A COMPARATIVE-STUDY OF LEUCOKININ-IMMUNOREACTIVE NEURONS IN INSECTS

Antisera were raised against leucokinin IV, a member of the leucokinin peptide family. Immunohistochemical localization of leucokinin immuno reactivity in the brain of the cockroach Nauphoeta cinerea revealed ne urosecretory cells in the pars intercerebralis and pars lateralis, sev eral bilateral pairs of interneurons in the protocerebrum, and a group of interneurons in the optic lobe. Several immunoreactive interneuron s were found in the thoracic ganglia, while the abdominal ganglia cont ained prominent immunoreactive neurosecretory cells, which projected t o the lateral cardiac nerve. The presence of leucokinins in the abdomi nal nerve cord was confirmed by HPLC combined with ELISA. Leucokinin-i mmunoreactive neurosecretory cells were also found in the pars interce rebralis of the cricket Acheta domesticus and the mosquito Aedes aegyp ti, but not in the locust Schistocerca americana or the honey bee Apis mellifera. However, all these species have leucokinin-immunoreactive neurosecretory cells in the abdominal ganglia. The neurohemal organs i nnervated by abdominal leucokinin-immunoreactive cells were different in each species.