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Rivera-López JR, Torres-Martínez A, Hernández-Franyutti AA, Uribe MC, Gribbins K. The male reproductive cycle of the brown basilisk Basiliscus vittatus (Squamata: Corytophanidae) from Tabasco, Southern Mexico. J Morphol 2024; 285:e21694. [PMID: 38619230 DOI: 10.1002/jmor.21694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 03/23/2024] [Accepted: 03/30/2024] [Indexed: 04/16/2024]
Abstract
We used histological and morphometric methods to study the testis and associated glands, including the epididymis, ductus deferens, and renal sexual segment (RSS), of specimens of Basiliscus vittatus sampled from Tabasco, Mexico (17.5926° N, 92.5816° W). Samples were collected throughout 1 year, which included the dry (February to May) and rainy (June to January) seasons. Spermatogenesis in B. vittatus is active throughout the year, but a significant increase in the testicular volume, diameters of seminiferous tubules, height of the germinal epithelium, spermiogenesis, and released spermatozoa occur in the dry season. During the rainy season, all aforementioned parameters decreased except the secretory activity of the epididymis and the RSS, which increased concomitant with an increase of the spermatozoa population within the ductus deferens. These data strongly suggest that B. vittatus reproduce year-round, but males exhibit a peak in spermatogenic activity during the dry season and a peak in insemination and/or copulation at the beginning of the rainy season. We highlight the importance of analyzing not only the testis but also accessory ducts and glands when determining the reproductive cycles of reptiles. The reproductive cycle of B. vittatus is discussed in relation to the environmental conditions of Southern Mexico and is compared to that of other squamates.
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Affiliation(s)
- José Rodrigo Rivera-López
- Laboratorio de Biología de la Reproducción Animal, División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Tabasco, Mexico
| | - Aarón Torres-Martínez
- Laboratorio de Biología de la Reproducción Animal, División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Tabasco, Mexico
- Department of Marine Biosciences, Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, Tokyo, Japan
| | - Arlette Amalia Hernández-Franyutti
- Laboratorio de Biología de la Reproducción Animal, División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco, Tabasco, Mexico
| | - Mari Carmen Uribe
- Laboratorio de Biología de la Reproducción Animal, Departamento de Biología Comparada, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Kevin Gribbins
- Department of Biology, University of Indianapolis, Indianapolis, Indiana, USA
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Bento HJ, Ferreira A, Rosa JMA, de Campos CG, da Silva SLR, Curcio FF, Pescador CA, da Paz RCR. Histological aspects of the renal sexual segment of Brazilian snakes of the Boidae family. Anat Histol Embryol 2024; 53:e13049. [PMID: 38702901 DOI: 10.1111/ahe.13049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 04/22/2024] [Accepted: 04/24/2024] [Indexed: 05/06/2024]
Abstract
Snakes represent a wide and diverse group of species and have anatomical particularities, such as the renal sexual segment (RSS), a structure located in the kidneys and formed from the hypertrophy of the urinary ducts and nephrons. This study aims at describing the histological aspects of the RSS of Boa constrictor, Epicrates cenchria and Corallus hortulanus, all of which are Brazilian snake species from the Boidae family. The reproductive system and kidneys of five male specimens of E. cenchria, three male specimens of C. hortulanus and two male specimens of B. constrictor were obtained. Tissue samples were processed histologically and different stains used (Toluidine Blue, Alcian Blue and Periodic Acid Schiff). The histological evaluation of the RSS of E. cenchria, C. hortulanus and B. constrictor shows that the RSS in these species varies when comparing individuals in the reproductive period with those which are not. It also allows for the observation of the segment's secretory activity in animals in the reproductive stage (mature sperm in the lumen of the seminiferous tubules) as well as in those which are not. Finally, the histological evaluation also reveals the variation of the secretion product in individuals in the reproductive period, in those which are not, and also among individuals within the same reproductive stage.
