On the Polarization and Innervation of the Pars Inferior Sensory Epithelia of the Herring Labyrinth

Abstract

Jensen, J . C. 1984. On the polarization and innervation of the pars inferior sensory epithelia of the herring labyrinth. (Zoological Laboratory, University of Aarhus, Denmark.) -Acta 2001. (Stockh.) 65, 61-74.The macula sacculi and the macula lagenae of the herring, Clupea harengus L., were examined by light microscopy. the macula lagenae is large compared ti1 what is normal among non-ostariophysan fishes. the morphological polarization of the hair cells in the inferior maculae shows a pattern which is similar to that usually seer; in teleoit fishes. The fibres in the nerves supplying the macula sacculi and the macula lagenae were counted and their diameters measured. The ramulus saccularis is divided in two separate ramuli innervating populations of hair cells with different morphological polarization. The saccular rostra1 nerve trunk contains 180CL2300 fibres, with 1300-1800 fibres in the caudal nerve trunk. The lagenar nerve is composed of 2100-4000 fibres. The fibre diameters are 1-14 pm in all ramuli. Silver staining of the nerve axoplasm reveals a unique differentiation of the maculae, which can be divided into a central area surrounded by a peripheral part.

Structure and Innervation of the Inner Ear Sensory Organs in an Otophysine Fish, the Upside–down Catfish (Synodontis nigriventrisDavid)

“…His excellent drawing shows that the wide fibres are restricted to one region of the epithelium where they form branched terminations, while the remaining part of the sensory organ is innervated exclusively by thin nerve fibres. Similar observations have been made in the macula sacculi and the macula lagenae in both non-otophysine and otophysine teleosts (Wegner 1982;Saidel & Popper 1983a, 6;Jensen 1984;Mathiesen 1985;Saidel 1988) as well as in the macula utriculi (Mathiesen 1985;Saidel et al 1990a) plus in the anterior and in the horizontal cristae ampullares in nonotophysine fishes (Mathiesen 1985).…”

“…The density of the sensory cells Regional differences in the spatial distribution of the receptor cells within the same sensory organ are found in Synodontis as well as in other teleosts (Dale 1976;Platt 1977;Popper & Hoxter 1984Mathiesen 1985;Yan et al 1991); in addition, a rather great interspecific variation in hair cell density is known among the piscine vertebrates (Dale 1976;Corwin 1977;Platt 1977;Popper 1978;Popper & Northcutt 1983;Jensen 1984;Popper & Hoxter 1984;Mathiesen 1985;Mathiesen & Popper 1987).…”

“…The structure of the otophysine sensory organs has been described only in a few cases (Nakajima & Wang 1974;Jenkins 1977Jenkins , 1979Platt 1977;Popper & Tavolga 1981;Popper & Platt 1983). Quantitative studies of the innervation of the inner ear epithelia in fishes are limited to selected parts of the labyrinth or a single sensory organ (Wegner 1982;Saidel & Popper 1983a, b ;Corwin 1983Corwin , 1985Popper & Northcutt 1983;Jensen 1984;Popper & Hoxter 1984;Mathiesen 1985;Mathiesen & Popper 1987;Sento & Furukawa 1987;Sugihara & Furukawa 1989;Saidel et al 1990a, b ;Popper & Saidel 1990).…”

Sensory Biology of Aquatic Animals

“…Although physiological and neuroanatomical data are not extensive, it has been demonstrated that horizontally and vertically oriented cells on the saccular macula in species other than members of the order Otophysi are innervated hy separate portions of the saccular branch of the eighth nerve Popper 1983a, 1983b;Jensen 1984;Mathiesen 1985). Although physiological and neuroanatomical data are not extensive, it has been demonstrated that horizontally and vertically oriented cells on the saccular macula in species other than members of the order Otophysi are innervated hy separate portions of the saccular branch of the eighth nerve Popper 1983a, 1983b;Jensen 1984;Mathiesen 1985).…”

“…Since innervation studies indicate that individual eighth nerve neurons innervate small areas of the saccular macula Popper 1983a, 1983b;Jensen 1984;Mathiesen 1985), each frequency would maximally stimulate different groups of neurons. One would involve differences in otolith motion (different "motionals") for different frequencies .…”