| 1. |
- Akagi, Nana, et al.
(author)
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Effect of acute endolymphatic hydrops overload on the endolymphatic sac
- 2008
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In: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 128:3, s. 239-44
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Journal article (peer-reviewed)abstract
- CONCLUSIONS: Homeostasis of endolymph volume is a complex mechanism, in which the endolymphatic sac (ES) may play an important role. OBJECTIVES: To elucidate the effect of acute endolymphatic hydrops (EH) on the ES and to gain further information about the volume and pressure regulative function of the ES. MATERIALS AND METHODS: Distilled water was injected into the middle ear cavity of adult CBA/J mice. The ESs were studied morphologically by light and transmission electron microscopy. RESULTS: Mild EH was found, particularly in the upper turn of the cochlea. Acute EH led to an increase in the size of the ES lumen, accompanied by collapse of the lateral intercellular spaces and dense perisaccular tissue, changes which had reversed 2 h after the injection.
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| 2. |
- Akagi, Nana, et al.
(author)
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Effect of inner ear blood flow changes on the endolymphatic sac
- 2008
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In: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 128:11, s. 1187-95
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Journal article (peer-reviewed)abstract
- CONCLUSIONS: That the endolymphatic sac (ES) reacts to changes in inner ear blood flow may be important for homeostasis of the inner ear fluid volume and pressure. OBJECTIVES: To elucidate the effect of changes in inner ear blood flow on the ES and to learn more about the volume and pressure regulatory function of the ES. MATERIALS AND METHODS: Epinephrine or sodium nitroprusside (SNP) was injected into the middle ear cavity of adult CBA/J mice. The ES were analyzed morphologically by light microscopy. RESULTS: Epinephrine reduced the luminal size of the ES leading to an accumulation of intraluminal homogeneous substance. Injection of SNP increased the size of the ES lumen, accompanied by a collapse of the lateral intercellular space (LIS) and dense perisaccular tissue. These changes were almost reversed 4 h after injection.
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| 3. |
- Anniko, Matti
(author)
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Acta Oto-Laryngologica
- 2018
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In: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 138:3, s. 192-193
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Journal article (other academic/artistic)
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| 4. |
- Anniko, Matti, et al.
(author)
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Alpha-Bungarotoxin Inhibits Outer Hair Cell Motility in situ
- 1995
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In: Journal for Oto-Rhino-Laryngology. - : S. Karger AG. - 0301-1569 .- 1423-0275. ; 57:2, s. 105-109
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Journal article (peer-reviewed)abstract
- The effect of two substances (alpha-bungarotoxin, alpha-BGTX, a small protein, and the local anesthetic bupivacaine hydrochloride) with an assumed effect on outer hair cell (OHC) motility were analyzed after exposing the cochlea via the round window membrane. Electrophysiological measurements were performed with a very narrow frequency-specific gating (+/- 100 Hz) technique to determine auditory brainstem response (ABR) thresholds, including ABR-based frequency tuning curves. Exposure to alpha-BGTX gave a minor improvement in thresholds, interpreted as a facilitation of OHCs, i.e. releasing their efferent inhibitory control, whereas exposure to bupivacaine hydrochloride impaired ABR thresholds, possibly due to immobilization of OHC motility via the lateral cell membrane. Our results are consistent with the hypothesis that efferent influence on the cochlea may be linked with a modulation of the mechanical function of OHCs. We can now postulate that there is in vivo evidence that acetylcholine exerts its effect at the OHCs via an alpha-BGTX alpha-BGTX binding acetylcholine receptor.
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| 5. |
- Anniko, Matti, et al.
(author)
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Cytoskeletal basis for contractility of outer hair cells in the normal adult human organ of Corti : Comparisons with vestibular hair cells
- 1995
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In: Journal for Oto-Rhino-Laryngology. - 0301-1569 .- 1423-0275. ; 57:2, s. 61-7
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Journal article (peer-reviewed)abstract
- The present study is the first consecutive analysis of the adult normal human organ of Corti and vestibular hair cells with regard to the expression of F-actin, actin-associated proteins (alpha-actinin, alpha- and beta-spectrins, vinculin and tropomyosin), beta-tubulin and the calcium-binding protein synaptophysin. The expression of these cytoskeletal and their associated proteins in man is largely similar to, although not identical with, that previously described for several other mammalian species. However, a few very unusual staining patterns were found. In several long outer hair cells a rod of F-actin extended from the infracuticular area to the cell nucleus. Fluorescence for tropomyosin occurred both in the cuticular plates of the outer and inner hair cells, and in the area of close apposition between the base of the outer hair cell and the apical part of Deiter's cell. In contrast, the vestibular hair cells showed immunoreactivity for tropomyosin only in the cuticular plates.
