Distribution of thyrotropin-releasing hormone in the rat spinal cord with special reference to sympathetic nuclei: A light- and electron-microscopic immunocytochemical study
| Autor: | P. Poulat, N. Rajaofetra, F. Sandillon, C. Oliver, L. Marlier, Alain Privat |
|---|---|
| Rok vydání: | 1992 |
| Předmět: |
Sympathetic Nervous System
Histology Dendritic spine Central nervous system Thyrotropin-releasing hormone Dendrite Biology medicine Animals Tissue Distribution Thyrotropin-Releasing Hormone Intercalated nucleus General Neuroscience Rats Inbred Strains Cell Biology Anatomy Spinal cord Immunohistochemistry Rats Microscopy Electron medicine.anatomical_structure Spinal Cord Synapses Ultrastructure Nucleus |
| Zdroj: | Journal of Neurocytology. 21:157-170 |
| ISSN: | 1573-7381 0300-4864 |
| DOI: | 10.1007/bf01194975 |
| Popis: | This paper deals with the distribution of thyrotropin-releasing hormone-like immunoreactivity in the spinal cord of the rat, and particularly in the sympathetic nuclei, at light and electron microscopic levels. In the dorsal horn, the inner part of laminae II and III displayed thin thyrotropin-releasing hormone immunoreactive profiles. Electron microscopy revealed small immunoreactive varicosities which made synaptic contact with small dendrites or dendritic spines. Dense thyrotropin-releasing hormone-like immunoreactivity was observed in all sympathetic nuclei (nucleus intermediolateralis pars fascicularis and principalis, nucleus intercalatus and dorsal commissural nucleus) except the nucleus intercalatus pars ependymalis. Electron microscopy showed many immunoreactive varicosities which were often in synaptic contact with dendrites (proximal or distal), rarely with perikarya and never with axons. Sometimes, the same immunoreactive varicosity made axodendritic contacts with two dendrites and, conversely one dendrite was sometimes synaptically contacted by two or more immunoreactive varicosities. The ventral horn displayed a diffuse thyrotropin-releasing hormone-like immunoreactivity except for the cremaster nucleus (at lumbar level) which was densely outlined by immunoreactive profiles. Occasionally a large cell body in lamina IX (a putative motoneuron) was outlined by immunoreactive profiles but ultrastructural studies revealed very few immunoreactive axosomatic synapses, while immunoreactive symmetrical or asymmetrical axodendritic synapses were observed. The present study clearly confirms the existence of thyrotropin-releasing hormone immunoreactive synapses, thus substantiating the physiological role of this hormone in the spinal cord. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink