Analyses of the development and glycoproteins present in the ovarian follicles of Poecilia vivipara (Cyprinodontiformes, Poeciliidae)

Abstract

RESUMO.-[Análise do desenvolvimento e das glicoproteínas presentes nos folículos ovarianos de Poecilia vivipara (Cyprinodontiformes, Poeciliidae).] Os apectos morfofuncionais da oogênese do Poecilia vivipara foram estudados nesse trabalho. Esse estudo contribuiu para o aprimoramento das informações sobre a biologia reprodutiva e do desenvolvimento de espécies com fecundação interna, em especial aquelas pertencentes à família Poecilidae. Para tanto, caracterizou-se os estágios de maturação gonadal e desenvolvimento folicular através de análises mesoscópicas, histológicas, histoquímicas e citoquímicas com lectinas. O estudo mesoscópico permitiu a classificação do desenvolvimento ovariano em seis estágios: imaturo, em maturação I, em maturação II, maturo I, maturo II e pós-desova. O exame microscópico dos ovários permitiu a identificação dos oócitos pré-vitelogênicos (OPVt) e vitelogênicos (OVt). Na fase pré-vitelogênese, verificou-se os oócitos tipo I (OI) e tipo II (OII), e na fase vitelogênese, foram encontrados oócitos tipo III (OIII), tipo IV (OIV) e os The morphofunctional aspects of oogenesis of Poecilia vivipara were studied aiming to understand the reproductive biology and development of species with internal fertilization, particularly those belonging to the family Poeciliidae. The stages of gonadal maturation and follicular development were characterized using mesoscopic, histological, histochemical, and lectin cytochemical analyses. Through mesoscopic evaluation the ovarian development was classified in six phases of development: immature, in maturation I, in maturation II, mature I, mature II, and post-spawn. Based on microscopic examination of the ovaries, we identified the presence of oocytes types I and II during the previtellogenic phase and types III, IV, and V during the vitellogenic phase. As oogenesis proceeded the oocyte cytosol increased in volume and presented increased cytoplasmic granule accumulation, characterizing vitellogenesis. The zona radiata (ZR) increased in thickness and complexity, and the follicular epithelium, which was initially thin and consisting of pavimentous cells, in type III oocytes exhibited cubic simple cells. The histochemical and cytochemical analyses revealed alterations in the composition of the molecular structures that form the ovarian follicle throughout the gonadal development. Our study demonstrated differences in the female reproductive system among fish species with internal and external fertilization and we suggest P. vivipara can be used as experimental model to test environmental toxicity. pós-fertilização (OV). Com o avanço da oogênese, o citosol dos oócitos aumentaram em volume, com crescente acúmulo de grânulos citoplasmáticos, caracterizando a vitelogênese. Além disso, a zona radiata (ZR) aumentou de espessura e alterou suas características histocitoquímicas, e o epitélio folicular (EF), inicialmente delgado e constituído por células pavimentosas, nos FOs na fase III tornaram-se cúbico simples. As análises histoquímicas e citoquímicas permitiram diag...

Lectin‐binding pattern of the senegalese sole Solea senegalensis oogenesis

“…S. senegalensis ovarian follicles displayed an increasing complexity in the lectin binding pattern during oogenesis showing different glycoconjugates expression than in other fish species in which lectin histochemistry have been performed (Calabro et al,2008; Mandich et al,2002; Ortiz‐Delgado et al,2008; Prisco et al,2003; Rocha et al,2011; Sarasquete et al,2002a, b).…”

“…In different fish species it has been found that the follicular cells participate to the synthesis of the zona radiata and the yolk constituents (Calabro et al,2008; Prisco et al,2003; Rocha et al,2011; Sarasquete et al,2002a, b).…”

“…Lastly, during hydration stage the coalesced yolk mass expressed also glycoconjugates with internal βGlcNAc and terminal Fucα1,2Galβ1,4GlcNAcβ (KOH‐s‐WGA and UEAI affinity). Changes in lectin binding pattern of yolk globules have been observed during the vitellogenesis of different teleosts (Calabro et al,2008; Mandich,2002; Ortiz‐Delgado et al,2008; Rocha et al,2011). In this study we revealed the presence of sialoglycoconjugates in the yolk granules of early maturation and hydration stages.…”

“…Since lectins have specific binding affinities for the sugar residues of glycoconjugates, they constitute useful tools to investigate glycoconjugate distribution during germ cell differentiation‐development and sperm maturation (Sharon and Lis,2003; Spicer and Schulte,1992). Lectin histochemistry has been applied to study occurrence and distribution of oocyte glycoconjugates in different teleost fish species (Calabro et al,2008; Mandich et al,2002; Ortiz‐Delgado et al,2008; Rocha et al,2011; Sarasquete et al,2002a, b). Few histochemical data are available on S. senegalensis oogenesis (Gutiérrez et al,1985).…”

Quantitative analysis of crypt cell population during postnatal development of the olfactory organ of the guppy, Poecilia reticulata (Teleostei, Poecilidae), from birth to sexual maturity

“…The presence of spermatozeugmata in cysts of the testis and oocytes in late vitellogenic phase (type IV) [see Rocha et al (Rocha et al, 2011) for a detailed description of the various types] in the ovary were used as an index of complete gonadal development. At 90days after birth, ~50% of male guppies were sexually mature (Fig.1A) while ~66% of females were still immature (Fig.1B,C).…”