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Piazza YG, Czuchlej SC, Gómez ML, Meijide FJ. Gonadal morphogenesis in the South American toad Rhinella Arenarum (Anura, Bufonidae) unveils an extremely delayed rate of sex differentiation. J Morphol 2023; 284:e21611. [PMID: 37458081 DOI: 10.1002/jmor.21611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 05/26/2023] [Accepted: 06/06/2023] [Indexed: 07/18/2023]
Abstract
Among anurans, Bufonids are recognized for their retarded sex differentiation. However, few studies have addressed gonadal morphogenesis in this family. Here, we analyzed the early gonadogenesis in laboratory-reared Rhinella arenarum. Few germ cells were identified in the genital ridge at Gosner stage 26. At metamorphosis, somatic cells and germ cells were observed in the outer region of the undifferentiated gonad, whereas the central region was occupied by stromal tissue. A cortico-medullary organization was first recognized on Day 7 postmetamorphosis. The cortex was composed of germ cells and encompassing epithelial cells, whereas the medulla contained cells presumptively derived from the coelomic epithelium. Medullary somatic cells formed metameric knots along the length of the undifferentiated gonad. Consequently, a series of 12-14 gonomeres became recognizable externally. The first sign of ovarian differentiation was observed on Day 15 postmetamorphosis, when a cavity was formed within each gonomere. In contrast, testes were recognized by a uniform distribution of germ cells and intermingled somatic cells, as the division into cortex and medulla was lost. By Day 50 postmetamorphosis, the gonadal metameric organization was still apparent both in the ovaries and testes. Follicles containing diplotene oocytes were observed within the ovary. In the testis, an incipient lobular architecture was recognized without initiation of meiosis within the seminiferous cords. These observations reveal an extremely delayed gonadal development in R. arenarum, not reported previously for other anuran species. In addition, the late differentiation of the gonads contrasted with the early appearance of follicles in the Bidder's organ. Lastly, we observed that delayed metamorphs exhibited an undifferentiated gonad, demonstrating that gonadogenesis in this species is more dependent on somatic development than on age.
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Affiliation(s)
- Yanina G Piazza
- Laboratorio de Ecotoxicología Acuática, DBBE and IBBEA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - Silvia C Czuchlej
- Laboratorio de Ecotoxicología Acuática, DBBE and IBBEA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - María L Gómez
- Instituto de Bio y Geociencias del NOA, CONICET, Centro Científico Tecnológico-Salta, Salta, Argentina
| | - Fernando J Meijide
- Laboratorio de Ecotoxicología Acuática, DBBE and IBBEA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
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Roco ÁS, Ruiz-García A, Bullejos M. Testis Development and Differentiation in Amphibians. Genes (Basel) 2021; 12:578. [PMID: 33923451 PMCID: PMC8072878 DOI: 10.3390/genes12040578] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/08/2021] [Accepted: 04/14/2021] [Indexed: 11/17/2022] Open
Abstract
Sex is determined genetically in amphibians; however, little is known about the sex chromosomes, testis-determining genes, and the genes involved in testis differentiation in this class. Certain inherent characteristics of the species of this group, like the homomorphic sex chromosomes, the high diversity of the sex-determining mechanisms, or the existence of polyploids, may hinder the design of experiments when studying how the gonads can differentiate. Even so, other features, like their external development or the possibility of inducing sex reversal by external treatments, can be helpful. This review summarizes the current knowledge on amphibian sex determination, gonadal development, and testis differentiation. The analysis of this information, compared with the information available for other vertebrate groups, allows us to identify the evolutionarily conserved and divergent pathways involved in testis differentiation. Overall, the data confirm the previous observations in other vertebrates-the morphology of the adult testis is similar across different groups; however, the male-determining signal and the genetic networks involved in testis differentiation are not evolutionarily conserved.
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Affiliation(s)
| | | | - Mónica Bullejos
- Departamento de Biología Experimental, Facultad de Ciencias Experimentales, Campus Las Lagunillas S/N, Universidad de Jaén, 23071 Jaén, Spain; (Á.S.R.); (A.R.-G.)
