Histological characterization of cellular types during Scinax fuscovarius oogenesis (Lutz) (Anura, Hylidae)

Autor(es)

Oliveira, C. de ^[1] ; Santos, L. R. de S.

Afiliação do(s) autor(es)

^[1] Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. Instituto de Biociências, Letras e Ciências Exatas. Departamento de Biologia - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Revista Brasileira de Zoologia; v. 21, n. 4, p. 919-923, dez. 2004.
• Área do conhecimento: Ciências Biológicas - Morfologia
• Assunto(s): Ovário Óvulos Vitelogênese Anura Scinax

Resumo

This paper describes morphological characteristics of the ovarian germinative cells of the Scinax fuscovarius (Lutz, 1925). The ovary is organized in primordial germinative cells (oogonia) and follicular structures (ovarian follicle) - oocytes surrounded by follicular cells. Oogonia: their nests are peripherically localized, containing cells with large and oval nucleus. Oocytes I: basophilic cytoplasm; the spherical nucleus presents few nucleoli, one or two; the follicular cells (one tenuous layer) surround these previtellogenic cells. Oocytes II: the cell is larger and the cytoplasm becomes more basophilic; the nucleus presents few nucleoli and contains many chromosomes in the periphery (beginning the perinucleolar stage). Oocytes III: the cytoplasm acquires an intense acidophilia; the peripherical region of cytoplasm is filled with yolk and the internal region has no yolk at all; pigment synthesis begins; the follicular envelope presents three tenuous layers: an inner acellular (vitelline envelope) and two cellular layers (follicle cells). Oocytes IV: a characteristic of this stage is the differentiation between the animal and the vegetal poles; the nucleus in the animal hemisphere and the pigments give the oocyte a color dark brown; the vitellogenesis is intense and the yolk occupies the whole cytoplasm. (AU)

• Processo FAPESP: 02/08016-9 - Ocorrência e morfologia do sistema pigmentar extracutâneo, com ênfase no aparelho reprodutor em anuros: Hyla nana e H. sanborni, Scinax similis e S. fuscovarius (Hylidae), Physalaemus nattereri e P. fuscomaculatus (Leptodactylidae)
• Beneficiário: Classius de Oliveira
• Modalidade de apoio: Auxílio à Pesquisa - Regular