The association of crustacean cardioactive peptide with the spermatheca of the African migratory locust, Locusta migratoria.
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.
da Silva
Rosa
R
Department of Biology, University of Toronto at Mississauga, 3359 Mississauga Road North, Mississauga, Ont., L5L 1C6 Canada. rose.dasilva@utoronto.ca
Lange
Angela B
AB
D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005836:Genitalia, Female / Q000294:innervation / Q000378:metabolism; D007150:Immunohistochemistry; D048188:Locusta migratoria / Q000378:metabolism*; D009119:Muscle Contraction / Q000502:physiology; D009479:Neuropeptides / Q000378:metabolism* / Q000502:physiology; D018377:Neurotransmitter Agents / Q000378:metabolism
D009479:Neuropeptides; D018377:Neurotransmitter Agents; C058620:crustacean cardioactive peptide