blood-brain barrier (Pfaff et al., 1968; Zigrnond et al., 1972; Zigmond, 1975; Pfaff et al., 1976).
40
J. Ziegels:
A relationship between the hypothalamo-hypophyseal system, the epithalamo-epiphyseal and gonadal systems and the SCO is likely.
Acknowledgements The author is indebted to Dr. J. Balthazart of the Department of General and comparative Biochemistry for providing the material.
References
Arvy, L., Fontaine, M., Gabe, M.: Modifications histologiques de l'organe sous-commissural au cours du cycle 6volutif de Salmo salar L. Arch. Anat. micr. Morph. exp. 44, 313--322 (1955). Benoit, J.: Stimulation du d~veloppement testiculaire par l'6clairement artiflciel. C.R. Soc. Biol. 118, 664--668 (1935 a). Benoit, ].: Hypophysectomie et ~clairement artificiel chez le canard mille. C.R. Soc. Biol. 120, 1316--1328 (1935 b). Benoit, J.: Role des yeux et de la vole oculohypophysaire dans la gonadostimulation par la lumi6re artificielle chez le canard domestique. C.R. Soc. Biol. 129, 231--234 ('1938). Benoit, ]., Assenrnacher, I.: l~tude prdliminaire de la vascularisation de l'appareil hypophysaire du canard domestique. Arch. Anat. micr. Morph. exp. 40, 27--45 (1951). Benoit, J., Assenrnacher, I.: Le contr61e hypothalamique de l'activit6 pr6hypophysaire gonadotrope. J. Physiol. (Paris) 47, 427--567 (1955). Benoit, J., Assenrnacher, I.: The control by visible radiations of gonadotropic activity of the duck hypophysis. Rec. Progr. Horm. Res. 15, 143--163 (1959). Benoit, ]., Assenmacher, I., Brard, E.: Apparition et maintien de cycles sexuels non saisonniers chez le canard domestique plac6e pendant plus de trois ans ~ l'obscurit6 totale. J. Physiol. (Paris) 48, 388--391 (1955). Bergstr6rn, R. M., Kivalo, E., Talanti, S., Rinne, U.: The effect of experimental hypothermia on the subcommissural organ of the cat. Biochem. Biol. sperlm. 1, 251--257 (1962). Diederen, J. H. B.: Influence of light and darkness on the subcommissural organ of Rana ternporaria L.: a cytological and autoradiographical study. Z. Zellforsch. 129, 237--255 (1972). Diederen, ]. H. B.: Influence of light and darkness on secretory activity of the subcommissural organ and on growth rate of Reissner's fibre in Rana esculenta L.: a cytological and autoradiographical study. Z. Zeliforsch. 139, 83--94 (1973). DubS, D., LecIerc, R., Pelletier, G., Arirnura, A., Schally, A. V.: Immunohistochemical detection of growth hormone-release inhibiting hormone (somatostatin) in the guinea-pig brain. Cell Tiss. Res. 161, 385--392 (1975).
Subcommissural Organ of Hormone-Injected Ducks
41
Farquhar, M.G.: Lysosome function in regulating secretion: disposal of secretory granules in cells of the anterior pituitary gland. In: Lysosomes in Biology and Pathology, Vol. 2 ('Dingle, J.T., Fell, H.B., eds.), pp. 462--482 (1969). Gerebtzoff, M. A.: Recherches histochimiques et histoenzymologiques sur ta synergie m&abolique entre neurones et n~vroglie dans la cha~ne nerveuse ventrale de la sangsue, Hirudo medicinalis. Bull. Acad. roy. Mdd. Belg. 10, 337--359 (1970). Gerebtzoff, M.A., Brotchi, ].: Localisation et activit& d'enzymes oxydordducteurs dans le nerf et le ganglion rachidien, Ann. Histochim. 11, 63--70 (1966). Kiser, J.S., Palkovits, M., Brownstein, M.J.: Releasing factors in the circumventricular organs of the rat brain. Endocrinology 98, 311--317 (1976). kegait, E.: L'organe sous-commissural chez la grenouille normale et hypophysoprive. C.R. Soc. BioL 140, 543--544 (1946). Legait, H.: L'bydrencdphalocrinie neuros&r&oire chez la poule RhodeIsland au cours du cycle annuel et dans diverses conditions exp&imentales. C.R. Soc. Biol. 149, 1459--1461 (1955). Legait, H., Legait, E.: A p r o p o s de la structure et de l'innervation des organes @endymaires du troisi~me ventricule chez les batraciens et les reptiles. C.R. Soc. Biol. 150, 1982--1984 ('1956). kenys, R.: Contribution ~ l'&ude de la structure et du r61e de l'organe souscommissural. Th~se de doctorat en M4decine, Nancy 1965. Mautner, W.: Studien an der Epiphysis cerebri und am Subcommissuralorgan der FrSsche. Mit Lebensbeobachtung des Epiphysenkreislaus Totalf~irbung des Subcommissuralorgans und Durchtrennung des Reissnerschen Fadens. Z. Zellforsch. 67, 234--270 (1965). Miline, R.: Influence of cold, profound hypothermia and immobilization upon histopbysiology of subcommissural organ. In: Ependyma and Neurohormonal Regulation (Mitro, A., ed.), pp. 77--103. Bratislava: Veda Publishing House of the Slovak Academy of Sciences. 1974. Miline, R., Devecerski, V.: Behaviour of the subcommissural organ under the influence of cold. Symposium tiber circumventrikul~ire Organe, 1975, Schloi~ Reuhardsbrum (in print). Miline, R., Devecerski, V., Sijacki, N.: Uticaj hladnoce na morfodinamiku subkomisuralnog organa. Med. Pregl. 24, 10i--I06 (1971).
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