Les variations cytologiques de l'hypophyse distale des femelles de Nectophrynoïdes occidentalis

Zuber-Vogeli, M.

doi:10.1016/0016-6480(68)90065-8

Cited by 12 publications

(8 citation statements)

References 14 publications

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“…The pituitary gland is comparatively small (Vilter et al 1959), and does not differ between virgin females and males after emergence (Zuber-Vogeli 1968). After parturition the volume of the pituitary decreases dramatically, but increases again after emergence and is maximal just before birthing (Vilter et al 1959 (Zuber-Vogeli 1968, Xavier 1971, Zuber-Vogeli and Xavier 1973, Zuber-Vogeli et al 1975.…”

Section: Pituitary Glandmentioning

confidence: 99%

“…After parturition the volume of the pituitary decreases dramatically, but increases again after emergence and is maximal just before birthing (Vilter et al 1959 (Zuber-Vogeli 1968, Xavier 1971, Zuber-Vogeli and Xavier 1973, Zuber-Vogeli et al 1975. They increase in size and activity after emergence and are most active between parturition and ovulation (Zuber-Vogeli and Herlant 1964, Zuber-Vogeli 1968, Zuber-Vogeli and Xavier 1973, Zuber-Vogeli et al 1975. In females they are active during the follicular phase (Xavier 1971) and in males during spermatogenesis (Zuber-Vogeli et al 1975).…”

Section: Pituitary Glandmentioning

confidence: 99%

“…The glycoprotein type 2 cells are scarcely found within the rostro-ventral part of the pituitary (Zuber-Vogeli and Herlant 1964, Zuber-Vogeli and Doerr-Schott 1976), have a well-developed Golgi apparatus and endoplasmic reticulum (Zuber-Vogeli and Doerr-Schott 1976). These cells are not visible during dormancy, are few and small at emergence, and most prominent in July/ August (Zuber-Vogeli 1966, 1968. In females it was assumed either that they may have no function (Zuber-Vogeli and Xavier 1973), or that they are corticotropic cells (Zuber-Vogeli et al 1975, Zuber-Vogeli andDoerr-Schott 1976).…”

Section: Pituitary Glandmentioning

confidence: 99%

“…Zuber-Vogeli (1978) assumed that bromocriptine is hindering the exocytosis of prolactin. Within non-gestating females protein type 1 cells increase in number after emergence (Zuber-Vogeli 1968). In gestating females protein type 1 cells are abundant during dormancy and abundant at emergence (Zuber-Vogeli 1968).…”

Section: Pituitary Glandmentioning

confidence: 99%

“…Within non-gestating females protein type 1 cells increase in number after emergence (Zuber-Vogeli 1968). In gestating females protein type 1 cells are abundant during dormancy and abundant at emergence (Zuber-Vogeli 1968). After birth they increase in number and have a large nucleus, large Golgi apparatus, many mitochondria, a well-developed endoplasmic reticulum and exocytose was observed 16 days after parturition (Zuber-Vogeli 1978).…”

Section: Pituitary Glandmentioning

confidence: 99%

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A review of the reproductive biology of the only known matrotrophic viviparous anuran, the West African Nimba toad, Nimbaphrynoides occidentalis

Sandberger-Loua¹,

Müller²,

Rödel³

2017

ZSE

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Amphibians, and anurans in particular, show the highest diversity of reproductive modes among tetrapods. Nevertheless, viviparity is scarce in anurans and its occurrence is even more often assumed rather than confirmed. Probably the best studied viviparous amphibian is the Nimba toad, Nimbaphrynoides occidentalis. During more than 40 years of research, the Nimba toad's reproductive morphology, endocrine activity of the ovary as well as the pituitary gland, and to some extent the ecological impact (seasonality, humidity, food availability) on reproduction was examined. Due to the Nimba toad's unique reproductive mode, summaries are usually included in reviews discussing amphibian reproduction and articles on reproductive biology often discuss the exceptional reproductive system of Nimba toads. However, to our knowledge a detailed synthesis, summarising all the different original studies on the toad's reproduction, is so far missing. In this paper we review and summarise all available initial publications, which often have been published in French and/or are difficult to access. A short overview is given of the climatic and environmental conditions experienced by Nimba toads and the key findings supporting a "true" viviparous reproduction with matrotrophy (maternal provision of nutrition during the gestation) and pueriparity (birth of juveniles). Then foetal development (morphological, gonad and pituitary development), and the female (ovary, oviduct, pituitary and their endocrine interactions) and the male reproductive system (testes and pituitary) are reviewed. Finally, the reproductive cycle and its link to the Nimba mountains' seasonality and ecological/ conservation implications are discussed. Key WordsAmphibia development evolution ovary oviduct pueriparity seasonality testes uterus

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Section: Pituitary Glandmentioning

confidence: 99%

Section: Pituitary Glandmentioning

confidence: 99%

Section: Pituitary Glandmentioning

confidence: 99%

Section: Pituitary Glandmentioning

confidence: 99%

Section: Pituitary Glandmentioning

confidence: 99%

See 3 more Smart Citations

A review of the reproductive biology of the only known matrotrophic viviparous anuran, the West African Nimba toad, Nimbaphrynoides occidentalis

Sandberger-Loua¹,

Müller²,

Rödel³

2017

ZSE

View full text Add to dashboard Cite

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Evolution of oviductal gestation in amphibians

Wake

1993

J. Exp. Zool.

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Oviductal retention of developing embryos, with provision for maternal nutrition after yolk is exhausted (viviparity) and maintenance through metamorphosis, has evolved independently in each of the three living orders of amphibians, the Anura (frogs and toads), the Urodela (salamanders and newts), and the Gymnophiona (caecilians). In anurans and urodeles obligate viviparity is very rare (less than 1% of species); a few additional species retain the developing young, but nutrition is yolk-dependent (ovoviviparity) and, at least in salamanders, the young may be born before metamorphosis is complete. However, in caecilians probably the majority of the approximately 170 species are viviparous, and none are ovoviviparous. All of the amphibians that retain their young oviductally practice internal fertilization; the mechanism is cloaca1 apposition in frogs, spermatophore reception in salamanders, and intromission in caecilians. Internal fertilization is a necessary but not sufficient exaptation (sensu Gould and Vrba: Paleobiology 8:4-15, '82) for viviparity. The salamanders and all but one of the frogs that are oviductal developers live at high altitudes and are subject to rigorous climatic variables; hence, it has been suggested that cold might be a "selection pressure" for the evolution of egg retention. However, one frog and all the live-bearing caecilians are tropical low to middle elevation inhabitants, so factors other than cold are implicated in the evolution of live-bearing. Viviparity might facilitate life in a rigorous environment, but likely is not "caused by such an existence. o 1993 Wiley-Liss, Inc.

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Die Differenzierungsgenese der TSH-Zellen von Xenopus laevis unter Normalbedingungen und nach Thiouracilbehandlung

Hemme

1972

Z.Zellforsch

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Les variations cytologiques de l'hypophyse distale des femelles de Nectophrynoïdes occidentalis

Cited by 12 publications

References 14 publications

A review of the reproductive biology of the only known matrotrophic viviparous anuran, the West African Nimba toad, Nimbaphrynoides occidentalis

A review of the reproductive biology of the only known matrotrophic viviparous anuran, the West African Nimba toad, Nimbaphrynoides occidentalis

Evolution of oviductal gestation in amphibians

Die Differenzierungsgenese der TSH-Zellen von Xenopus laevis unter Normalbedingungen und nach Thiouracilbehandlung

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