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Affiliation(s)
- Heitor José Bento
- Graduate Program in Veterinary Sciences, School of Veterinary Medicine, Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
- Wildlife Research Laboratory, School of Veterinary Medicine (FAVET), Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
| | - Adelina Ferreira
- Biosciences Institute, Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
| | - Janaina Marcela Assunção Rosa
- Laboratory of Veterinary Pathology, School of Veterinary Medicine (FAVET), Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
| | - Camila Gonçalves de Campos
- Laboratory of Veterinary Pathology, School of Veterinary Medicine (FAVET), Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
| | - Sávio Lucas Rodrigues da Silva
- Laboratory of Veterinary Pathology, School of Veterinary Medicine (FAVET), Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
| | - Felipe Franco Curcio
- Biosciences Institute, Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
| | - Caroline Argenta Pescador
- Laboratory of Veterinary Pathology, School of Veterinary Medicine (FAVET), Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
| | - Regina Celia Rodrigues da Paz
- Graduate Program in Veterinary Sciences, School of Veterinary Medicine, Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
- Wildlife Research Laboratory, School of Veterinary Medicine (FAVET), Federal University of Mato Grosso (UFMT), Mato Grosso, Brazil
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Silva KMP, Almeida-Santos SM, Lobo LM, Bravo-Vega CA, Rici REG, Sasa M. Morphology and seasonality of the sexual segment of the kidney in genus Bothrops snakes. J Morphol 2021; 283:236-249. [PMID: 34951038 DOI: 10.1002/jmor.21439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 12/15/2021] [Accepted: 12/19/2021] [Indexed: 11/06/2022]
Abstract
In Squamata, the sexual segment of the male kidney (SSK) produces secretory granules that are transmitted to the female tract during copulation. Here, we investigate the morphology of SSK in various species of the pitviper-genus Bothrops, a medically relevant clade of Neotropical snakes, using histology, histochemistry, as well as scanning and transmission electron microscopy. We also evaluated the relationship of SSK hypertrophy with spermatogenesis and storage of sperm. The SSK in Bothrops consists of tall columnar epithelial cells filled with electron-dense secretory granules. These granules are apparently released into the lumen by an apocrine secretory process. In general, the ultrastructural morphology of SSK in Bothrops is similar to those described for other pitvipers in the genus Agkistrodon. In most Bothrops males, the SSK produces carbohydrates and proteins, and occurs in all lobes of the kidney, occupying most of the kidney mass. In contrast, intersexual females (with male copulatory organs) of Bothrops insularis had a smaller SSK diameter than males and did not show hypertrophy. The seasonal development of SSK in Bothrops species seems to be driven by environmental factors rather than phylogeny, since sister species exhibited periods of hypertrophy at different months. In most Bothrops males, hypertrophy occurs at various seasons of the year (spring, summer, autumn), even in winter, and seasonal changes in SSK do not necessarily accompany spermatogenesis.
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Affiliation(s)
| | | | - Luís Miguel Lobo
- Laboratório de Ecologia e Evolução, Instituto Butantan, São Paulo, Brazil
| | - Carlos Andrés Bravo-Vega
- Departamento de Ingeniería Biomédica, Grupo de Investigación en Biologia Matemática y Computacional BIOMAC, Universidad de los Andes, Bogotá, Colombia
| | - Rose Eli Grassi Rici
- Programa de Pós-graduação em Anatomia dos Animais Domésticos e Silvestres, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil
| | - Mahmood Sasa
- Instituto Clodomiro Picado, Costa Rica y Museo de Zoología, Centro de Investigaciones en Biodiversidad y Ecología Tropical, Universidad de Costa Rica, San José, Costa Rica
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Resende FCD, Avelar GFD. The sexual segment of the kidney of a tropical rattlesnake, Crotalus durissus (Reptilia, Squamata, Viperidae), and its relationship to seasonal testicular and androgen cycles. J Morphol 2021; 282:1402-1414. [PMID: 34219274 DOI: 10.1002/jmor.21394] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 06/28/2021] [Accepted: 07/03/2021] [Indexed: 11/10/2022]
Abstract
The sexual segment of the kidney (SSK) is a hypertrophied region of the nephron, which occurs in males of most squamate species that have been investigated, at least, during the active season. Many studies have shown that the SSK has a seasonal secretory cycle that could be correlated to the mating season, testicular activity, and androgen synthesis. However, to date, no study has investigated the presence of androgen receptors (AR) in cells of the SSK, nor the relation between the expression of AR, testosterone levels, and testicular condition. The SSK in Crotalus durissus corresponds to the distal segment of the nephron and presents a peak of hypertrophy during the period of testicular activity (spermatogenesis) and high testosterone levels, suggesting that seasonal variation of the SSK might be under the control of androgens. Testosterone concentrations and expression of AR varied seasonally with increased values for both parameters directly correlated to hypertrophy of the SSK. This study is, therefore, the first to target the SSK of a tropical snake and to establish a relationship between the secretory cycle of the SSK, testicular cycle, and levels of androgens. Furthermore, this study is the first to identify the presence of AR in the nucleus of the SSK cells.
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Affiliation(s)
- Flávia Cappuccio de Resende
- Laboratory of Cellular Biology, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.,Scientific Collection of Snakes, Ezequiel Dias Foundation, Belo Horizonte, Minas Gerais, Brazil
| | - Gleide Fernandes de Avelar
- Laboratory of Cellular Biology, Department of Morphology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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Samson S, Bhagya M, Bhadravathi CS, Aranha I. Sexual segment of the kidney of the lizard, Eutropis carinata: A light microscopic and ultrastructural seasonal study. J Morphol 2020; 282:262-277. [PMID: 33320355 DOI: 10.1002/jmor.21302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 11/06/2020] [Accepted: 11/16/2020] [Indexed: 11/09/2022]
Abstract
We studied seasonal variation of the secretory granules in the epithelial cells of the sexual segment of the kidney (SSK) during the annual sexual cycle in the lizard, Eutropis carinata using light and electron microscopy in correlation with measurements of androgen levels. During the breeding phase, the epithelium of the SSK consists of simple columnar cells with basal nuclei. The cytoplasm contains numerous eosinophilic secretory protein and carbohydrate granules, but lacks glycosaminoglycans. These secretory granules develop during the regenerative phase when the circulating testosterone level increase. During the breeding phase, when the circulating testosterone levels are high, three types of secretory granules can be differentiated in the cytoplasm based on size and opacity; electron translucent type I, electron dense type II, and biphasic type III granules. Type II granules are found at various stages of maturity and degeneration/utilization. All types of secretory granules are released through an apocrine process. Microvilli and tight junctions are prominent at the apical portion of the cell. The cytoplasm contains, Golgi complexes, an abundant network of rough endoplasmic reticulum, numerous tubular mitochondria, condensing, mucus filled and empty vacuoles. Intercellular canaliculi are narrow and indistinct during the regenerative and breeding phases, respectively. During the regressed phase, when the circulating testosterone levels are lowest, the cells are found regressed with wide intercellular canaliculi and devoid of secretory granules. Then the cytoplasm contains a few round mitochondria, Golgi and scanty endoplasmic reticulum.
