Localization and Release of FMRFamide-Like Immuno-Reactivity in an Insect Cerebral Neuroendocrine System
Neuropeptides secreted by insect cerebral neurosecretory cells (NSCs) are primary endocrine regulators of physiology, development, and behavior. Recently, many workers have shown that insect NSCs and neurohemal organs are immunoreactive to antisera directed against vertebrate and invertebrate neuropeptides. Thus, the insect homologues of these neuropeptides may serve a neurohormonal function. A possible neuroendocrine role in insects for the tetrapeptide Phe-Met-Arg-Phe-NH2(FMRFamide) (Price and Greenberg, 1977) or analogues thereof was suggested by immunocytochemical staining of neurohemal corpora cardiaca (Boer et al., 1980). Because cerebral NSCs of the moth, Manduca sexta, have been identified (Carrow et al., 1984), we used this model system to further clarify the role of FLI in insects. We briefly describe here the distribution of FMRFamide-like immunoreactivity (FLI) in this cerebral neuroendocrine system and provide evidence for storage and calcium dependent release of FLI from the neurohemal organs (Carroll et al., 1986).
KeywordsCorpus Cardiaca Neurohemal Organ Terminal Ramification Calcium Dependent Release Potassium Depolarization
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