Back to Search
Start Over
Relationship between musculature and nervous system in the regenerating pharynx inGirardia tigrina(Plathelminthes)
- Source :
- Invertebrate Reproduction & Development. 35:109-125
- Publication Year :
- 1999
- Publisher :
- Informa UK Limited, 1999.
-
Abstract
- Summary The study shows that the regenerating pharynx of Girardia tigrina forms a simple and valuable model system for studies of pattern formation in the nervous system and its relationship to the developing muscles. Immunocytochemistry was used, with antisera raised against 5-HT and the native planarian neuropeptide GYIRFamide. We studied the sequential development of the innervation in the regenerating pharynx, and using TRITC-labelled phalloidin we followed the corresponding differentiation and maturation of pharynx musculature. The peptidergic and aminergic neuronal cell types develop according to different time schedules and different modes. Throughout the process, the GYIRFarnide-IR elements are in contact with the old parts of the nervous system, while the apical 5-HT-IR elements develop de novo. In the regenerating pharynx the GYIRFamide-IR nerves develop in a proximodistal direction. The first 5-HT-IR cell bodies appear in the tip of the pharynx and are symmetrically placed. They have no contact to the rest of the nervous system. From these cell bodies processes grow disto-proximally and fasciculate with tibres from the proximal part. A striking parallelism between the appearance of GYIRFamide-IR nerves and muscle fibres stained with TRITC-phalloidin was observed. The GYIRFamide-IR nerves cling to the muscle fibres. These results suggest that the contact between muscle Iibres and GYIRF-IR nerves is essential for the function of pharynx. The delayed appearance of 5-HT-IR nervous elements is discussed in terms of the influence of 5-HT on sprouting of nerve fibres and synapse formation. The development of the pharynx in tail parts after fission is compared with that after pharynx amputation. The faster rate observed for pharynx regenerating after amputation in comparison with that in regenerating tail parts indicates the importance of the remains of the old nervous system in the pharynx structure.
- Subjects :
- Nervous system
Cell type
biology
Phalloidin
Immunocytochemistry
Pharynx
Anatomy
biology.organism_classification
Girardia tigrina
chemistry.chemical_compound
medicine.anatomical_structure
stomatognathic system
chemistry
Planarian
medicine
Animal Science and Zoology
Process (anatomy)
Developmental Biology
Subjects
Details
- ISSN :
- 21570272 and 07924259
- Volume :
- 35
- Database :
- OpenAIRE
- Journal :
- Invertebrate Reproduction & Development
- Accession number :
- edsair.doi...........8cee5cf0277d09948b343da711e735d8
- Full Text :
- https://doi.org/10.1080/07924259.1999.9652375