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Affiliation(s)
- Shanthakumar Samson
- Department of Studies in Zoology, Manasagangotri, University of Mysore, Mysuru, Karnataka, India
| | - Mahadevaiah Bhagya
- Department of Studies in Zoology, Manasagangotri, University of Mysore, Mysuru, Karnataka, India
| | - Chandrasekhar Sagar Bhadravathi
- Department of Neuropathology, Electron Microscopy Laboratory, National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru, Karnataka, India
| | - Ivan Aranha
- Department of Zoology, Ahmednagar College, Ahmednagar, Maharashtra, India
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Aldridge RD, Siegel DS, Goldberg SR, Pyron RA. Seasonal Timing of Spermatogenesis and Mating in Squamates: A Reinterpretation. COPEIA 2020. [DOI: 10.1643/ch-19-230] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Robert D. Aldridge
- Department of Biology, Saint Louis University (Emeritus), St. Louis, Missouri 63103; . Send reprint requests to this address
| | - Dustin S. Siegel
- Department of Biology, Southeast Missouri State University, Cape Girardeau, Missouri 63701;
| | | | - R. Alexander Pyron
- Department of Biological Sciences, The George Washington University, Washington, D.C. 20052;
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Melo GC, Nascimento LB, Galdino CAB. Lizard reproductive biology beyond the gonads: An investigation of sperm storage structures and renal sexual segments. ZOOLOGY 2019; 135:125690. [PMID: 31383295 DOI: 10.1016/j.zool.2019.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/17/2019] [Accepted: 05/14/2019] [Indexed: 11/25/2022]
Abstract
In this study, we investigated the reproductive biology of the small lizard Eurolophosaurus nanuzae based on evidence of sperm storage by females and variations of the renal sexual segment (RSS) in males. We found a remarkable occurrence of crypts containing bundles of sperm and secretions in the epithelium of E. nanuzae oviducts. The chemical composition of the secretions associated with the sperm within the crypts was similar to secretions from the oviductal epithelium, which suggests that females can produce substances involved in the maintenance of stored sperm. Female sperm storage does not occur over the span of years for long-term reproduction; the majority of females with stored sperm occurred during the peak and late periods of the reproductive season. We discuss this result in relation to post-copulatory sexual selection strategies in the context of sperm competition for restricted successful fertilisation. In males, testicular activity was continuous, while RSS activity varied seasonally, in synchrony with female reproductive activity. Throughout the reproductive season, the RSS was hypertrophied, with maximum activity during the peak of the reproductive season. The lowest RSS activity occurred when females were not reproductive (non-reproductive season). Considering that RSS secretions are essential for reproduction, an absence or reduction of these secretions during the non-reproductive season may imply the reduced functionality of sperm during this period. Since sperm production continues throughout the whole reproductive cycle in E. nanuzae males, RSS activity could be an important indicator of reproduction, beyond testicular activity.
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Affiliation(s)
- Gabriela C Melo
- Programa de Pós-graduação em Biologia de Vertebrados, Pontifícia Universidade Católica de Minas Gerais, Av. Dom José Gaspar, 500, 30535-901, Minas Gerais, Brazil; Neotropical Lizard Behavioural Ecology Research Group (NeoLiBE), Av. Dom José Gaspar, 500, 30535-901, Minas Gerais, Brazil.
