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Gredar T, Leonardi A, Novak M, Sepčić K, Mali LB, Križaj I, Kostanjšek R. Vitellogenin in the European cave salamander, Proteus anguinus: Its characterization and dynamics in a captive female as a basis for non-destructive sex identification. Comp Biochem Physiol B Biochem Mol Biol 2019; 235:30-37. [PMID: 31170475 DOI: 10.1016/j.cbpb.2019.05.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 05/21/2019] [Accepted: 05/28/2019] [Indexed: 11/29/2022]
Abstract
Vitellogenin (Vtg) is a precursor protein of egg yolk proteins in oviparous and ovoviviparous vertebrates. Except in a case of exposure to estrogenic endocrine disruptors, Vtg is a female-specific protein and could be used as a molecular marker for sex identification. This would be especially useful in the case of the endangered European cave salamander Proteus anguinus in which sexes are indistinguishable according to external morphology, which hinders the establishment of a successful captive breeding program. Here we describe the identification, partial characterization, and purification of Vtg from P. anguinus. Vtg was identified in the plasma of a vitellogenic proteus female with visible oocytes. The identification of this protein was accomplished by mass spectrometry analysis. Two-dimensional gel electrophoresis revealed proteus Vtg as a mix of 190 kDa isoforms with isoelectric points in the pH range 5.3-6.0. Vtg was purified from proteus blood by gel filtration followed by anion-exchange chromatography. Using specific staining of SDS-PAGE gels, the Vtg was found to be phosphorylated and lipidated. Unlike the case in some other aquatic vertebrates, in P. anguinus, Vtg was not present in detectable amounts in cutaneous mucus. Degradation of oocytes in the captive vitellogenic female was accompanied by simultaneous decrease of Vtg concentration. Over a period of 10 months, the concentration of Vtg dropped from maximal to sub-detectable. Our results show that Vtg is a promising molecular marker for sex identification and ovary maturation in P. anguinus, which could contribute to the development of a viable program for captive reproduction of this unique species.
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Affiliation(s)
- Tajda Gredar
- Department of Biology, Biotechnical faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia.
| | - Adrijana Leonardi
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - Maruša Novak
- Department of Biology, Biotechnical faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia.
| | - Kristina Sepčić
- Department of Biology, Biotechnical faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia.
| | - Lilijana Bizjak Mali
- Department of Biology, Biotechnical faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia.
| | - Igor Križaj
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia.
| | - Rok Kostanjšek
- Department of Biology, Biotechnical faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia.
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Assis VR, Titon SCM, Gomes FR. Acute stress, steroid plasma levels, and innate immunity in Brazilian toads. Gen Comp Endocrinol 2019; 273:86-97. [PMID: 29750968 DOI: 10.1016/j.ygcen.2018.05.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 04/20/2018] [Accepted: 05/07/2018] [Indexed: 10/17/2022]
Abstract
Stress from habitat fragmentation has been shown to impact amphibian declines. Studies from a variety of vertebrates indicate that stressed animals exhibit an acute increase in circulating plasma glucocorticoid (GC) levels and consequent immunomodulation. To further explore the relationship between GCs and immunity, we subjected three species of newly captured Brazilian toads, Rhinella ornata, R. icterica and R. schneideri to restraint with or without movement restriction (maintenance in a moistened cloth bag vs. maintenance in a bin) for 24 h. We compared various parameters from baseline (field conditions) with values after restraint, including those associated with stress (corticosterone [CORT] plasma levels), and the neutrophil/lymphocyte ratio [N:L ratio]), potential reproduction (testosterone [T] plasma levels), and innate immunity (bacterial killing ability [BKA]). General responses to the restraint challenge (baseline vs. restraint) included increased CORT levels and N:L ratio, and decreased T levels and BKA. Additionally, CORT levels and N:L ratio tended to increase more from restraint with movement restriction than to restraint without movement restriction, indicating toads showed increased stress response to the more intense stressor. All variables showed interspecific variation at baseline conditions: R. ornata had higher CORT levels when compared to the other two species, while R. icterica had the highest BKA values. After restraint (with or without movement restriction), R. ornata displayed higher values for T and N:L ratio, and showed higher CORT values after restraint without movement restriction; however, the CORT values were similar among species after restraint with movement restriction. In terms of immunity, in response to restraint, BKA was different among species only after restraint with movement restriction, with R. schneideri showing the lowest BKA values. Our results show that restraint increases common markers of the stress response, and could reduce potential reproduction and innate immune responses in toads from all studied species. Our results also showed variation at the interspecific level, with the amplitude of change in the studied variables being consistent and more pronounced following restraint with movement restriction for the three-studied species.
