RESTRICTED OCCURRENCE OF LOCUSTA-MIGRATORIA OVARY MATURING PARSIN IN THE BRAIN-CORPORA CARDIACA COMPLEX OF VARIOUS INSECT SPECIES

Ovary maturing parsin (OMP) is a gonadotrophic molecule previously iso lated from the neurosecretory lobes of the corpora cardiaca of Locusta Migratoria (acridian Orthoptera). A polyclonal antiserum directed aga inst the two biologically active domains of the L. migratoria (Lom) OM P was used to investigate the occurrence of Lom OMP-like substances in brain-corpora cardiaca complexes of other insect species. Using immun ohistochemistry, specimens of 40 different insect species belonging to 13 insect orders were tested. The Lom OMP-like substance was strictly limited to specimens of insect species belonging to the Acridae. It o ccurred in non-basophilic cells of the pars intercerebralis that proje ct to the corpora cardiaca, as in Locusta. Although the antiserum only detected Lom OMP-like material in the Acridae, it is possible that re lated molecules exist in other insects. The antiserum may be very spec ific for domains of the Lom OMP molecule that have not been highly con served during evolution or possibly these domains are not accessible t o the antiserum in other insects.