| | - Luciana B Nascimento
- Programa de Pós-graduação em Biologia de Vertebrados, Pontifícia Universidade Católica de Minas Gerais, Av. Dom José Gaspar, 500, 30535-901, Minas Gerais, Brazil
| | - Conrado A B Galdino
- Programa de Pós-graduação em Biologia de Vertebrados, Pontifícia Universidade Católica de Minas Gerais, Av. Dom José Gaspar, 500, 30535-901, Minas Gerais, Brazil; Neotropical Lizard Behavioural Ecology Research Group (NeoLiBE), Av. Dom José Gaspar, 500, 30535-901, Minas Gerais, Brazil
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8
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NOVELLI IARAA, OLIVEIRA PAOLARDE, CASTAÑON MARIACHRISTINAM, SILVA PILARC, SOUSA BERNADETEMDE. Morphological and histological characterization of sexual segment of the kidney in Notomabuya frenata (Cope, 1862) and Aspronema dorsivittatum (Cope, 1862) (Squamata, Mabuyidae). ACTA ACUST UNITED AC 2018; 90:2267-2278. [DOI: 10.1590/0001-3765201820170871] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 01/25/2018] [Indexed: 11/22/2022]
Affiliation(s)
- IARA A. NOVELLI
- Universidade Federal de Juiz de Fora, Brazil; Universidade Federal de Juiz de Fora, Brazil
| | - PAOLA R. DE OLIVEIRA
- Universidade Federal de Juiz de Fora, Brazil; Universidade Federal de Juiz de Fora, Brazil
| | | | - PILAR C. SILVA
- Universidade Federal de Juiz de Fora, Brazil; Universidade Federal Rural do Rio de Janeiro, Brazil
| | - BERNADETE M. DE SOUSA
- Universidade Federal de Juiz de Fora, Brazil; Universidade Federal de Juiz de Fora, Brazil
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Pewhom A, Srakaew N. Microanatomy of the testes and testicular ducts of the butterfly lizard,
Leiolepis ocellata
Peters, 1971 (Reptilia: Squamata: Agamidae) during the active reproductive period. ACTA ZOOL-STOCKHOLM 2018. [DOI: 10.1111/azo.12270] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Akkanee Pewhom
- Department of Zoology, Faculty of Science Kasetsart University Bangkok Thailand
| | - Nopparat Srakaew
- Department of Zoology, Faculty of Science Kasetsart University Bangkok Thailand
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Rojas CA, Barros VA, Almeida-Santos SM. The reproductive cycle of the male sleep snakeSibynomorphus mikanii(Schlegel, 1837) from southeastern brazil. J Morphol 2012. [DOI: 10.1002/jmor.20099] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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11
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Hernández-Franyutti A, Uribe MC. Seasonal spermatogenic cycle and morphology of germ cells in the viviparous lizardMabuya brachypoda(Squamata, Scincidae). J Morphol 2012; 273:1199-213. [DOI: 10.1002/jmor.20050] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Revised: 04/04/2012] [Accepted: 04/13/2012] [Indexed: 11/09/2022]
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12
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Sever DM, Rheubert JL, Gautreaux J, Hill TG, Freeborn LR. Observations on the Sexual Segment of the Kidney of Snakes with Emphasis on Ultrastructure in the Yellow-Bellied Sea Snake, Pelamis platurus. Anat Rec (Hoboken) 2012; 295:872-85. [DOI: 10.1002/ar.22435] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 01/26/2012] [Indexed: 11/09/2022]
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Aldridge R, Jellen B, Siegel D, Wisniewski S. The Sexual Segment of the Kidney. ACTA ACUST UNITED AC 2011. [DOI: 10.1201/b10879-12] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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15
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Gribbins K, Rheubert J. The Ophidian Testis, Spermatogenesis and Mature Spermatozoa. ACTA ACUST UNITED AC 2011. [DOI: 10.1201/b10879-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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Rheubert JL, Murray CM, Siegel DS, Babin J, Sever DM. The sexual segment of hemidactylus turcicus and the evolution of sexual segment location in squamata. J Morphol 2011; 272:802-13. [DOI: 10.1002/jmor.10949] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 11/18/2010] [Accepted: 11/29/2010] [Indexed: 11/11/2022]
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18
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Rheubert JL, McMahan CD, Sever DM, Bundy MR, Siegel DS, Gribbins KM. Ultrastructure of the reproductive system of the black swamp snake (Seminatrix pygaea). VII. spermatozoon morphology and evolutionary trends of sperm characters in snakes. J ZOOL SYST EVOL RES 2010. [DOI: 10.1111/j.1439-0469.2010.00573.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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Siegel DS, Sever DM, Rheubert JL, Gribbins KM. Reproductive Biology of Agkistrodon piscivorus Lacépède (Squamata, Serpentes, Viperidae, Crotalinae). HERPETOLOGICAL MONOGRAPHS 2009. [DOI: 10.1655/08-031.1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Siegel DS, Aldridge RD, Clark CS, Poldemann EH, Gribbins KM. Stress and reproduction in Boiga irregularis with notes on the ultrastructure of the sexual segment of the kidney in squamates. CAN J ZOOL 2009. [DOI: 10.1139/z09-103] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The reproductive tract of wild-caught male Boiga irregularis (Merrem, 1802) (Brown Treesnake) and the changes that result in these tissues from captivity are described. Wild-caught snakes were compared with snakes kept in captivity and sacrificed at approximately 10, 30, 50, and 60+ days. Snakes sacrificed after 10 days in captivity showed no differences in histological appearance or epithelial height in either the testis or sexual segment of the kidney (SSK) compared with wild snakes. Normal spermatogenic stages and SSK ultrastructure were observed in the testes and kidney from wild specimens and captive specimens after 10 days. In terms of the SSK, large electron-dense secretory vacuoles occupied the apices of the epithelial cells, while a basal nucleus, rough endoplasmic reticulum, and Golgi bodies filled the bases of these cells. All SSK cells were actively secretory in a mode that could most accurately be termed apocrine. At time of secretion, released vacuoles become diffuse and the apical membrane ruptures, spilling the SSK contents into the distal nephron lumen. Between 10 and 30 days in captivity, spermatogenesis and secretion in the SSK ceased and the epithelial height of both tissues decreased. At approximately 60 days, testicular epithelial height increased and spermatogenic activity was reestablished. The SSK, however, remained regressed at 60 days.