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Affiliation(s)
- Vania Regina Assis
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, trav. 14, 101, 05508-900, São Paulo, SP, Brazil.
| | - Stefanny Christie Monteiro Titon
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, trav. 14, 101, 05508-900, São Paulo, SP, Brazil
| | - Fernando Ribeiro Gomes
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, trav. 14, 101, 05508-900, São Paulo, SP, Brazil
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de Assis VR, Navas CA, Mendonça MT, Gomes FR. Vocal and territorial behavior in the Smith frog (Hypsiboas faber): Relationships with plasma levels of corticosterone and testosterone. Comp Biochem Physiol A Mol Integr Physiol 2012; 163:265-71. [DOI: 10.1016/j.cbpa.2012.08.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Revised: 08/05/2012] [Accepted: 08/07/2012] [Indexed: 11/24/2022]
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Eisthen HL, Krause BC. Ambiguities in the relationship between gonadal steroids and reproduction in axolotls (Ambystoma mexicanum). Gen Comp Endocrinol 2012; 176:472-80. [PMID: 22245262 DOI: 10.1016/j.ygcen.2011.12.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 12/25/2011] [Indexed: 11/20/2022]
Abstract
Axolotls (Ambystoma mexicanum) are aquatic salamanders that are widely used in research. Axolotls have been bred in laboratories for nearly 150 years, yet little is known about the basic biology of reproduction in these animals. We investigated the effects of changing day length, time of year, and food availability on levels of circulating estradiol and androgens in adult female and male axolotls, respectively. In addition, we examined the effects of these variables on the mass of ovaries, oviducts, and eggs in females and on mass of testes in males relative to each individual's body weight, to calculate a form of gonadosomatic index (GSI). In both sexes, GSI was not correlated with levels of circulating steroids. In female axolotls, estradiol levels were influenced by food availability, changes in day length, and season, even when animals were held at a constant temperature and day length was decorrelated with calendar date. In addition, the mass of ovaries, oviducts, and eggs varied seasonally, peaking in the winter months and declining during the summer months, even though our animals were not breeding and shedding eggs. In males, levels of androgens appeared to vary independently of external conditions, but GSI varied dramatically with changes in day length. These results suggest that reproduction in axolotls may vary seasonally, as it does in many other ambystomid species, although both male and female axolotls are capable of reproducing several times each year. The physiological basis of this ability remains enigmatic, given the indications of seasonality contained in our data.
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Affiliation(s)
- Heather L Eisthen
- Department of Zoology, Michigan State University, 203 Natural Science Building, East Lansing, MI 48824, United States.
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Marco A, Chivers DP, Kiesecker JM, Blaustein AR. Mate Choice by Chemical Cues in Western Redback (Plethodon vehiculum) and Dunn's (P. dunni) Salamanders. Ethology 2010. [DOI: 10.1111/j.1439-0310.1998.tb00111.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Benner SL, Woodley SK. The reproductive pattern of male dusky salamanders (genus Desmognathus) is neither associated nor dissociated. Horm Behav 2007; 51:542-7. [PMID: 17382330 DOI: 10.1016/j.yhbeh.2007.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Revised: 02/14/2007] [Accepted: 02/15/2007] [Indexed: 11/21/2022]
Abstract
Many seasonally breeding vertebrate species have an associated reproductive pattern: mating behavior, gonadal activity, and peak circulating androgen levels occur simultaneously. In these species, androgens influence the expression of male mating behavior. Other species have a dissociated reproductive pattern: mating behavior occurs at a different time than peak gonadal activity. In such species, it is hypothesized that mating behavior is not dependent on androgen levels [Crews, D., 1984. Gamete production, sex hormone secretion, and mating behavior uncoupled. Horm. Behav. 18, 22-28]. The salamander Desmognathus ochrophaeus mates in the spring and fall while spermatogenesis occurs during the summer, suggesting that it has a dissociated reproductive pattern and that androgens do not mediate mating behavior. To assess whether mating behavior is regulated by gonadal androgens, we castrated males to reduce endogenous androgens and implanted testosterone propionate (TP) to restore androgen levels. Castrated males mated significantly less than did control males. Castrated males given TP mated as much as control males. Compared to controls, circulating androgen levels (both testosterone (T) and dihydrotestosterone (DHT)) were reduced in castrated males and elevated in castrated males given TP implants. We also found that plasma corticosterone (CORT) levels were strongly and positively correlated with T levels. Together, these data indicate that, although spermatogenesis is dissociated in time from mating behavior, androgens are associated with the expression of mating. Thus, the associated-dissociated dichotomy does not adequately describe the reproductive pattern of D. ochrophaeus. We discuss the limitations of the associated-dissociated framework in clarifying hormone-behavior relationships in reptiles and amphibians.