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Traijitt T, Kitana N, Kitana J. Pattern of Gonadal Sex Differentiation in the Rice Field Frog Hoplobatrachus rugulosus (Anura: Dicroglossidae). Zool Stud 2020; 59:e51. [PMID: 33363623 PMCID: PMC7753241 DOI: 10.6620/zs.2020.59-51] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 08/27/2020] [Indexed: 11/18/2022]
Abstract
Sex differentiation during gonadal development is diversified among anuran amphibian species. In this study, the anuran experimental species Hoplobatrachus rugulosus was examined. The pattern of gonadal sex differentiation was observed by morphological and histological approaches. The gonad was observed morphologically at Gosner stage 33, while distinct testis and ovary were evident from 3-4 weeks after metamorphosis ended. Histological analysis showed that genital ridge formation began at stage 25 and ovarian differentiation began at stage 36. The developing ovary appeared with numerous primary oogonia, which developed into oocytes, while the medulla regressed to form an ovarian cavity. During metamorphosis, only an ovary was observed. Testicular differentiation seemed to begin later, during the first week after metamorphosis, and occurred via an intersex condition. The intersex gonads contained developing testicular tissue with both normal and atretic oocytes. The fully developed testis was first identified at 6 weeks after metamorphosis. Comparing the times of gonadal differentiation and somatic development revealed that the ovary exhibited a basic rate of differentiation while the testis exhibited a retarded one. These results establish that males of this species develop later than do females, and the testis develops through an intersex gonad, as is evident from its seminiferous cord formation, the presence of testis-ova, and atretic oocytes in the tissue. Thus, the pattern of gonadal sex differentiation in H. rugulosus is an undifferentiated type, in which only female gonads are observed during metamorphosis and intersex and male gonads are observed later. These results are crucial for further research on the sexual development of anurans.
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Affiliation(s)
- Thrissawan Traijitt
- Biological Sciences Program, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand. E-mail: (Traijitt)
- Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand. E-mail: (N. Kitana)
| | - Noppadon Kitana
- Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand. E-mail: (N. Kitana)
- BioSentinel Research Group (Special Task Force for Activating Research), Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand. E-mail: (Kitana)
| | - Jirarach Kitana
- Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand. E-mail: (N. Kitana)
- BioSentinel Research Group (Special Task Force for Activating Research), Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand. E-mail: (Kitana)
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Piprek RP, Kloc M, Tassan JP, Kubiak JZ. Development of Xenopus laevis bipotential gonads into testis or ovary is driven by sex-specific cell-cell interactions, proliferation rate, cell migration and deposition of extracellular matrix. Dev Biol 2017; 432:298-310. [PMID: 29080791 DOI: 10.1016/j.ydbio.2017.10.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 10/21/2017] [Accepted: 10/24/2017] [Indexed: 01/10/2023]
Abstract
Information on the mechanisms orchestrating sexual differentiation of the bipotential gonads into testes or ovaries in amphibians is limited. The aim of this study was to investigate the development of Xenopus laevis gonad, to identify the earliest signs of sexual differentiation, and to describe mechanisms driving these processes. We used light and electron microscopy, immunofluorescence and cell tracing. In order to identify the earliest signs of sexual differentiation the sex of each tadpole was determined using genotyping with the sex markers. Our analysis revealed a series of events participating in the gonadal development, including cell proliferation, migration, cell adhesion, stroma penetration, and basal lamina formation. We found that during the period of sexual differentiation the sites of intensive cell proliferation and migration differ between male and female gonads. In the differentiating ovaries the germ cells remain associated with the gonadal surface epithelium (cortex) and a sterile medulla forms in the ovarian center, whereas in the differentiating testes the germ cells detach from the surface epithelium, disperse, and the cortex and medulla fuse. Cell junctions that are more abundant in the ovarian cortex possibly can favor the persistence of germ cells in the cortex. Also the stroma penetrates the female and male gonads differently. These finding indicate that the crosstalk between the stroma and the coelomic epithelium-derived cells is crucial for development of male and female gonad.
