FMRFamide-expressing efferent neurons in eighth abdominal ganglion innervate hindgut in the silkworm, Bombyx mori.

Abstract

The tetrapeptide FMRFamide is known to affect both neural function and gut contraction in a wide variety of invertebrates and vertebrates, including insect species. This study aimed to find a pattern of innervation of specific FMRFamide-labeled neurons from the abdominal ganglia to the hindgut of the silkworm Bombyx mori using the immunocytochemical method. In the 1st to the 7th abdominal ganglia, labeled efferent neurons that would innervate the hindgut could not be found. However, in the 8th abdominal ganglion, three pairs of labeled specific efferent neurons projected axons into the central neuropil to eventually innervate the hindgut. Both axons of two pairs of labeled cell bodies in the lateral rind and axons of one pair of labeled cell bodies in the posterior rind extended to the central neuropil and formed contralateral tracts of a labeled neural tract with a semi-circular shape. These labeled axons ran out to one pair of bilateral cercal nerves that extended out from the posterior end of the 8th abdominal ganglion and finally to the innervated hindgut. These results provide valuable information for detecting the novel function of FMRFamide-related peptides in metamorphic insect species.

• Authors: So Young Na, Dong Kyung Sung, Ka Kyung Kim, Kang Min Kim, Jin Hee Kim, Hun Hee Park, Sang Mong Lee, Su Il Seong, Jong-Soo Chang, Jae Sam Hwang, Seok Woo Kang, Hak Ryul Kim, Bong Hee Lee
• Journal: Zoological science (Zoolog Sci) Vol. 21 Issue 8 Pg. 805-11 (Aug 2004) ISSN: 0289-0003 [Print] Japan
• PMID: 15333991 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• FMRFamide

Topics

• Animals
• Bombyx (anatomy & histology, metabolism)
• Digestive System (innervation)
• FMRFamide (metabolism)
• Ganglia, Invertebrate (metabolism)
• Immunohistochemistry
• Neurons, Efferent (metabolism)