Isolation and immunochemical characterization of neuropeptides from the midgut of the Colorado potato beetle Leptinotarsa decemlineata

The midgut of the Colorado potato beetle showed endocrine cells immunopositive to monoclonals like MAC-18, MAC-3 and polyclonals to FMRFamide and AKH-241. Extraction and HPLC-fractionation of the midgut extracts after partial purification and characterization showed immunopositive reaction to the monoclonals and also showed myotropic activity stimulating the potato beetle gut. Molecular mass of the two active peptides isolated were 22 and 26 kDa respectively. Both these peptides could be immunocytochemically demonstrated in the brain neurosecretory cells of the red cotton bug, Dysdercus cingulatus and the castor semilooper, Achaea janata as well.