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Affiliation(s)
- Rafal P Piprek
- Department of Comparative Anatomy, Institute of Zoology and Biomedical Research, Jagiellonian University, Gronostajowa 9, 30-387 Krakow, Poland.
| | - Malgorzata Kloc
- The Houston Methodist Research Institute, Houston, TX, USA; Department of Surgery, The Houston Methodist Hospital, Houston, TX, USA; University of Texas, MD Anderson Cancer Center, Houston, TX, USA
| | - Jean-Pierre Tassan
- CNRS, UMR 6290, Institute of Genetics and Development of Rennes, Cell Cycle Group, 35043 Rennes, France; Université Rennes 1, Faculty of Medicine, 35043 Rennes, France
| | - Jacek Z Kubiak
- CNRS, UMR 6290, Institute of Genetics and Development of Rennes, Cell Cycle Group, 35043 Rennes, France; Université Rennes 1, Faculty of Medicine, 35043 Rennes, France; Laboratory of Regenerative Medicine and Cell Biology, Military Institute of Hygiene and Epidemiology (WIHE), Warsaw, Poland
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Rozenblut-Kościsty B, Piprek R, Pecio A, Bartmańska J, Szymura JM, Ogielska M. The structure of spermatogenic cysts and number of Sertoli cells in the testes of Bombina bombina and Bombina variegata (Bombinatoridae, Anura, Amphibia). ZOOMORPHOLOGY 2017. [DOI: 10.1007/s00435-017-0362-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Haczkiewicz K, Rozenblut-Kościsty B, Ogielska M. Prespermatogenesis and early spermatogenesis in frogs. ZOOLOGY 2017; 122:63-79. [PMID: 28499702 DOI: 10.1016/j.zool.2017.01.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 01/28/2017] [Indexed: 12/23/2022]
Abstract
Spermatogenesis in frogs was for the first time divided into two phases: prespermatogenesis, when gonocytes proliferate in developing tadpole testes, and active spermatogenesis when spermatogonial stem cells (i.e. descendants of gonocytes), either self-renew or enter into meiotic cycles within cysts formed by Sertoli cells. We argue that amphibian larval gonocytes are homologues to mammalian gonocytes, whereas spermatogonial stem cells (SSCs) in adult frogs are homologous to mammalian single spermatogonia (As). Gonocytes constitute sex cords, i.e. the precursors of seminiferous tubules; they are bigger than SSCs and differ in morphology and ultrastructure. The nuclear envelope in gonocytes formed deep finger-like invaginations absent in SSCs. All stages of male germ cells contained lipid droplets, which were surrounded by glycogen in SSCs, but not in gonocytes. Mitochondria in gonocytes had enlarged edges of cristae, and in SSCs also lamellar mitochondria appeared. Minimal duration of prespermatogenesis was 46days after gonadal sex differentiation, but usually it lasted longer. SSCs give rise to secondary spermatogonia (equal to mammalian A, In, and B). Their lowest number inside a cyst was eight and this indicated the minimal number of cell cycles (three) of secondary spermatogonia necessary to enter meiosis. We sorted them according to the number of cell cycles (from 8 to 256 cells). This number is similar to that recorded for mammals as the result of a single As proliferation. The number of secondary spermatogonia correlates with the volume of a cyst. The general conclusion is that spermatogenesis in amphibians and mammals follows basically the same scheme.
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Affiliation(s)
- Katarzyna Haczkiewicz
- Department of Histology and Embryology, Wrocław Medical University, ul. Chałubińskiego 6a, 50-368 Wrocław, Poland.
| | - Beata Rozenblut-Kościsty
- Department of Evolutionary Biology and Conservation of Vertebrates, University of Wrocław, ul. Sienkiewicza 21, 50-335 Wrocław, Poland
| | - Maria Ogielska
- Department of Evolutionary Biology and Conservation of Vertebrates, University of Wrocław, ul. Sienkiewicza 21, 50-335 Wrocław, Poland.
