OVARIAN ECDYSTEROID LEVELS AND BASAL OdCYTE DEVELOPMENT DURING MATURATION IN THE COCKROACH BLATTELL/ GERMANICA (L.)
نویسنده
چکیده
By using enzyme immunoassay techniques we have quantified the ovarian ecdysteroids during the 7-day cycle of olicyte maturation in Blattella germanica. Immunoreactive ecdysteroid levels were low on days O-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 oacyte 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 oiicyte maturation cycle suggests that these hormones could be directly or indirectly involved in the control of patency, polyploidy and choriogenesis in the follicle cells. Key Word Index : Immunoreactive ecdysteroids; 20-hydroxyecdysone; juvenile hormones; developing oiicyte; follicle cells; vitellogenesis; choriogenesis; cockroach
منابع مشابه
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