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Affiliation(s)
- D. S. Siegel
- Department of Biology, Saint Louis University, 3507 Laclede Avenue, St. Louis, MO 63103, USA
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Barrigada, Guam
- Department of Biology, Wittenberg University, Springfield, OH 45501, USA
| | - R. D. Aldridge
- Department of Biology, Saint Louis University, 3507 Laclede Avenue, St. Louis, MO 63103, USA
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Barrigada, Guam
- Department of Biology, Wittenberg University, Springfield, OH 45501, USA
| | - C. S. Clark
- Department of Biology, Saint Louis University, 3507 Laclede Avenue, St. Louis, MO 63103, USA
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Barrigada, Guam
- Department of Biology, Wittenberg University, Springfield, OH 45501, USA
| | - E. H. Poldemann
- Department of Biology, Saint Louis University, 3507 Laclede Avenue, St. Louis, MO 63103, USA
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Barrigada, Guam
- Department of Biology, Wittenberg University, Springfield, OH 45501, USA
| | - K. M. Gribbins
- Department of Biology, Saint Louis University, 3507 Laclede Avenue, St. Louis, MO 63103, USA
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Barrigada, Guam
- Department of Biology, Wittenberg University, Springfield, OH 45501, USA
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Sever DM. Ultrastructure of the reproductive system of the black swamp snake (Seminatrix pygaea). VI. Anterior testicular ducts and their nomenclature. J Morphol 2009; 271:104-15. [DOI: 10.1002/jmor.10784] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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22
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Peptidase activities in the semen from the ductus deferens and uterus of the neotropical rattlesnake Crotalus durissus terrificus. J Comp Physiol B 2009; 179:635-42. [DOI: 10.1007/s00360-009-0345-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Revised: 11/04/2008] [Accepted: 01/31/2009] [Indexed: 10/21/2022]
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23
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Marinho CE, Almeida-Santos SM, Yamasaki SC, Silveira PF. Seasonal variation of peptidase activities in the reproductive tract of Crotalus durissus terrificus. Gen Comp Endocrinol 2009; 160:84-92. [PMID: 19027015 DOI: 10.1016/j.ygcen.2008.10.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Revised: 10/05/2008] [Accepted: 10/26/2008] [Indexed: 11/19/2022]
Abstract
Seasonal quantitative patterns of acid (APA), basic (APB), puromycin-sensitive (APN-PS) and puromycin-insensitive neutral (APN-PI), cystyl (CAP), dipeptidyl IV (DPPIV), type-1 pyroglutamyl (PAP-I) and prolyl-imino (PIP) aminopeptidases and prolyl oligopeptidase (POP) activities in soluble (SF) and solubilized membrane-bound (MF) fractions from ductus deferens, vagina and uterus were studied to evaluate their relationships with the reproductive cycle and the extensive long-term spermatozoa storage (LTSS) of the Neotropical rattlesnake Crotalus durissus terrificus. APB, PIP and POP were detected only in SF, while other peptidases were detected in SF and MF. APB, APN-PI and APN-PS were predominant in most tissues in all seasons. Peptidase activities had a common pattern of increment during the dry season (winter/autumn), which coincides with the mating period (autumn) and LTSS in the female (winter), as well as the reduction of spermatozoa motility and maintenance of fertilization capacity of spermatozoa. The high CAP activity in the soluble fraction of the vagina during winter, compared to summer (time of parturition) and spring, coincides with the relaxation of this tissue. In the soluble fraction, the low PAP-I activity of the ductus deferens coincided with its high activity in the vagina during the winter; and the inverse occurred in summer, which is consistent with the physiological process of preserving spermatozoon viability. In conclusion, the studied peptidase activities had seasonal and tissue-specific characteristics, which suggest a relevant role in the reproductive physiology of C. d. terrificus.