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Mali PV, Gramapurohit NP. Pattern of gonadal differentiation and development up to sexual maturity in the frogs, Microhyla ornata and Hylarana malabarica: A comparative study. ACTA ACUST UNITED AC 2015; 323:666-78. [PMID: 26361250 DOI: 10.1002/jez.1958] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/15/2015] [Accepted: 07/13/2015] [Indexed: 11/08/2022]
Abstract
Gonadogenesis was studied in Microhyla ornata (Family: Microhylidae) and Hylarana malabarica (Family: Ranidae) up to sexual maturity. Indifferent gonads of M. ornata directly differentiated into either testes or ovaries while those of H. malabarica differentiated into ovaries in all the individuals followed by testicular differentiation in males through an ovarian phase. In some tadpoles of M. ornata, formation of a central cavity at Gosner stage 27 marked ovary differentiation while meiosis was initiated at stage 29. Folliculogenesis was evident at stage 39. Vitellogenesis was initiated in females 9 months post-metamorphosis that attained maturity around 11 months after the completion of metamorphosis. Gonads of males with uniformly distributed germ and somatic cells remained undifferentiated until stage 41. Germ and somatic cells reorganized into seminiferous cords at stage 42. One month after completing metamorphosis, testes contained seminiferous tubules while those of 3 months old males exhibited all spermatogenic stages. In H. malabarica, germ cells entry into meiosis marked ovary differentiation at stage 29 while, ovarian cavity was discernable around stage 35. Post-metamorphosis, ovaries of 1-6 month old females contained pre-diplotene oocytes. Females were immature even 1 year after the completion of metamorphosis. In all the tadpoles, ovaries with central cavity and meiocytes were present up to the completion of metamorphosis. Gonads of prospective males displayed an obliterating ovarian cavity along with degenerating oocytes at the end of metamorphosis. Germ and somatic cells reorganized into seminiferous cords in males 3 months after the completion of metamorphosis. Testes of 4 months old males exhibited distinct seminiferous tubules while those of 6 months old exhibited meiosis. All spermatogenic stages were observed in testes of 9 months old males indicating maturity.
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Affiliation(s)
- Prajakta Vijay Mali
- Department of Zoology, Savitribai Phule Pune University, Ganeshkhind, Pune, India
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Gonadal Differentiation and Development in the Snouted Treefrog,Scinax fuscovarius(Amphibia, Anura, Hylidae). J HERPETOL 2015. [DOI: 10.1670/14-036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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9
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10
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Piprek RP, Pecio A, Szymura JM. Differentiation and Development of Gonads in the Yellow-Bellied Toad,Bombina variegataL., 1758 (Amphibia: Anura: Bombinatoridae). Zoolog Sci 2010; 27:47-55. [DOI: 10.2108/zsj.27.47] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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11
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Fabrezi M, Quinzio SI, Goldberg J. The ontogeny of Pseudis platensis (Anura, Hylidae): Heterochrony and the effects of larval development on postmetamorphic life. J Morphol 2009; 271:496-510. [DOI: 10.1002/jmor.10815] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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12
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El Jamil A, Magre S, Mazabraud A, Penrad-Mobayed M. Early aspects of gonadal sex differentiation in Xenopus tropicalis with reference to an antero-posterior gradient. ACTA ACUST UNITED AC 2008; 309:127-37. [PMID: 18213628 DOI: 10.1002/jez.439] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In an effort to contribute to the development of Xenopus tropicalis as an amphibian model system, we carried out a detailed histological analysis of the process of gonadal sex differentiation and were able to find evidence that gonadal differentiation in X. tropicalis follows an antero-posterior gradient. Although the main reason for the presence of a gradient of sex differentiation is still unknown, this gradient enabled us to define the early events that signal ovarian and testicular differentiation and to identify the undifferentiated gonad structure. Given the various advantages of this emerging model, our work paves the way for experiments that should contribute to our understanding of the dynamics and mechanisms of gonadal sex differentiation in amphibians.
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Affiliation(s)
- Anwar El Jamil
- Institut Jacques Monod, CNRS/Universités Paris 6 et Paris 7, Paris, France
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Ogielska M, Kotusz A. Pattern and rate of ovary differentiation with reference to somatic development in anuran amphibians. J Morphol 2004; 259:41-54. [PMID: 14666524 DOI: 10.1002/jmor.10162] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The rate of somatic development of anuran amphibians is only roughly correlated with the rate of gonad differentiation and varies among species. The somatic stage of a tadpole often does not reflect its age, which seems to be crucial for gonad differentiation rate. We compared the morphology and differentiation of developing ovaries at the light and electron microscopy level, with reference to somatic growth and age of a female. Our observations were performed on 12 species of six families (Rana lessonae, R. ridibunda, R. temporaria, R. arvalis, R. pipiens, R. catesbeiana, Bombina bombina, Hyla arborea, Bufo bufo. B. viridis, Xenopus laevis, Pelobates fuscus) and compared with the results obtained by other authors. This allowed us to describe the unified pattern of anuran female gonad differentiation. Ovary differentiation was divided into 10 stages: I-III, undifferentiated gonad; IV, sexual differentiation; V, first nests of meiocytes; VI, first diplotene oocytes; VII-IX, increasing number of diplotene oocytes and decreasing number of oogonia and nests; X, fully developed ovary composed of diplotene oocytes with rudimental patches of oogonia. We distinguished three types of ovary differentiation rate: basic (most species), retarded (genus Bufo), and accelerated (green frogs of the subgenus Pelophylax genus Rana).
