A radioimmunoassay was developed using I-125-labeled- [Tyr(0)]Locusta-
DH and polyclonal antibodies raised against Locusta-DH(29-46). The ass
ay had a detection limit of 50 pM, and displayed limited crossreactivi
ty for other CRF-related peptides, but not for unrelated peptides. Abo
ut 60% of the total immunoreactive material in locust hemolymph was at
tributable to Locusta-DH. The circulating level of diuretic hormone in
creases fivefold in fed insects, sufficient to stimulate primary urine
production, and is correlated with the duration of the meal. This is
consistent with the role of Locusta-DH in the control of postfeeding d
iuresis. (C) 1997 Elsevier Science Inc.