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Marinho CE, Almeida-Santos SM, Carneiro SM, Yamasaki SC, Silveira PF. Peptidase activities in Crotalus durissus terrificus semen. Reproduction 2008; 136:767-76. [DOI: 10.1530/rep-08-0192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
AbstractTo understand the role of peptidases in seminal physiology ofCrotalus durissus terrificus, activity levels of representative enzymes in semen and their sensitivities to inhibitors, cofactors, and peptide hormones were evaluated. The existence of seminal fractions and the association of peptidases with these fractions were also characterized for the first time in snakes. The prominent inhibitors of aminopeptidases (APs) were amastatin for acid, basic, and neutral; bestatin for basic; and diprotin A for dipeptidyl-IV. Cystyl and prolyl-imino APs were similarly susceptible to the majority of these inhibitors. The basic and neutral were characterized as metallo-peptidases, acid AP was activated by MnCl2, and cystyl, prolyl-imino, and type I pyroglutamyl were characterized as sulphydryl-dependent APs. Angiotensin II, vasotocin, bradykinin, fertilization-promoting peptide, and TRH altered the majority of these peptidase activities; these peptides are possible substrates and/or modulators of these peptidases. Peptidase activities were found in all seminal fractions: seminal plasma (SP), prostasome-like (PR) structures, and soluble (S-) and membrane-bound fractions (MFs) of spermatozoa. The levels of activity of each peptidase varied among different seminal fractions. In SP, the higher activities were puromycin-insensitive neutral and basic APs. In PR, the higher activity was puromycin-insensitive neutral AP. In spermatozoa, the higher activity in subcellular SF was puromycin-sensitive neutral, while in MF both puromycin-sensitive and -insensitive neutral APs were equally higher than the other examined peptidases. Data suggested that these peptidases, mainly basic and neutral, have a high relevance in regulating seminal functions ofC. d. terrificus.
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Sever DM, Siegel DS, Bagwill A, Eckstut ME, Alexander L, Camus A, Morgan C. Renal sexual segment of the Cottonmouth snake,Agkistrodon piscivorous (Reptilia, Squamata, Viperidae). J Morphol 2008; 269:640-53. [DOI: 10.1002/jmor.10599] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Siegel DS, Sever DM. Sperm aggregations in femaleAgkistrodon piscivorus (Reptilia:Squamata): A histological and ultrastructural investigation. J Morphol 2008; 269:189-206. [DOI: 10.1002/jmor.10588] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Abstract
The gametes of man and some other Eutheria have been manipulated successfully for practical reasons, but many gaps remain in our basic understanding of the way that they function. This situation stems not least from a failure to recognize the extent to which eutherian spermatozoa and eggs, and elements related to their operation, have come to differ from those of other groups. Novel features in the male that reflect this include a radical design of the sperm head with the acrosome seeming to function primarily in egg-coat binding rather than its lysis, a multifaceted post-testicular sperm maturation and an androgen/low-temperature-regulated system of sperm storage--both tied to the epididymis, a variable male accessory sex gland complex, and descent of the testis and epididymis to a scrotum. In the female, such novelties are represented in a need for sperm capacitation, in an unusual regulation of sperm transport within the oviduct, in the cumulus oophorus and character of the zona pellucida around the small egg, and in a unique configuration of gamete fusion. The collective evidence now suggests that many of these features reflect a new fertilisation strategy or its consequences, with most being causally linked. One initial 'domino' in this regard appears to be the small yolkless state of the egg and its intolerance for polyspermy, as determinants of the unusual mode of oviductal sperm transport and possibly the existence and form of the cumulus oophorus. However, a particularly influential first 'domino' appears to be the physical character of the eutherian zona pellucida. This differs from the egg coats of other animal groups by virtue of a resilient elasticity and thickness. These qualities allow this primary and often only coat to stretch and so persist during later expansion of the blastocyst, usually until close to implantation. At the same time, the dimensions, physical character, and particularly the relative protease-insensitivity of the zona appear to have had profound effects on sperm form and function and, more indirectly, on sperm-related events in the male and the female tract. Marsupials display some similarities and also some strikingly different features, against which the enigmas of the eutherian situation can be evaluated.
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Affiliation(s)
- J Michael Bedford
- Centre for Reproductive Medicine and Infertility, Weill Medical College, Cornell University, New York, NY 10021, USA.
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Tourmente M, Cardozo GA, Guidobaldi HA, Giojalas LC, Bertona M, Chiaraviglio M. Sperm motility parameters to evaluate the seminal quality of Boa constrictor occidentalis, a threatened snake species. Res Vet Sci 2006; 82:93-8. [PMID: 16857223 DOI: 10.1016/j.rvsc.2006.06.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2005] [Revised: 05/29/2006] [Accepted: 06/02/2006] [Indexed: 11/24/2022]
Abstract
Semen quality analysis constitutes a powerful tool to evaluate the fertility potential of males in threatened species. The Argentine boa constrictor or lampalagua (Boa constrictor occidentalis) is a threatened snake species and has been included in Appendix I of CITES. The objective of this work is to characterize the sperm of B. c. occidentalis on the bases of dynamic parameters to improve this species conservation. Dynamic parameters were measured in sperm samples using videomicroscopy and image analysis software. The sperm population showed a high degree of heterogeneity in velocity parameter values and 95% of the cells showed a linear pattern of movement. Studies in other species indicate that the number of motile spermatozoa and their movement speed is directly correlated with fertilization success. This work will help to establish basic parameter values for the evaluation of the reproductive potential of populations of B. c. occidentalis and to resolve questions referred to its reproductive strategies.
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Affiliation(s)
- M Tourmente
- Cátedra de Biología del Comportamiento, Facultad de Ciencias Exactas, Físicas y Naturales - Universidad Nacional de Córdoba, Departamento de Fisiologia, Vélez Sársfield 299, CP 5000 Córdoba, Argentina.