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Affiliation(s)
- Stacey L Benner
- Department of Biological Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282, USA
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Woolley SC, Sakata JT, Crews D. Evolutionary insights into the regulation of courtship behavior in male amphibians and reptiles. Physiol Behav 2004; 83:347-60. [PMID: 15488550 DOI: 10.1016/j.physbeh.2004.08.021] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Comparative studies of species differences and similarities in the regulation of courtship behavior afford an understanding of evolutionary pressures and constraints shaping reproductive processes and the relative contributions of hormonal, genetic, and ecological factors. Here, we review species differences and similarities in the control of courtship and copulatory behaviors in male amphibians and reptiles, focusing on the role of sex steroid hormones, the neurohormone arginine vasotocin (AVT), and catecholamines. We discuss species differences in the sensory modalities used during courtship and in the neural correlates of these differences, as well as the value of particular model systems for neural evolution studies with regard to reproductive processes. For example, in some genera of amphibians (e.g., Ambystoma) and reptiles (e.g., Cnemidophorus), interspecific hybridizations occur, making it possible to compare the ancestral with the descendant species, and these systems provide a window into the process of behavioral and neural evolution as well as the effect of genome size. Though our understanding of the hormonal and neural correlates of mating behavior in a variety of amphibian and reptilian species has advanced substantially, more studies that manipulate hormone or neurotransmitter systems are required to assess the functions of these systems.
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Affiliation(s)
- Sarah C Woolley
- Section for Integrative Biology, Division of Biological Sciences, Patterson Laboratories, University of Texas at Austin, Austin, TX 78712, USA
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Greven H, Schubert-Jung M, Clemen G. The dentition of european Speleomantes spp. (Urodela, Plethodontidae) with special regard to sexual dimorphism. Ann Anat 2004; 186:33-43. [PMID: 14994910 DOI: 10.1016/s0940-9602(04)80116-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Dentigerous bones and dentition of juveniles and adults of several European Speleomantes-species were investigated using scanning electron microscopy. In the juveniles examined, all dentigerous bones bore bicuspid teeth. The adult males showed the well-known dentitional sexual dimorphism, i.e. monocuspid largely conical, elongated and strongly curved premaxillary teeth. However, teeth of the anterior portion of the maxillae and some teeth of the dentary were also clearly monocuspid; the remaining teeth had differently shaped apices considered to be different grades of bicuspidity. Vomerine teeth were exclusively bicuspid. Monocuspid, but smaller teeth were also found on the premaxilla of an adult female. The conical monocuspid tooth in adults is a modified metamorphosed tooth. Monocuspids, at least on the premaxillae, may be constantly present in males and development of monocuspids probably depends on differential sensitivities of the tooth producing tissue for androgen stimuli.
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Affiliation(s)
- Hartmut Greven
- Institut für Zoomorphologie und Zellbiologie der Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany.
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Rooney AA, Crain DA, Woodward AR, Guillette LJ. Seasonal variation in plasma sex steroid concentrations in juvenile American alligators. Gen Comp Endocrinol 2004; 135:25-34. [PMID: 14644641 DOI: 10.1016/j.ygcen.2003.08.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Seasonal variation in plasma sex steroid concentrations is common in mature vertebrates, and is occasionally seen in juvenile animals. In this study, we examine the seasonal pattern of sex hormone concentration in juvenile American alligators (Alligator mississippiensis) and make a limited comparison of these seasonal patterns on two different lakes in Florida. Male juvenile alligators from a reference lake, Lake Woodruff, displayed temporal patterns in plasma testosterone (T) concentrations that appear to be seasonal. A similar pattern in plasma estradiol-17beta (E(2)) was observed in juvenile females from Lake Woodruff. Males had significantly elevated T concentrations during the spring and late summer, whereas females had elevated E(2) in the spring and late summer and significantly depressed E(2) concentrations during the winter. A limited 4-month survey of animals from contaminated Lake Apopka found a lack of such seasonality. These results suggest that: (1) healthy wild populations of juvenile alligators have a prolonged peripubescent period that is marked by seasonal hormonal cycles, (2) juvenile alligators exposed to environmental contaminants can lack such seasonal cyclicity, and (3) future studies of juvenile alligators should incorporate such seasonality into the experimental design.
