Plasma testosterone and 11-ketotestosterone levels of male pacu Piaractus mesopotamicus (Cypriniformes, Characidae)

Gazola, R.; Borella, Maria Inês

doi:10.1590/s0100-879x1997001200017

Cited by 28 publications

(13 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As expected, an increase in E 2 levels during the vitellogenic period was observed in curimbata, similar to the E 2 profiles described in two other species, such as the Piaractus mesopotamicus (Gazola & Borella, 1997) and Prochilodus argenteus (Arantes et al, 2010). The three times lower plasma E 2 levels of CFs compared to those of EPFs found in the present study during early spring were probably associated with the delayed and less intense vitellogenesis in this group.…”

Section: Gonadal Steroidssupporting

confidence: 91%

“…A gradual increase in GSI values following the ovarian maturation process has been widely reported for a number of rheophilic species, including Piaractus mesopotamicus (Gazola & Borella, 1997), Pseudoplatystoma fasciatum Leonardo et al, 2006;Romagosa, 2010), Pseudoplatystoma sp. (Dabrowsky et al, 2008), Salminus hilarii (Honji et al, 2009) and Prochilodus argenteus (Arantes et al, 2010).…”

Section: Gsi and Spawning Seasonmentioning

confidence: 84%

See 1 more Smart Citation

Gonadal steroids levels and vitellogenesis in the formation of oocytes in Prochilodus lineatus (Valenciennes) (Teleostei: Characiformes)

et al. 2012

View full text Add to dashboard Cite

The objective of this study was to obtain information about the possible mechanisms related to poor reproductive performance in tropical rheophilic fish. To that effect, cages (Cs) and earthen ponds (EPs) were used as experimental systems to provide unsuitable and suitable conditions, respectively, for curimbatá (Prochilodus lineatus) breeders. Fish were maintained under experimental conditions for 18 months, and during this period females were randomly sampled every two months for biometric analysis (n=30), blood (n=5/sampling) and ovary (n=5/sampling). After this period EPs females (EPFs) and Cs females (CFs) were submitted to the induced breeding experiments. The results showed that rearing curimbatá for such long time in a cage at this stocking density, reduces its growth, plasma E2 levels and vitellogenesis. During vitellogenesis, the mean plasma estradiol levels of CFs were three times lower than those of EPFs (P<0.01). CFs presented poorer results than EPFs for all the examined parameters of reproductive performance. Taken together these data showed that the reduced estradiol levels during vitellogenesis (and the consequently less intense transition from the previtellogenic to vitellogenic phase) and reduced amounts of yolk are mechanisms associated with the formation of low quality oocytes and shortened and delayed breeding season in this species. Moreover, our data showed that the onset of vitellogenesis (six months before the spawning season) must be considered as a key period related to the formation of oocytes of good quality, and adequate management should be provided throughout the year.Este estudo teve como objetivo gerar informações básicas sobre os possíveis mecanismos relacionados com os resultados desfavoráveis obtidos com o desempenho reprodutivo em peixes reofílicos tropicais. Para isso tanques-rede (Cs) e viveiros escavados (EPs) foram utilizados como sistemas experimentais para propociar respectivamente condições inadequadas e adequadas para reprodutores de Prochilodus lineatus. Os peixes foram mantidos por 18 meses em viveiros escavados (EPs) e tanques-rede (Cs), e durante este período, foram aleatoriamente coletados a cada dois meses para análise biométrica (n=30), coleta de sangue (n=5/tratamento) e amostragem do ovário (n=5/tratamento). Após este período as fêmeas mantidas em EPs (EPFs) e as fêmeas mantidas em Cs (CFs) foram submetidas aos experimentos de reprodução induzida. Os resultados mostraram que manter curimbatás por este período em Cs, na densidade de estocagem utilizada, reduz seu crescimento, níveis plasmáticos de E2 e vitelogênese. Durante a vitelogênese, os níveis plasmáticos de estradiol das CFs foram três vezes menores do que os das EPFs (P <0,01). As CFs apresentaram resultados inferiores aos das EPFs para todos os parâmetros analisados de desempenho reprodutivo. Em conjunto, estes dados mostram que os níveis reduzidos de estradiol durante a vitelogênese (bem como o consequente atraso na transição da fase previtelogênica para a vitelogênica) e as quantidades reduzidas d...

