“In aquatic vertebrates, the Octavolateralis efferent (OLe) system provides efferent innervation to hair cells of the lateral line and ear, whereas in terrestrial vertebrates only the ear is innervated. OLe neurons are considered to be a subset of cranial motor neurons that innervate neuroepithelium rather than muscle. The lateral line, which is unique to aquatic vertebrates, is a sensory system mainly responsible for detection of water displacement (Coombs et al., 1989). The lateral line nerve as well as the vestibuloacoustic nerve terminates at hair cells that are innervated by both sensory and efferent (octavolateralis efferent, OLe) nerves (Roberts and Meredith, 1989; 1992; Highstein, 1991). The facial motor (nVII) and OLe neurons are located in close proximity, and the efferent axons from both cell types extend together in the hindbrain. “Higashima et al., 2000).
The statoacoustic ganglion is the sensory ganglion of the ear. Neurons of this ganglion innervate hair cells of the sensory placodes of the inner ear, their central processes form the VIIIth (octaval) nerve. The statoacoustic ganglion is formed by cells that delaminate from the otic placode. These neuroblasts undergo an epithelial to mesenchymal transistion to leave the otic vesicle. they congregate beneath the rosatral part of the otic vesicle and differentiate into the neruons pf the VIIIth ganglion (Whitfield et al., 2002). Fibers of the octaval nerve (nVIII) innervate three separate clusters of hair cells within the ear (Raible & Kruse, 2000).
Large and small acetylcholine transferase(ChAT) positive somata belonging to the midline octavolateralis efferent system. Some ChAT positive fibres are also present in the medial octavolateralis nucleus indicating that this nucleus forms part of the cholinergic system in the zebrafish (Mueller et al., 2004).
The medial octavolateralis nucleus, along with the rest of the lateral line system, receives dopaminergic input from the A11 homolog groups in the anterior part of the posterior tuberculum (Haehnel-Taguchi et al., 2018).
Key Publications
Shin-ichi Higashijima, Yoshiki Hotta, and Hitoshi Okamoto
Visualization of Cranial Motor Neurons in Live Transgenic Zebrafish Expressing Green Fluorescent Protein Under the Control of the Islet-1 Promoter/Enhancer.
The Journal of Neuroscience, January 1, 2000, 20(1):206–218
Arminda Suli, Nathan Mortimer, Iain Shepherd, and Chi-Bin Chien
Netrin/DCC Signaling Controls Contralateral Dendrites of Octavolateralis Efferent Neurons
The Journal of Neuroscience, December 20, 2006 • 26(51):13328 –13337
Thomas Mueller, Philippe Vernier, Mario F. Wullimann
The adult central nervous cholinergic system of a neurogenetic model animal, the zebrafish Danio rerio
Brain Research 1011 (2004) 156–169
Melanie Haehnel-Taguchi, António M. Fernandes, Margit Böhler, Ina Schmitt, LenaTittel1 and WolfgangDriever
Projections of the Diencephalospinal Dopaminergic System to Peripheral Sense Organs in Larval Zebrafish (Danio rerio)
Front. Neuroanat., 19 March 2018 | https://doi.org/10.3389/fnana.2018.00020
TANYA T. WHITFIELD, BRUCE B. RILEY, MING-YUNG CHIANG, AND BRYAN PHILLIPS
Development of the Zebrafish Inner Ear
DEVELOPMENTAL DYNAMICS 223:427–458 (2002)
DAVID W. RAIBLE AND GREGORY J. KRUSE
Organization of the Lateral Line System in Embryonic Zebrafish
THE JOURNAL OF COMPARATIVE NEUROLOGY 421:189–198 (2000)