Abstract
Triazene administration to 10-day pregnant mice gave rise to severe ear abnormalities, including middle ear ossicle malformations. The head of the malleus and the body of the incus were sometimes absent. In some instances, the stapes appeared dysplastic. The stapedial artery was often quite dilated, as well as other cephalic vessels, but qualitatively normal. Severe inner ear abnormalities were observed, as well as auditory nerve disruption, which was associated with central nervous system lesions. Multiple haematomas were present in the embryonic face, but ear abnormalities occurred even in the absence of local hemorhages. We postulate a direct effect of the teratogen on the branchial mesenchyme. This model seems to be useful for the comprehension of human middle ear abnormalities, but does not constitute a phenocopy of hemicranial microsomia.
Résumé
L'administration de triazène à des souris gestantes au 10ème jour donne lieu à de sévères anomalies de l'oreille, incluant des malformations des osselets du cavum tympanique. La tête du malleus et le corps de l'incus sont souvent absents. Dans un certain nombre de cas, le stapes apparaît anormal. Dans la majorité de cas, l'a, stapédienne, qualitativement normale, apparaît dilatée au même titre que la plupart des autres vaisseaux céphaliques. De sévères anomalies de l'oreille interne sont observées, ainsi que des ruptures du n. vestibulo-cochléaire associées à d'importantes lésions du système nerveux central. De multiples hématomes sont présents dans la face, mais les malformations de l'oreille peuvent apparaître en l'absence des hémorragies. Nous pensons que l'agent tératogène exerce un effet direct sur le mésenchyme branchial. Ce modèle apparaît utile pour la compréhension des anomalies de l'oreille rencontrées dans l'espèce humaine, mais ne constitue nullement un modèle de la microsomie hémicrâniofaciale.
Similar content being viewed by others
References
Burk D, Sadler TW (1983) Morphogenesis of median facial clefts in mice treated with diazo-oxo-norleucine (DON). Teratol 27: 385–394
Darab DJ, Minkoff R, Sciote J, Sulik KK (1976) Pathogenesis of median facial clefts in mice treated with methothrexate. Teratol 36: 77–86
Hanson JR, Anson BJ, Strickland EM (1963) Branchial sources of the auditory ossicles in man. Part II. Observation of embryonic stages from 7 mm to 28 mm (CR length). Arch Otolaryngol 76: 200–215.
Kaufman MH (1992) An atlas of mouse development. Academic Press, London
Lasjaunias P, Berenstein A (1987) Surgical neuroangiography. 1. Functional anatomy of the craniofacial arteries. Springer, Berlin
Louryan S (1986) Morphogenèse des osselets de l'oreille moyenne chez l'embryon de souris. I. Aspects morphologiques. Arch Biol 97: 317–337
Louryan S (1991)In vitro development of mouse middle ear ossicles: a preliminary report. Eur Arch Biol 102: 55–58
Louryan S (1993) Le développement des osselets de l'ouïe chez l'embryon humain: corrélations avec les données recueillies chez la souris. Bull Assoc Anat 77: 29–32
Louryan S, Glineur R, Dourov N (1992) Induced and genetic mouse middle ear ossicles malformations: a model to human malformative ossicular disease and a tool for clarifying their normal ontogenesis. Surg Radiol Anat 14: 227–232
Louryan S, Glineur R (1992) The mouse stapes develops mainly from the Reichert's cartilage independently of the otic capsule. Eur Arch Biol 103: 211–212
Louryan S, Goffard JC, Milaire J (1994) Teratogenic effects of methyl triazene in NMRI mouse embryos: preliminary observations. Eur Arch Biol 104: 157–165
Milunsky A, Graef JW, Gaynor MF Jr (1968) Methotrexate-induced congenital malformations. J Pediatr 72: 790–795
Poswillo D (1973) The pathogenesis of the first and second branchial arch syndrome. Oral Surg 35: 302–328
Sulik KK, Johnston MC, Smiley SJ, Speight HS, Jarvis BE (1987) Mandibulofacial dysostosis (Treacher Collins syndrome): a new proposal for its pathogenesis. Am J Med Gen 27: 359–372
Sulik KK, Cook CS, Webster WS (1988) Teratogens and craniofacial malformations: relationships to cell death. Development 103 [Suppl]: 213–232
Warkany J (1978) Aminopterin and methotrexate: folic acid deficiency. Teratol 17: 353–358
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Louryan, S., Heymans, O. & Goffard, JC. Ear malformations in the mouse embryo following maternal administration of triazene, with clinical implications. Surg Radiol Anat 17, 59–63 (1995). https://doi.org/10.1007/BF01629502
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01629502