The association of crustacean cardioactive peptide with the spermatheca of the African migratory locust, Locusta migratoria.

Abstract

Crustacean cardioactive peptide (CCAP)-like immunoreactivity was identified in neurons of the VIIIth abdominal ganglion and in axons in the nerves that project to the spermatheca of 3-4 week old adult female locusts. In addition, lightly stained CCAP-like immunoreactive processes were localized over the spermathecae. The amount of CCAP in the spermathecal tissue was quantified using an enzyme-linked immunosorbent assay (ELISA) performed on extracts of the whole spermatheca, and on its constituent parts, namely the sperm sac, coiled duct and straight duct. The spermatheca contains 920+/-273 fmol (mean+/-SE) of CCAP equivalents, with the majority localized in the coiled duct. There are age-related differences in the amount of CCAP present in the spermathecae with less content in spermathecae from 1 to 5 day old and greater content in spermathecae from 3 to 4 week old adults. There was also no difference in CCAP content of spermathecae in mated and virgin 3 to 4 week old adults. Reversed phase-high performance liquid chromatography (RP-HPLC) followed by ELISA further confirmed the presence of CCAP-like material in extracts of locust spermathecae. Physiological assays demonstrated that CCAP increased the basal tonus and frequency of spontaneous contractions of the spermatheca, with thresholds between 10(-10) and 10(-9)M and maxima at 10(-7)M CCAP. CCAP also increases the amplitude of neurally evoked contractions with a threshold less than 10(-11)M and a maximum of 10(-7)M CCAP. The present study suggests that CCAP acts as a neuromodulator/neurotransmitter at the spermathecal visceral tissue of female Locusta migratoria.

• Authors: Rosa da Silva, Angela B Lange
• Journal: Journal of insect physiology (J Insect Physiol) Vol. 52 Issue 4 Pg. 399-409 (Apr 2006) ISSN: 0022-1910 [Print] England
• PMID: 16516227 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Neuropeptides
• Neurotransmitter Agents
• crustacean cardioactive peptide

Topics

• Animals
• Enzyme-Linked Immunosorbent Assay
• Female
• Genitalia, Female (innervation, metabolism)
• Immunohistochemistry
• Locusta migratoria (metabolism)
• Muscle Contraction (physiology)
• Neuropeptides (metabolism, physiology)
• Neurotransmitter Agents (metabolism)