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Affiliation(s)
- Maria Ogielska
- Laboratory of Evolutionary and Developmental Biology of Vertebrates, Zoological Institute, Wroclaw University, 50-335 Wrocław, Poland.
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Gramapurohit NP, Shanbhag BA, Saidapur SK. Pattern of gonadal sex differentiation, development, and onset of steroidogenesis in the frog, Rana curtipes. Gen Comp Endocrinol 2000; 119:256-64. [PMID: 11017773 DOI: 10.1006/gcen.2000.7513] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Histomorphological changes and steroidogenic potential of the gonads during sexual differentiation and development were studied in Rana curtipes from tadpole stage 25 (Gosner) until maturity. In stage 25 tadpoles of smaller snout-vent length (SVL; 4-5 mm) the gonads were indifferent, containing a few somatic and germ cells, whereas in larger tadpoles (SVL > 7 mm) gonads were differentiated into ovaries with a central lumen. Onset of meiosis was seen in these ovaries. At stage 26, diplotene and first growth phase oocytes were found. With advancement in developmental stage and after metamorphosis the ovaries progressively enlarged due to increase in number and size of oocytes. Vitellogenesis began in the ovary of 4-month-old frogs. Females attained maturity 6 months after metamorphosis. The frogs showed amplexus and one frog spawned. Onset of testicular formation seen at stage 31 was associated with the degeneration of oocytes and infiltration of darkly stained somatic cells in the central region. By stage 35 all oocytes degenerated, leaving behind a large number of somatic and germ cells interspersed with each other. At stage 38, formation of seminiferous tubules enclosing spermatogonia and pre-Sertoli cells was seen. Initiation of meiosis was evident at metamorphic climax. Cysts of elongated spermatids associated with Sertoli cells were seen in 45-day-old frogs. Histochemically, delta(5)-3 beta-hydroxysteroid dehydrogenase activity was localized in the ooplasm, follicular cells, and interstitium of the ovary from stage 28 onward. The enzyme activity in the testis appeared in 45-day-old froglets. In R. curtipes gonadal differentiation is a semidifferentiated type since gonads initially differentiate into ovaries, and later, in the prospective males, the ovaries degenerate and transform into testes. The males attain maturity much earlier than the females. In R. curtipes gonadal sex differentiation precedes the onset of gonadal steroidogenesis.
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Affiliation(s)
- N P Gramapurohit
- Department of Zoology, Karnatak University, Dharwad 580 003, India
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Abstract
The brain of adult bullfrogs (Rana catesbeiana) contains six populations of cells which are immunoreactive for the neurohypophysial peptide arginine vasotocin (AVT). It is unknown when some of these cell populations first appear during development and when the sexual differences in AVT distribution first become apparent. We therefore used immunocytochemistry to examine development of AVT pathways in developing bullfrog tadpoles and in newly metamorphosed froglets of both sexes. AVT-immunoreactive (AVT-ir) cells were already present in the three diencephalic areas (magnocellular preoptic nucleus, suprachiasmatic nucleus and hypothalamus) at stage III (Taylor and Kollros stages), the earliest stage examined. Cell size in the magnocellular nucleus was not bimodally distributed in either tadpoles or froglets. AVT-ir cells in the telencephalic septal nucleus and amygdala did not appear until stage VI. There was no sexual difference in the density of AVT-ir cells or fibers in the amygdala of tadpoles or froglets. Finally, cells in the hindbrain pretrigeminal nucleus appeared much later--after stage XX. Thus, different populations of neurons begin to express AVT at unique times during development. The sexual dimorphism in AVT content observed in the amygdala of adult bullfrogs must appear during juvenile development or at adulthood.
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Affiliation(s)
- S K Boyd
- Department of Biological Sciences, University of Notre Dame, IN 46556
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