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Affiliation(s)
- Andrew A Rooney
- Department of Zoology, University of Florida, 223 Bartram Hall, P.O. Box 118525, Gainesville, FL 32611-8525, USA
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Polzonetti-Magni AM, Mosconi G, Soverchia L, Kikuyama S, Carnevali O. Multihormonal control of vitellogenesis in lower vertebrates. INTERNATIONAL REVIEW OF CYTOLOGY 2004; 239:1-46. [PMID: 15464851 DOI: 10.1016/s0074-7696(04)39001-7] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The comparative approach on how and when vitellogenesis occurs in the diverse reproductive strategies displayed by aquatic and terrestrial lower vertebrates is presented in this chapter; moreover, attention has been paid to the multihormonal control of hepatic vitellogenin synthesis as it is related to seasonal changes and to vitellogenin use by growing oocytes. The hormonal mechanisms regulating vitellogenin synthesis are also considered, and the effects of environmental estrogens on the feminization process in wildlife and humans have been reported. It is then considered how fundamental nonmammalian models appear to be, for vitellogenesis research, addressed to clarifying the yolkless egg and the evolution of eutherian viviparity.
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Affiliation(s)
- Alberta Maria Polzonetti-Magni
- Department of Comparative Morphology and Biochemistry, University of Camerino, V. Camerini 2, 62032 Camerino (MC), Italy
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Polzonetti‐Magni AM, Mosconi G, Palermo F, Cottone E, Forno S, Franzoni MF. Amphibians as a model for studying xenoestrogen‐dependent neuroedocrine disruption. ACTA ACUST UNITED AC 2004. [DOI: 10.1080/11250000409356615] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Ehmcke J, Wistuba J, Clemen G, Schlatt S. Targeted expression of androgen receptors in tooth-forming tissues of a neotropical salamander (Bolitoglossa schizodactyla) enables region-specific formation of dimorphic types of teeth in the male. Gen Comp Endocrinol 2003; 134:26-35. [PMID: 13129500 DOI: 10.1016/s0016-6480(03)00216-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Bicuspid teeth are a morphological characteristic in adult metamorphosed urodeles. However, during the mating season the males of many species of plethodontid salamanders (Urodela, Plethodontidae) from northern America bear large monocuspid teeth on their jaws. Since androgen levels are elevated during the mating season, it is likely that the formation of monocuspid teeth is controlled by androgens. However, many plethodontid salamanders from southern Central America live in habitats which lack significant seasonal changes and therefore are no seasonal breeders. These males constantly bear monocuspid teeth, however their presence is restricted to the premaxillary bone, which forms the most frontal element of the upper jaw. Teeth of all other dentigerous bones are bicuspid. This study is based on an immunohistochemical localisation of androgen receptors and reveals a differential expression of androgen receptors in the three separate dental laminae of the upper jaw of Bolitoglossa schizodactyla (Urodela, Plethodontidae) from western Panama. Our findings suggest that the restriction of androgen receptor expression to the premaxillary dental lamina of the male and its absence in all other tooth-forming tissues leads to the differences in tooth morphogenesis. In conclusion, a differential and cell-specific expression of androgen receptors in urodeles-similar to the situation in mammalian species-allows a selective response of differentiating tissues to the hormonal status of the animal.
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Affiliation(s)
- Jens Ehmcke
- Institute of Animal Evolution and Ecology, Hüfferstrasse 1, D-48149 Münster, Germany
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Mosconi G, Cardinali M, Yamamoto K, Kikuyama S, Vellano C, Polzonetti-Magni AM. Temperature-dependent prolactin secretion and reproductive biology of the newt Triturus carnifex Laur. Gen Comp Endocrinol 2002; 126:261-8. [PMID: 12093113 DOI: 10.1016/s0016-6480(02)00001-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The effects of temperature on pituitary prolactin (PRL) gene expression and peripheral levels were studied in both male and female newts obtained from wild conditions during reproductive (Experiment I) and nonreproductive (Experiment II) periods; moreover, changes in parameters related to reproductive function are also described. Male and female newts were taken from a pond in February (Experiment I, reproductive period) and maintained for 1 month in tanks at 4 and 18 degrees C. In male newts kept at 4 degrees C, increase of PRL mRNA in the pituitary and plasma PRL was found compared with that measured in those kept at 18 degrees C. The increase in PRL secretion was parallel to that of plasma androgens and related secondary sexual characteristics (SSC) in males and of plasma estradiol-17beta and vitellogenin in females. On the contrary, in nonreproductive newts (Experiment II), taken from the field in May, no significant changes in plasma PRL, androgens, and SSC were found in those maintained at low temperature (4 degrees C), whereas low temperature significantly increased PRL mRNA expression in the male pituitary and PRL mRNA plus plasma PRL levels in females. These findings suggest that low temperature regulates PRL secretion in this urodele species, showing a sex- and season-related control mechanism; moreover, low temperature failed to influence the reproductive biology of newts taken from the field in May, after naturally occurring reproduction during winter months.
