Ovarian ecdysteroid levels and basal oöcyte development during maturation in the cockroach Blattella germanica (L.)

• Published in: Journal of insect physiology Vol. 38; no. 5; pp. 339,345 - 343,348
• Main Authors: Pascual, N., Cerdá, X., Benito, B., Tomás, J., Piulachs, M.D., Bellés, X.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 1992; Elsevier
• Subjects: 20-hydroxyecdysone; Biochemistry. Physiology. Immunology; Biological and medical sciences; Blattella germanica; Blattellidae; Blattodea; choriogenesis; cockroach; developing oöcyte; follicle cells; Fundamental and applied biological sciences. Psychology; Immunoreactive, ecdysteroids; Insecta; Invertebrates; juvenile hormones; Physiology. Development; vitellogenesis; Immunoreactive, ecdysteroids; vitellogenesis; cockroach; 20-hydroxyecdysone; developing oöcyte; juvenile hormones; choriogenesis; follicle cells; Steroid hormone; Insecta; Blattellidae; Blattella germanica; Ovary; Vitellogenesis; Ecdysteroide; Arthropoda; Female genital system; Development; Invertebrata; Ovarian follicle; Dictyoptera; Oocyte; Juvenile hormone
• ISSN: 0022-1910; 1879-1611
• DOI: 10.1016/0022-1910(92)90058-L

By using enzyme immunoassay techniques we have quatified the ovarian ecdysteroids during the 7-day cycle of oöcyte maturation in Blattella germanica. Immunoreactive ecdysteroid levels were low on days 0–2, increased to higher values on days 3–6, and peaked on day 7 (about 5 ng of 20-hydroxyecdysone equivalents per pair of ovaries). The predominant non-conjugated ovarian ecdysteroid detected by HPLC analysis was 20-hydroxyecdysone. During oöcyte maturation, the dynamics of patency, vitellogenin uptake, increase in follicle cells diameter (suggested to be due to polyploidy), and choriogenesis was studied. A comparison of the ovarian ecdysteroid profile with the succession of physiological processes occurring within the oöcyte maturation cycle suggests that these hormones could be directly or indirectly involved in the control of patency, polyploidy and choriogenesis in the follicle cells.