D. Martin et al., PATTERNS OF HEMOLYMPH VITELLOGENIN AND OVARIAN VITELLIN IN THE GERMAN-COCKROACH, AND THE ROLE OF JUVENILE-HORMONE, Physiological entomology, 20(1), 1995, pp. 59-65
The concentrations of fat body and haemolymph vitellogenin and ovarian
vitellin during the first gonadotropic cycle of the cockroach Blattel
la germanica (L.) (Dictyoptera, Blattellidae) have been studied. For t
hese purposes, a polyclonal antibody against B. germanica vitellogenin
and vitellin has been obtained, and an ELISA to quantify these protei
ns has been developed. Ovarian vitellin levels follow a pattern which
parallels those of basal oocyte growth and Juvenile Hormone production
by the corpora allata. This suggests that Juvenile Hormone regulates
vitellogenin uptake into oocytes. Fat body and haemolymph vitellogenin
levels give cyclic and parallel patterns. However, the cycle of Juven
ile Hormone appears delayed with respect to that of vitellogenin. We s
uggest that the production of Juvenile Hormone, although cyclic in pro
file, does not modulate alone the cycle of vitellogenin. At least a su
pplementary mechanism, apparently independent of Juvenile Hormone, may
be involved in the decline of vitellogenin production at the end of t
he vitellogenic cycle.