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Affiliation(s)
- Gilberto Mosconi
- Department of Comparative Morphology and Biochemistry, University of Camerino, Via F. Camerini 2, 62032 Camerino MC, Italy
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Mewes KR, Latz M, Golla H, Fischer A. Vitellogenin from female and estradiol-stimulated male river lampreys (Lampetra fluviatilis L.). THE JOURNAL OF EXPERIMENTAL ZOOLOGY 2002; 292:52-72. [PMID: 11754022 DOI: 10.1002/jez.1142] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The influence of estradiol-17beta (E(2)) on vitellogenesis is well documented for a number of oviparous craniates. We have examined the role that estradiol-17beta plays in the induction and regulation of vitellogenin synthesis in the maturing European river lamprey, Lampetra fluviatilis. In both females and males the estradiol-17beta concentrations in the plasma reached comparable maximum values in March, only a few weeks before spawning. Throughout the spawning run, the vitellogenin titer in the blood of females remains rather constant while the ovary volume increases. In contrast, we never found circulating VTG in untreated male lampreys. The synthesis and secretion of the yolk precursor molecule can be induced in males, however, by high doses of estradiol injected into the coelom. Lamprey vitellogenin was isolated from the blood of maturing females as well as from hormone-stimulated males and identified by its immunological and electrophoretic properties. In the blood plasma of both maturing female and estradiol-treated male lampreys it always appears simultaneously in two different molecular forms: a vitellogenin monomer with an apparent molecular weight of 310-330kDa and a dimer. After SDS treatment, vitellogenin is represented as a 212-kDa polypeptide.
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Affiliation(s)
- Karsten Rüdiger Mewes
- Abteilung Experimentelle Morphologie, Institut für Zoologie, Universität Mainz, D-55099 Mainz, Germany.
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Iwata T, Kawahara G, Yamamoto K, Zhou CJ, Nakajo S, Shioda S, Kikuyama S. Effect of prolactin and androgen on the expression of the female-attracting pheromone silefrin in the abdominal gland of the newt, Cynops ensicauda. Biol Reprod 2000; 63:1867-72. [PMID: 11090459 DOI: 10.1095/biolreprod63.6.1867] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Silefrin is a sodefrin-like, female-attracting pheromone comprising 10 amino acids that was isolated from the abdominal gland of the sword-tailed newt, Cynops ensicauda. Hormonal effects on the silefrin precursor mRNA expression and silefrin content in the abdominal gland were investigated in the present study by using Northern blot analysis and radioimmunoassay, respectively. In the abdominal gland of newts treated with prolactin (PRL) plus testosterone propionate (TP), silefrin precursor mRNA expression was markedly enhanced as compared with that in the newts injected with saline, PRL, or TP. Values for radioimmunoassayable silefrin content in the abdominal gland paralleled those for the silefrin precursor mRNA levels. Moreover, silefrin precursor mRNA signals, as revealed by in situ hybridization, as well as stainability of immunoreactive silefrin were much more intense in the epithelial cells of the abdominal gland of the PRL-plus-TP-treated animals than in those of controls. We thus conclude that PRL and androgen are important factors for enhancing silefrin synthesis.
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Affiliation(s)
- T Iwata
- Department of Biology, School of Education, Waseda University, Shinjuku-ku, Tokyo 169-8050, Japan
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Iwata T, Toyoda F, Yamamoto K, Kikuyama S. Hormonal control of urodele reproductive behavior. Comp Biochem Physiol B Biochem Mol Biol 2000; 126:221-9. [PMID: 10874169 DOI: 10.1016/s0305-0491(00)00200-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Hormonal control of expression of courtship behavior and of development of structures related to the reproductive behavior in two species of Japanese newts, Cynops pyrrhogaster and Cynops ensicauda, was described. Prolactin (PRL) and androgen were essential factors for eliciting courtship behavior. In addition, arginine vasotocin markedly enhanced the expression of courtship behavior. PRL induced migration to water, in which courtship and oviposition take place, and converted the integument from the terrestrial type to the aquatic one. PRL also stimulated the growth of the tail fin, which was blocked by estrogen. Cellular and nuclear size and number of synapses on the somata of Mauthner cells, which are involved in tail movement, were also increased by PRL and androgen. Synthesis of sodefrin, a female-attracting pheromone, in the abdominal gland as well as that of mucopolysaccharides constituting the sac of sperm in the lateral gland was enhanced by PRL and androgen. Structural development of oviducts was elicited by estrogen or PRL to a certain extent, and full oviducal development by the combination of these two hormones, PRL being indispensable for the oviducal jelly secretion.