show abstract

Section: Gonadal Steroidssupporting

confidence: 91%

Section: Gsi and Spawning Seasonmentioning

confidence: 84%

Gonadal steroids levels and vitellogenesis in the formation of oocytes in Prochilodus lineatus (Valenciennes) (Teleostei: Characiformes)

et al. 2012

View full text Add to dashboard Cite

show abstract

“…In contrast, E 2 inhibited this activity at similar incubation times and concentrations. Interestingly, these concentrations of 11-KT correspond to the physiological levels reached in some stages of the reproductive cycles of teleost fish (Rosenblum et al 1987, Gazola & Borella 1997, Weltzien et al 2002 while E 2 concentrations, which inhibited activation, were slightly higher in the males and close to the female E 2 concentrations reported previously in some teleost species (Rosenblum et al 1987, Miura et al 1999, Lone et al 2001. Moreover, 11-KT enhanced while E 2 inhibited proIL-1 intracellular accumulation by LPS/DNAstimulated head-kidney acidophilic granulocytes in a dosedependent manner.…”

Section: Discussionsupporting

confidence: 79%

A role for acidophilic granulocytes in the testis of the gilthead seabream (Sparus aurata L., Teleostei)

Chaves-Pozo

Pelegrı́n²,

Mulero³

et al. 2003

Journal of Endocrinology

View full text Add to dashboard Cite

In mammals, a complex interaction between the immune and the reproductive systems has been described, in which testicular immune cells produce cytokines and growth factors which modulate gonad functions, while specific gonad cells influence the immune response in this organ. In this study we describe the presence of acidophilic granulocytes in the testis of the hermaphrodite teleost fish gilthead seabream (Sparus aurata L.) by using a specific monoclonal antibody. During the post-spawning stage of the testis, this cell type appears in the germinal compartment, accumulates interleukin (IL)-1 and does not seem to be involved in the phagocytosis of degenerating cells. Moreover, in vitro, 11-ketotestosterone and 17 -oestradiol, the principal fish sexual steroids, regulate the respiratory burst activity of acidophilic granulocytes obtained from the head-kidney (the bone marrow equivalent in fish) and the intracellular accumulation of IL-1 by these cells. It is likely, therefore, that IL-1 produced by testicular acidophilic granulocytes regulates important functions of the testis in fish.

show abstract

“…The developmental cycle of Sertoli cells in P. mesopotamicus coincides with the increased 11-KT plasma levels in teleost fish (Borg, 1994;Gazola & Borella, 1997;Methven et al, 1992;Norberg et al, 2001;Scott et al, 1980;Weltzien et al, 2002), and are more highly developed in the maximum testis development stage, when the titer of sex steroids is higher, suggesting that, directly or not, the developing germ cells may use Sertoli lipid deposits for their development.…”

Section: Discussionmentioning

confidence: 71%

Morphological changes of Sertoli cells during the male reproductive cycle of the teleost Piaractus mesopotamicus (Holmberg, 1887)

2005

View full text Add to dashboard Cite

An investigation of the histological and ultrastructural changes of Sertoli cells during the male reproductive cycle in Piaractus mesopotamicus was made. The results showed that the Sertoli cell development is closely related with germ cell maturation. Therefore, these cells may have some role in germ cell maturation during the reproductive cycle of this species, whether in forming a tissue framework for the developing spermatogenic cysts, aiding in testes reorganization for a new reproductive cycle, in addition to other possible functions discussed in the text.Key words: spermatogenesis, testes, cyst cells, reproduction. RESUMO Mudanças morfológicas nas células de Sertoli durante o ciclo reprodutivo de machos do teleósteo Piaractus mesopotamicus (Holmberg, 1887)Realizou-se uma investigação das mudanças histológicas e ultra-estruturais das células de Sertoli durante o ciclo reprodutivo de machos de Piaractus mesopotamicus. Os resultados mostraram que o desenvolvimento das células de Sertoli está estritamente relacionado à maturação das células gaméticas. Portanto, as células de Sertoli têm algum papel na maturação das células germinativas durante o ciclo reprodutivo dessa espécie, talvez formando um tecido de sustentação para os cistos espermatogênicos em desenvolvimento, ajudando a reorganização testicular para um novo ciclo reprodutivo, além de outras possíveis funções discutidas no texto.Palavras-chave: spermatogênese, testículos, células do cisto, reprodução.

show abstract

Plasma testosterone and 11-ketotestosterone levels of male pacu Piaractus mesopotamicus (Cypriniformes, Characidae)

Cited by 28 publications

References 13 publications

Gonadal steroids levels and vitellogenesis in the formation of oocytes in Prochilodus lineatus (Valenciennes) (Teleostei: Characiformes)

Gonadal steroids levels and vitellogenesis in the formation of oocytes in Prochilodus lineatus (Valenciennes) (Teleostei: Characiformes)

A role for acidophilic granulocytes in the testis of the gilthead seabream (Sparus aurata L., Teleostei)

Morphological changes of Sertoli cells during the male reproductive cycle of the teleost Piaractus mesopotamicus (Holmberg, 1887)

Contact Info

Product

Resources

About