Several forms of callitachykinins are distributed in the central nervous system and intestine of the blowfly Calliphora vomitoria.
We have examined the distribution of two tachykinin-related neuropeptides, callitachykinin I and II (CavTK-I and CavTK-II), isolated from whole-animal extracts of the blowfly Calliphora vomitoria. Extracts of dissected brains, thoracic-abdominal ganglia and midguts of adult blowflies and the entire central nervous system of larval flies were analysed by high performance liquid chromatography (HPLC) combined with enzyme-linked immunosorbent assay (ELISA) for the presence of CavTKs. To identify the two neuropeptides by HPLC, we used the retention times of synthetic CavTK-I and II as reference and detection with an antiserum raised to locustatachykinin II (shown here to recognise both CavTK-I and II). The brain contains only two immunoreactive components, and these have exactly the same retention times as CavTK-I and II. The thoracic-abdominal ganglia and midgut contain immunoreactive material eluting like CavTK-I and II as well as additional material eluting later. The larval central nervous system (CNS) contains material eluting like CavTK-I and II as well as a component that elutes earlier. We conclude that CavTK-I and II are present in all assayed tissues and that additional, hitherto uncharacterised, forms of tachykinin-immunoreactive material may be present in the body ganglia and midgut as well as in the larval CNS. An antiserum was raised to CavTK-II for immunocytochemistry. This antiserum, which was found to be specific for CavTK-II in ELISA, labelled all the neurones and midgut endocrine cells previously shown to react with the less selective locustatachykinin antisera. It is not clear, however, whether CavTK-I and II are colocalised in all LomTK-immunoreactive cells since there is no unambiguous probe for CavTK-I.
Nässel
D R
DR
Department of Zoology, Stockholm University, Sweden.
Kim
M Y
MY
Lundquist
C T
CT
D000595:Amino Acid Sequence; D000818:Animals; D002490:Central Nervous System / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D004175:Diptera / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000378:metabolism; D008969:Molecular Sequence Data; D015320:Tachykinins / Q000032:analysis*
D015320:Tachykinins; C090692:callitachykinin I