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Affiliation(s)
- T Iwata
- Department of Biology, School of Education, Waseda University, Shinjuku-ku, Nishiwaseda, Tokyo, Japan
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Gobbetti A, Zerani M. In vitro nitric oxide effects on basal and gonadotropin-releasing hormone-induced gonadotropin secretion by pituitary gland of male crested newt (Triturus carnifex) during the annual reproductive cycle. Biol Reprod 1999; 60:1217-23. [PMID: 10208987 DOI: 10.1095/biolreprod60.5.1217] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The objective of this study was to test the possible nitric oxide (NO) involvement in pituitary gonadotropin secretion in the male crested newt, Triturus carnifex. Pituitaries were incubated in vitro with medium alone, GnRH, NO donor (NOd, sodium nitroprusside), NO synthase inhibitor (NOSi, Nomega-nitro-L-arginine methyl ester), cGMP analogue (cGMPa, 8-bromo-cGMP), soluble guanylate cyclase inhibitor (sGCi, cystamine), GnRH plus NOSi, GnRH plus sGCi, and NOd plus sGCi during the annual reproductive cycle: pre-reproduction, reproduction (noncourtship and courtship), and the refractory, recovery, and estivation periods. To determine pituitary gonadotropin secretion indirectly, newt testes were superfused in vitro with preincubated pituitaries, and androgen release was determined. NO synthase (NOS) activity and cGMP levels were assessed in the preincubated pituitaries. Medium alone- and GnRH-preincubated pituitary increased androgen secretion during pre-reproduction, noncourtship, courtship, and recovery; the GnRH-induced increase was higher than the medium alone-induced increase during pre-reproduction, noncourtship, and recovery. NOd and cGMPa increased androgens in all reproductive phases considered except courtship; the NOd- and cGMP-induced increase was higher than the medium alone-induced increase during pre-reproduction, noncourtship, and recovery. NOS activity was highest during courtship and lowest during the refractory and estivation periods. GnRH increased NOS activity during pre-reproduction, noncourtship, and recovery. Cyclic GMP levels were highest during courtship and lowest during the refractory period and estivation. GnRH increased cGMP levels during pre-reproduction, noncourtship, and recovery, while NOd did so during all reproductive phases considered. These results suggest that basal and GnRH-induced gonadotropin secretion are up-regulated by NO in the pituitary gland of the male Triturus carnifex.
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Affiliation(s)
- A Gobbetti
- Department of Molecular, Cellular, and Animal Biology, University of Camerino, 62032 Camerino, Italy.
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Abstract
The role of androgens in vertebrate females has been overlooked until recently. We examine the functional significance of androgens in females by reviewing studies that document relatively high levels of circulating plasma androgens, androgen receptors, or androgen-metabolizing enzymes in females. Among the mechanisms of androgenic action identified are enhanced neuron survival, stimulation of muscle satellite cell proliferation, alteration of ion current kinetics, and release of somatostatin. These mechanisms are not sex specific and thus we hypothesize that androgens play a significant role in normal female development. We encourage study in this nontraditional research area.
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Affiliation(s)
- N L Staub
- Biology Department, Gonzaga University, Spokane, Washington, 99258, USA.
