ACE-INHIBITOR CAPTOPRIL REDUCES ECDYSTEROIDS AND OVIPOSITION IN MOTHS

Authors: VERCRUYSSE, L. - CROP PROTECTION, GHENT; GELMAN, DALE; RAES,, E. - GHENT UNIV, BELGIUM; HOOGHE, B - GHENT UNIV, BELGIUM; VERMEIRSSEN, V. - GENT UNIV, BELGIUM; VAN CAMP, J. - GHENT UNIV, BELGIUM; SMAGGHE, G. - GHENT UNIV, BELGIUM

Submitted to: European Comparative Endocrinologists
Publication Type: Abstract Only
Publication Acceptance Date: 4/1/2004
Publication Date: 6/1/2004
Citation: Vercruysse, L., Gelman, D.B., Raes,, E., Hooghe, B., Vermeirssen, V., Van Camp, J., Smagghe, G. 2004. Ace-inhibitor captopril reduces ecdysteroids and oviposition in moths. European Comparative Endocrinologists. Meeting in Antwerp, Belgium -6/1/04 - 4/1/04

Interpretive Summary:

Technical Abstract: The role of ACE (angiotensin converting enzyme) in metamorphic- and reproductive-related events in the cotton leafworm Spodoptera littoralis (Lepidoptera) was studied by use of the selective ACE-inhibitor captopril. After testing different developmental stages, it was clear that captopril was detrimental to adult formation and oviposition. A dose of 50 µg decreased adult formation by 62% and oviposition by 33%. Ecdysteroid titers were measured in the treated stages and compared to controls. While there was no effect in larvae and pupae, the ecdysteroid titer in captopril-treated females was only 45±12 pg/mg BW, whereas the titer was 276±100 pg/mg in controls. Also of importance, treatment with captopril doubled the trypsin activity in female moths. In conclusion, our results suggest that captopril down-regulates oviposition by two independent pathways, one through ecdysteroid biosynthesis regulation, and the other through regulation of trypsin activity. Apparently, oviposition in Lepidoptera is influenced by a complex interaction of ACE, trypsin activity and ecdysteroid biosynthesis. Our results reveal an additional physiological role for ACE.