NGIWYamide-induced contraction of tube feet and distribution of NGIWYamide-like immunoreactivity in nerves of the starfish Asterina pectinifera.
NGIWYamide, a neuropeptide recently isolated from sea cucumbers, was tested on tube feet of the starfish Asterina pectinifera. NGIWYamide (10(-6)-10(-4) M) caused contraction of isolated tube feet. NGIWYamide-like immunoreactivity (NGIWYa-LI) was investigated with an antiserum against NGIWYamide. NGIWYa-LI was found in the radial nerve cord (RNC), the marginal nerve, and the tube feet. Both ectoneural and hyponeural parts of the RNC showed NGIWYa-LI. Immunoreactive cell bodies were found in both parts of RNC. Extensive labeling in the basal region of the ectoneural part suggests that a substantial proportion of axons in this part contains NGIWYamide or a similar substance. In tube feet, NGIWYa-LI was found in the sub-epithelial nerve plexus and in the basal nerve ring. Double labeling along with 1E11, a neuron-specific monoclonal antibody developed from A. pectinifera, indicated that the structures with NGIWYa-LI are neurons. These results suggest that NGIWYamide or an NGIWYamide-like peptide exists in starfish and functions as a neurotransmitter or a neuromodulator.
Saha
Apurba Kumar
AK
Department of Biological Sciences, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, O-okayama, Tokyo, Japan. apurbaksaha@yahoo.com
Tamori
Masaki
M
Inoue
Masahide
M
Nakajima
Yoko
Y
Motokawa
Tatsuo
T
D000818:Animals; D047288:Asterina / Q000378:metabolism / Q000502:physiology*; D017952:Ganglia, Invertebrate / Q000502:physiology*; D007150:Immunohistochemistry / Q000662:veterinary; D008124:Locomotion / Q000502:physiology*; D009479:Neuropeptides / Q000378:metabolism / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000378:metabolism / Q000502:physiology
D009479:Neuropeptides; D018377:Neurotransmitter Agents; C113892:asparaginyl-glycyl-isoleucyl-tryptophyl-tyrosinamide