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Gobbetti A, Zerani M, Cardellini LB. Relationships among mammalian gonadotropin-releasing hormone, prostaglandins, and sex steroids in the brain of the crested newt, Triturus carnifex. PROSTAGLANDINS 1992; 44:209-18. [PMID: 1410526 DOI: 10.1016/0090-6980(92)90014-k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The present study was carried out to evaluate the in vitro brain release of prostaglandin F2 alpha (PGF2 alpha), prostaglandin E2 (PGE2), androgens, and 17 beta-estradiol in male and female crested newt, Triturus carnifex, during three different periods of the annual sexual cycle; in addition, the effects of mammalian gonadotropin-releasing hormone (mGnRH), PGF2 alpha, and PGE2 on prostaglandins and steroids release by the brain were evaluated during the same periods. In brain incubations of both sexes, PGF2 alpha and estradiol were higher during postreproduction, while PGE2 and androgens were higher during reproduction. In both sexes, mGnRH increased PGF2 alpha and estradiol during postreproduction, and PGE2 during reproduction; PGF2 alpha increased estradiol secretion during postreproduction. Only in the male, did both mGnRH and PGE2 increase androgens during reproduction. It could be suggested that in Triturus carnifex, the regulation of the reproductive activity in the central nervous system (CNS) depends on the relationships among mGnRH, prostaglandins and steroids. In particular, PGF2 alpha and PGE2 seem to play different roles in the CNS of the newt: PGF2 alpha is involved in the postreproductive processes, through estradiol secretion, while PGE2 in the reproductive ones (through androgens secretion?).
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Affiliation(s)
- A Gobbetti
- Department of Molecular, Cellular and Animal Biology, University of Camerino, Italy
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Gobbetti A, Zerani M. Prostaglandin E2 and reproduction in the male crested newt,Triturus carnifex (Laur.). ACTA ACUST UNITED AC 1992. [DOI: 10.1002/jez.1402630208] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Gobbetti A, Zerani M. Mammalian GnRH involvement in prostaglandin F2 alpha and sex steroid hormones testicular release in two amphibian species: the anuran water frog, Rana esculenta, and the urodele crested newt, Triturus carnifex. Gen Comp Endocrinol 1992; 87:240-8. [PMID: 1398018 DOI: 10.1016/0016-6480(92)90028-i] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The present work was carried out to study the in vitro effects of mammalian gonadotropin-releasing hormone (mGnRH) on Rana esculenta and Triturus carnifex testis production of prostaglandin F2 alpha (PGF2 alpha) and sex steroid hormones during the prereproduction, reproduction, and postreproduction periods. In R. esculenta, testicular PGF2 alpha release was lower during postreproduction, and mGnRH increased PGF2 alpha in prereproduction and reproduction. Androgens were higher during prereproduction, and mGnRH induced an androgens increase in prereproduction and reproduction. In T. carnifex testicular PGF2 alpha release was lower during reproduction, and mGnRH increased PGF2 alpha in prereproduction and reproduction. Androgens were higher in reproduction and lower in postreproduction, and mGnRH induced an androgens increase in reproduction. Estradiol-17 beta release was higher in postreproduction, and mGnRH induced an estradiol decrease in reproduction and an increase in postreproduction. These results seem to indicate the involvement of PGF2 alpha in the testicular reproductive activity, and a similar mGnRH mechanism of action, both in R. esculenta and in T. carnifex. In addition, taken together with previous studies, they seem to suggest that the relationship found between mGnRH and PGF2 alpha or sex steroids could be widespread in amphibians.
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Affiliation(s)
- A Gobbetti
- Department of Molecular, Cellular, Animal Biology, University of Camerino, Italy
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Zerani M, Gobbetti A. In vivo and in vitro studies on the effects of mGnRH on oestradiol-17 beta inter-renal production in the female frog, Rana esculenta, during the post-reproductive period. ACTA PHYSIOLOGICA SCANDINAVICA 1992; 145:377-84. [PMID: 1529724 DOI: 10.1111/j.1748-1716.1992.tb09378.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Plasma oestradiol-17 beta was measured by RIA, in female, Rana esculenta, submitted to hypophysectomy, gonadectomy, or both, and treated with mammalian gonadotropin-releasing hormone (mGnRH), homologous pituitary homogenate, or both, during the post-reproductive period. In addition, the oestradiol-17 beta release was measured in in vitro incubations of ovaries or interrenals treated with mGnRH, pituitary, or both, during the same period. In vivo and in vitro mGnRH and/or pituitary directly stimulated the production of oestradiol-17 beta by the interrenal, but not by ovary, although the stimulatory effects of the pituitary are minor and delayed with respect to those of mGnRH. These results seem to indicate that mGnRH and pituitary, with probably different mechanisms, stimulate the interrenal to produce high levels of oestradiol which is involved in the post-reproductive refractoriness.