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Femoral secretions and copulatory plugs convey chemical information about male identity and dominance status in Iberian rock lizards (Lacerta monticola). Behav Ecol Sociobiol 2006. [DOI: 10.1007/s00265-005-0153-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Gribbins KM, Happ CS, Sever DM. Ultrastructure of the reproductive system of the black swamp snake (Seminatrix pygaea). V. The temporal germ cell development strategy of the testis. ACTA ZOOL-STOCKHOLM 2005. [DOI: 10.1111/j.1463-6395.2005.00201.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Winne CT, Dorcas ME, Poppy SM. Population Structure, Body Size, and Seasonal Activity of Black Swamp Snakes (Seminatrix pygaea). SOUTHEAST NAT 2005. [DOI: 10.1656/1528-7092(2005)004[0001:psbsas]2.0.co;2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Akbarsha MA, Tamilarasan V, Kadalmani B, Daisy P. Ultrastructural evidence for secretion from the epithelium of ampulla ductus deferentis of the fan-throated lizardSitana ponticeriana Cuvier. J Morphol 2005; 266:94-111. [PMID: 16127705 DOI: 10.1002/jmor.10369] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Among reptiles, an ampulla ductus deferentis has been reported only in Squamata. Fairly detailed studies are available only for two species, the lizard Calotes versicolor (Fam: Agamidae) and the snake Seminatrix pygaea (Fam: Colubridae). The light microscopic study on C. versicolor revealed the ampulla to be a prominent organ, whereas the light and transmission electron microscopic study in S. pygaea revealed it to be discernable only in histological preparations. Further, the epithelium of the ductal portion of vas deferens as well as the ampulla of C. versicolor appears to contribute to the seminal plasma and can also phagocytose dead sperm, whereas in S. pygaea neither of these roles has been established. Thus, we hypothesize that there may be variations in the anatomy, histology, and the role of the vas deferens in general, and the ampulla in particular, of the squamate reptiles. In this study, the ductus deferens of the small fan-throated lizard Sitana ponticeriana (Fam: Agamidae) was subjected to light and transmission electron microscopic analysis. In this lizard the ampulla is more prominent than in C. versicolor. The epithelium of the ductal portion of vas deferens consists of principal cells (with features reflecting roles in endocytosis and phagocytosis of dead sperm), dark cells (which are absent in the epithelium of the ductal portion of vas deferens of snakes), and basal cells. The ampulla of S. ponticeriana is differentiated into storage and glandular portions. The epithelium of the storage portion is like that in the ductal portion of the vas deferens, whereas that of the glandular portion, consisting of dark and light principal cells and foamy cells, is tall and forms into smooth villous folds. All three cell types show evidence for a role in secretion, in all likelihood different from each other, for release into the lumen to contribute to seminal plasma. These cells do not provide evidence of a role in phagocytosis of dead sperm. It appears that within the Squamata, the ductal ampulla differs in structure as well as function. We suggest that the ductal ampulla of agamid lizards is a composite gland of the ampulla ductus deferentis and seminal vesicles of mammals.
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Affiliation(s)
- M A Akbarsha
- Department of Animal Science, School of Life Sciences, Bharathidasan University, Tiruchirappalli 620 024, India.
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Sever DM, Hopkins WA. Renal sexual segment of the ground skink,Scincella laterale (Reptilia, Squamata, Scincidae). J Morphol 2005; 266:46-59. [PMID: 16121401 DOI: 10.1002/jmor.10364] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Mature squamates possess hypertrophied regions of the distal urinary ducts, the renal sexual segment (RSS). The RSS is believed to provide seminal fluid that mixes with sperm and is released into the female cloaca during coitus. This study is the first to describe ultrastructure of the RSS in a lizard collected throughout the active season. The species examined, Scincella laterale, represents the largest family (Scincidae: 1,200 species) of lizards. Although sperm are present in the posterior ductus deferens of male S. laterale throughout the year, an annual spermatogenic cycle occurs that results in spermiation in spring, coinciding with maximum development of the RSS. Female S. laterale may possess stored sperm in vaginal crypts from March-May and large oviductal eggs April-June. Thus, the correlation between mating and RSS activity observed in other squamates is also found in S. laterale. Cytologically, the active RSS consists of columnar cells with numerous apical, electron-dense secretory vacuoles which are released by an apocrine process. The granules stain positively for proteins with bromphenol blue and react with PAS for neutral carbohydrates. After the mating season the RSS undergoes recrudescence and the electron-dense granules are replaced by a mucoid secretion that characterizes more proximal portions of the nephric tubules throughout the year. Little variation in ultrastructure of the RSS occurs between S. laterale and Cnemidophorus lemniscatus (Teiidae), the only other lizard in which seasonal variation of the RSS has been studied using similar methods. Females exhibit differentiation similar to that of males in the distal urinary tubules, but to a lesser degree. This is only the second such report for female squamates, and the differentiation of the region in females is proposed to result from adrenal androgens.
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Affiliation(s)
- David M Sever
- Department of Biological Sciences, Southeastern Louisiana University, Hammond, Louisiana 70402, USA.
