Identification of cells expressing Calcitonins A and B, PDF and ACP in Locusta migratoria using cross-reacting antisera and in situ hybridization

Peptides. 2021 Dec:146:170667. doi: 10.1016/j.peptides.2021.170667. Epub 2021 Sep 29.


This work was initiated because an old publication suggested that electrocoagulation of four paraldehyde fuchsin positive cells in the brain of Locusta migratoria might produce a diuretic hormone, the identity of which remains unknown, since none of the antisera to the various putative Locusta diuretic hormones recognizes these cells. The paraldehyde fuchsin positive staining suggests a peptide with a disulfide bridge and the recently identified Locusta calcitonins have both a disulfide bridge and are structurally similar to calcitonin-like diuretic hormone. In situ hybridization and antisera raised to calcitonin-A and -B were used to show where these peptides are expressed in Locusta. Calcitonin-A is produced by neurons and neuroendocrine cells that were previously shown to be immunoreactive to an antiserum to pigment dispersing factor (PDF). The apparent PDF-immunoreactivity in these neurons and neuroendocrine cells is due to crossreactivity with the calcitonin-A precursor. As confirmed by both an PDF-precursor specific antiserum and in situ hybridisation, those calcitonin-A expressing cells do not express PDF. Calcitonin B is expressed by numerous enteroendocrine cells in the midgut as well as the midgut caeca. A guinea pig antiserum to calcitonin A seemed quite specific as it recognized only the calcitonin A expressing cells. However, rabbit antisera to calcitonin-A and-B both crossreacted with neuroendocrine cells in the brain that produce ACP (AKH/corazonin-related peptide), this is almost certainly due to the common C-terminal dipeptide SPamide that is shared between Locusta calcitonin-A, calcitonin-B and ACP.

Keywords: ACP; Affinity column; Calcitonin A; Calcitonin B; Locust; PDF.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Calcitonin / chemistry
  • Calcitonin / immunology
  • Calcitonin / metabolism*
  • Guinea Pigs
  • Immune Sera
  • In Situ Hybridization
  • Insect Proteins / chemistry
  • Insect Proteins / metabolism*
  • Locusta migratoria / metabolism*
  • Neuropeptides / chemistry
  • Neuropeptides / metabolism*


  • Immune Sera
  • Insect Proteins
  • Neuropeptides
  • Calcitonin