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Affiliation(s)
- M Zerani
- Department of Molecular, Cellular and Animal Biology, University of Camerino, Italy
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Cobbetti A, Zerani M. PGF2 alpha, PGE2, and sex steroids from the abdominal gland of the male crested newt Triturus carnifex (Laur.). PROSTAGLANDINS 1992; 43:101-9. [PMID: 1542738 DOI: 10.1016/0090-6980(92)90079-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Prostaglandin F2 alpha (PGF2 alpha), prostaglandin E2 (PGE2), progesterone, androgens, and 17 beta-estradiol in vitro release by the abdominal gland of the crested newt, Triturus carnifex (Laur.), was studied during the prereproductive, reproductive and postreproductive periods. In addition, the in vitro effects of the PGF2 alpha and/or PGE2 on progesterone, androgens and estradiol release by the abdominal gland were evaluated. PGF2 alpha, PGE2 and progesterone release was higher during the reproductive period, and in the same period, PGE2 treatment induced a progesterone increase. PGF2 alpha induced an increase of abdominal gland estradiol release at the end of the reproductive period. These results seemed to confirm the pheromonal role assigned to progesterone, and suggested a PGE2 stimulatory role in inducing progesterone release, even if pheromonal activity of PGF2 alpha and PGE2 cannot be excluded. In addition, PGF2 alpha-dependent estradiol increase at the end of reproduction could be interpreted as a mechanism for interruption of the abdominal gland activity.
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Affiliation(s)
- A Cobbetti
- Department of Molecular, Cellular, and Animal Biology, University of Camerino, Italy
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Gobbetti A, Zerani M, Cardellini LB, Botte V. Plasma prostaglandin F2 alpha and reproduction in the female Triturus carnifex (Laur.). PROSTAGLANDINS 1991; 42:269-77. [PMID: 1780444 DOI: 10.1016/0090-6980(91)90115-v] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Plasma patterns of prostaglandin F2 alpha (PGF2 alpha) and sex hormones (progesterone, androgens and 17 beta-estradiol) have been studied in the female crested newt, Triturus carnifex (Laur.), during the annual sexual cycle. The effects of exogenous PGF2 alpha on sex hormones were determined. In addition, the effects of one week's captivity on plasma PGF2 alpha and sex hormones were reported. PGF2 alpha plasma level peaked in April, was low in summer, and progressively increased during the autumn to peak again in December. The April PGF2 alpha coincided with a 17 beta-estradiol rise, and with a progesterone drop. The autumn PGF2 alpha increase was coupled to a 17 beta-estradiol rise, and therefore it has been tentatively related to ovary and oviduct development. In newts collected in April, moreover, a PGF2 alpha-dependent 17 beta-estradiol synthesis could occur, since PGF2 alpha injection induced a significant 17 beta-estradiol plasma increase. These findings led us to suppose that PGF2 alpha intervenes in spring breeding season termination through the induction of a 17 beta-estradiol synthesis as in other amphibian species. PGF2 alpha injection caused a progesterone decrease, probably by inducing corpora lutea lysis. The patterns of plasma sex hormones were consistent with the results reported for the same newt species.
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Affiliation(s)
- A Gobbetti
- Department of Molecular, Cellular and Animal Biology, University of Camerino, Italy
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Gobbetti A, Zerani M, Botte V. Plasma prostaglandin F2 alpha in the male Triturus carnifex (Laur.) during the reproductive annual cycle and effects of exogenous prostaglandin on sex hormones. PROSTAGLANDINS 1991; 41:67-74. [PMID: 2020747 DOI: 10.1016/0090-6980(91)90106-p] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Plasma patterns of prostaglandin F2 alpha (PGF2 alpha) and sex hormones (progesterone, androgens and 17 beta-estradiol) have been studied in the male crested newt, Triturus carnifex (Laur.), during the sexual cycle. The effects of exogenous PGF2 alpha on sex steroids have also been observed. In addition, effects of one week's captivity are reported. The patterns of plasma sex hormones, during the annual cycle, are consistent with the results previously reported for the same newt species. PGF2 alpha plasma level peaks in April, is low in summer, and progressively increases during autumn to peak again in December. The April PGF2 alpha peak coincides with a plasma estradiol increase and with an androgens drop. In April-collected newts, moreover, PGF2 alpha treatment induces a significant estradiol increase. These findings lead us to suppose that at the end of the breeding season (April) a PGF2 alpha-dependent estradiol synthesis occurs which could be implied in reproductive period termination. In several vertebrates, including some amphibian species, in fact, chronic administration of estradiol results in a strong inhibition of testicular endocrine tissue activity. The putative role of PGF2 alpha-dependent estradiol production in the gonadal regulation in amphibia living in temperate zones is discussed. The autumn PGF2 alpha increase has been tentatively related to the recovery gonadal processes and secondary sexual character development.
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Affiliation(s)
- A Gobbetti
- Department of Cellular Biology, University of Camerino, Italy
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