Morphological Distribution Patterns and Neuroimmune Communication of Ganglia in Molly Fish (Poecilia sphenops, Valenciennes 1846)

• Published in: Fishes Vol. 8; no. 6; p. 289
• Main Authors: Mokhtar, Doaa M, Attaai, Abdelraheim, Zaccone, Giacomo, Alesci, Alessio, Alonaizan, Rasha, Hussein, Manal T
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-05-2023
• Subjects: Acetylcholine; Autonomic nervous system; Axons; CD3 antigen; CD68; Cell interactions; Communication; Dendritic cells; Distribution; Distribution patterns; Dorsal root ganglia; Electron microscopy; Ethanol; Fibers; Fish; Ganglia; Ganglion cells; ganglionic neurons; GFAP; Gills; Glial cells; Glial fibrillary acidic protein; Head; Iba1; Immunoreactivity; Kidneys; Lymphocytes; Lymphocytes T; Macrophages; Microscopy; Nerves; Nervous system; Neuronal-glial interactions; Neurons; Neuropeptides; Neurotransmitters; Oligodendrocytes; Physiological aspects; Physiology; Poecilia sphenops; Poeciliidae; Proteins; Satellite cells; Sensory neurons; Spinal cord; Vestibular system; Egypt; United States > US
• ISSN: 2410-3888; 2410-3888
• DOI: 10.3390/fishes8060289

Twenty-four adult molly fish (Poecilia sphenops, Valenciennes 1846) were collected to study the morphology and distribution of ganglia using histological, immunohistochemical, and electron microscopy and focusing on their relation to the immune cells. The ganglia were classified spatially into cranial and spinal, and functionally into sensory and autonomic. Spinal ganglia (dorsal root ganglia, DRG) contained large close ganglionic cells, enclosed by satellite cells, as well as bundles of both myelinated and non-myelinated nerve fibers. There are glial cells, immune cells and telocytes close to the ganglion. In addition, oligodendrocytes were closely related to myelinated axons. Glial fibrillary acidic protein (GFAP) expression was confined to the glia cells and the nerve fibers in the cervical ganglia next to the gills, and surprisingly, in the large ganglionic cells of the DRG. The vestibular ganglia were large, connected to the hind brain, and contained numerous neurons packed in columns. The cervical ganglia were large and observed around the pseudobranch, head kidney, and thymus. Their neurons are randomly distributed, and nerve fibers are peripherally situated. CD3-positive T-lymphocytes, dendritic cells, and CD68-positive macrophages were in close contact with the ganglia. Furthermore, the ganglia around the head kidney showed positive Iba1-expressing cells. Most ganglion cells and nerve fibers in the DRG, autonomic, and vestibular ganglia showed moderate to strong S-100 immunoreactivity. The enteric glia, CD68-expressing macrophages, and acetylcholine (Ach)-expressing neurons were observed along the muscular layer of the intestinal wall. In conclusion, different ganglia of molly fish displayed direct communication with immune cells which support and maintain healthy ganglionic cells.