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| 6. |
- Anniko, Matti, et al.
(author)
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Cytoskeletal proteins in human hair cells
- 1995
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In: Acta oto-laryngologica. Supplementum. - 0365-5237 .- 1651-2464. ; 519, s. 8-12
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Journal article (peer-reviewed)abstract
- Human cochlear and vestibular hair cells (HCs) were analysed for the three major cytoskeletal types of structures: microfilaments, microtubules, and intermediate filaments and several of their associated proteins. Specific immunomorphological features were identified: the apical surface, the infracuticular rod of F-actin, the cytoplasm and the HC bases and their interactions with adjacent supporting cells. There is morphological evidence for at least three functionally interacting units: the OHC as a cytoskeletal string interacting with the Deiter's cell, being a part of the rigid pancellular protein shell of the organ of Corti; compartmentalization of HCs (surrounded by rigid intermediate filament proteins in the supporting cells); and a calcium-guided short-loop feed-back control of type I HCs. The cytoskeletal composition of all four types of human HCs and their adjacent structures is similar to, although not identical with, corresponding compositions in other mammalian species.
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| 7. |
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| 8. |
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| 9. |
- Anniko, Matti, et al.
(author)
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Hyaluronic acid as a molecular filter and friction reducing lubricant in the human inner ear
- 1995
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In: Journal for Oto-Rhino-Laryngology. - 0301-1569 .- 1423-0275. ; 57:2, s. 82-6
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Journal article (peer-reviewed)abstract
- Immunofluorescence for hyaluronic acid occurred intracellularly in morphologically highly specialized areas in the adult human inner ear, for instance in the cuticular plates of all types of hair cells, at the apposition between outer hair cells and Deiter's cell bodies and in the near-surface area of Hensen's cells. The cytoskeletal organization in these regions is characterized by tightly packed filamentous proteins. Under physiological stimulus these regions undergo micromechanical change, either actively moving (force generation) or passively vibrating with changes in elasticity. Hyaluronic acid might therefore act as a friction-reducing molecular lubricant. In the lateral wall of the cochlea an accumulation of hyaluronic acid occurred in the loose connective tissue of the spiral ligament, in particular close to the stria vascularis. Due to its complex molecular network, hyaluronic acid offers considerable resistance to bulk flow of water and may exclude molecules. The basal cell region of the stria vascularis is thus given additional support to minimize (seal?) the stria vascularis towards all other areas except the endolymphatic space. Here, hyaluronic acid could act as a molecular filter.
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| 10. |
- Anniko, Matti, et al.
(author)
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Microtubule-associated proteins in adult human sensory organs
- 1995
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In: Journal for Oto-Rhino-Laryngology. - 0301-1569 .- 1423-0275. ; 57:2, s. 78-81
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Journal article (peer-reviewed)abstract
- The distribution of microtubule-associated proteins MAP-1 and MAP-2 was analysed with immunomorphological techniques in the serially sectioned adult human membranous labyrinth. In the organ of Corti, monoclonal antibodies to MAP-1 did not stain. Positivity for MAP-2 occurred in the entire outer hair cell cytoplasm, in the inner hair cells (?), in the nerve fibres and in the cytoplasm of epithelial cells of the spiral prominence. In addition, staining for MAP-2 was identified in many (but not all) cells or Reissner's membrane. Immunofluorescence for MAP-1 occurred in the supporting cells of the cristae and maculae interpreted to be localized in the apical region adjacent to the sensory cells. Thus, the distribution of MAP-1 and MAP-2 in the adult human membranous labyrinth was the same as described for several animal species with regard to the cochlea. In contrast to such a pattern, both MAP-1 and MAP-2 were identified in the human vestibular organs, thus identifying a subpopulation of centrally located nerve calyces and possibly also the apical portion of vestibular hair cells.
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