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Sever DM. Ultrastructure of the reproductive system of the black swamp snake (Seminatrix pygaea). IV. Occurrence of an ampulla ductus deferentis. J Morphol 2004; 262:714-30. [PMID: 15487021 DOI: 10.1002/jmor.10272] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The distal end of the ductus deferens of Seminatrix pygaea (Cope) differs from more proximal portions of the tube by possessing a highly fluctuated epithelium. Similar morphology has been reported in this area in one lizard and some mammals and the region has been designated in these taxa as the ampulla ductus deferentis. In this study, light and transmission electron microscopy were used to study the posterior ductus deferens in S. pygaea and compare the histology in this region to more proximal regions of the duct and to descriptions of the ampulla of other species. Seminatrix pygaea stores sperm throughout the ductus deferens during the entire year. The epithelium of the ductus deferens is not secretory, but the presence of numerous small apical vesicles indicates a role in fluid absorption. In addition to the highly folded epithelium, clusters of sperm nuclei are more intimately associated with the apical ampullary epithelium than elsewhere in the ductus deferens. No evidence of phagocytosis of sperm was found. In contrast, the ampulla of mammals and presumably the lizard Calotes versicolor is glandular and phagocytic. The common character shared by the squamates and mammals with specializations in this area is the folded epithelium, and whether this is due to shared ancestry with amniotes or is homoplastic is unresolved.
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Affiliation(s)
- David M Sever
- Department of Biological Sciences, Southeastern Louisiana University, Hammond, Louisiana.
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Almeida-Santos SM, Laporta-Ferreira IL, Antoniazzi MM, Jared C. Sperm storage in males of the snake Crotalus durissus terrificus (Crotalinae: Viperidae) in southeastern Brazil. Comp Biochem Physiol A Mol Integr Physiol 2004; 139:169-74. [PMID: 15528165 DOI: 10.1016/j.cbpb.2004.08.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2004] [Revised: 08/20/2004] [Accepted: 08/24/2004] [Indexed: 10/26/2022]
Abstract
Seasonal variations in spermatozoa numbers and in sperm motility along the vas deferens in Crotalus durissus terrificus from southeastern Brazil were analyzed. Our data demonstrate storage and motility of the spermatozoa along the vas deferens throughout the year. This is characteristic of a postnuptial reproductive cycle, usually found in snakes living in temperate climates. We describe similarities in reproductive cycle patterns found in the tropical nonhibernator C. durissus terrificus and in hibernator snakes from temperate zones. Our results show that in C. durissus terrificus, a significant difference in spermatozoa counts occurs between winter and summer. Higher numbers of spermatozoa in summer and autumn, due to intense spermiogenesis, coincides with the mating season in autumn. These data indicate that after spermiogenesis in summer, the males combine the peak of sperm storage to the period females are attractive. Mating, however, is not linked to ovulation, and the sperm is stored in the females during winter until fertilization occurs in spring. In the males, after mating, spermatozoon counts low. In spring, they gradually increase, turning again the highest in summer and autumn. During spermiogenesis in the convoluted vas deferens, spermatozoa gain motility, enhancing their performance along their way towards the distal portion.
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Affiliation(s)
- Selma M Almeida-Santos
- Laboratory of Herpetology, Instituto Butantan, Av. Dr Vital Brazil 1500, CEP 05503-900, São Paulo, Brazil
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Krohmer RW. Variation in seasonal ultrastructure of sexual granules in the renal sexual segment of the Northern Water Snake,Nerodia sipedon sipedon. J Morphol 2004; 261:70-80. [PMID: 15164368 DOI: 10.1002/jmor.10229] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The renal sexual segment of the kidney (RSS) can be found in many male squamate reptiles, encompassing the distal region of the nephron and, in some cases, collecting ducts. This sexually dimorphic structure exhibits varying degrees of hypertrophy and regression throughout the year. Although researchers have been aware of and have investigated this unique structure for over a century, its ultimate function remains under discussion. In many studies hypertrophy and regression of the RSS have been correlated with testicular activity and androgen secretion. As in most of the snakes studied to date, the male Northern Water Snake (Nerodia s. sipedon) does not exhibit a dramatic cycle of hypertrophy and regression, as reported in lizards. Following the initial hypertrophy at maturity, the male Northern Water Snake maintains a level of RSS hypertrophy throughout the year. Variations in the appearance and makeup of the sexual granules provide an identifiable and quantifiable seasonal pattern that can be correlated with the concentration of plasma androgens. In the Northern Water Snake, plasma androgens are elevated upon emergence and the RSS epithelial cells are filled with solid granules. As androgen levels decline during spring, sexual granule content appears to be breaking down (utilized?), becoming diffuse in appearance. By mid- to late summer androgen synthesis is at a maximum, increasing circulating androgens and stimulating the development and return of the solid granules. This study utilized electron microscopy and steroid radioimmunoassay to examine seasonal cycles of sex granules, in terms of development, maintenance, and regression, correlated with plasma androgen concentration. In addition, this investigation provides evidence of a possible secondary source of androgen secretion.
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Affiliation(s)
- Randolph W Krohmer
- Department of Biological Sciences, Saint Xavier University, Chicago, Illinois 60655, USA.
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