Ultrastructural localization of RFamide-like peptides in neuronal dense-cored vesicles in the peduncle of Hydra.

Abstract

The presence of Arg-Phe-amide (RFamide)-like peptides in dense-cored vesicles in neurons of the peduncle of Hydra was demonstrated by immunogold electron microscopy. Thin sections of Lowicryl-embedded tissue labeled with antisera to RFamide and 5-nm gold-conjugated, secondary antibody and of Epon-Araldite-embedded tissue labeled with 15-nm gold particles revealed a concentration of RFamide-like immunoreactivity over the granular cores of vesicles in epidermal ganglion cells. Gold-labeled, dense-cored vesicles were present in the perikaryon, long thin neurites, and axon terminals of these neurons. The aggregation of labeled dense-cored vesicles in an axon terminal on the myoneme of an epitheliomuscular cell suggests a possible function of RFamide-like peptides in neuromuscular transmission. Gold staining of dense-cored vesicles completely disappeared when the RFamide antiserum was preabsorbed with 10 micrograms/ml RFamide. These results are the first demonstration that the dense-cored vesicles of Hydra neurons contain a neuropeptide.

• Authors: O Koizumi, J D Wilson, C J Grimmelikhuijzen, J A Westfall
• Journal: The Journal of experimental zoology (J Exp Zool) Vol. 249 Issue 1 Pg. 17-22 (Jan 1989) ISSN: 0022-104X [Print] United States
• PMID: 2926357 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Neuropeptides

Topics

• Animals
• Hydra (analysis, ultrastructure)
• Immunohistochemistry
• Microscopy, Electron
• Neuropeptides (analysis)