scholarly journals Developmental abnormalities of the otic capsule and inner ear following application of prolyl-hydroxylase inhibitors in chick embryos

2018 ◽  
Vol 110 (15) ◽  
pp. 1194-1204
Author(s):  
Akshay Kumar ◽  
Thomas G. Davies ◽  
Nobue Itasaki
Keyword(s):  
Inner Ear ◽  
Prolyl Hydroxylase ◽  
Otic Capsule ◽  
Chick Embryos ◽  
Developmental Abnormalities

scholarly journals Effect of cortisol acetate on collagen biosynthesis and on the activities of prolyl hydroxylase, lysyl hydroxylase, collagen galactosyltransferase and collagen glucosyltransferase in chick-embryo tendon cells

1977 ◽  
Vol 164 (3) ◽  
pp. 533-539 ◽  
Author(s):  
A Oikarinen
Keyword(s):  
Chick Embryo ◽  
Enzyme Activities ◽  
Collagen Synthesis ◽  
Enzyme Synthesis ◽  
Prolyl Hydroxylase ◽  
Chick Embryos ◽  
Isolated Cells ◽  
Lysyl Hydroxylase ◽  
Tendon Cells

Collagen synthesis and the activities of prolyl hydroxylase, lysyl hydroxylase, collagen galactosyltransferase and collagen glucosyltransferase were studied in isolated chick-embryo tendon cells after the administration of cortisol acetate to the chick embryos. When the steroid was injected 1 day before isolation of the tendon cells, collagen synthesis was decreased, even though the enzyme activities were not changed. When cortisol acetate was given as repeated injections over a period of 4 days, both collagen synthesis and the enzyme activities decreased. The hydroxylase activities decreased even more than the two collagen glycosyltransferase activities, both in isolated cells and in whole chick embryos. The amount of prolyl hydroxylase protein diminished to the same extent as the enzyme activity, indicating that cortisol acetate inhibits enzyme synthesis. The inhibitory effect of cortisol acetate on collagen synthesis and on the enzyme activities was partially reversible in 3 days. Total protein synthesis was completely restored within this time. Only massive doses of cortisol acetate inhibited collagen synthesis in vitro. Additional experiments indicated that cortisol acetate did not decrease the rate of the enzyme reactions when added directly to the enzyme incubation mixtures. The results suggest that cortisol acetate decreases collagen synthesis both by its direct effect on collagen polypeptide-chain synthesis and by decreasing the activities of enzymes involved in post-translational modifications.

Hyaluronate production by the inner ear during otic capsule and perilymphatic space formation

1987 ◽  
Vol 8 (5) ◽  
pp. 265-272 ◽  
Author(s):  
Joseph R. McPhee ◽  
Thomas R. Van De Water ◽  
Hung-Xi Su
Keyword(s):  
Inner Ear ◽  
Otic Capsule ◽  
Perilymphatic Space

X-ray microtomography study of otic capsule deficiencies: three-dimensional modelling of the fissula ante fenestram

2015 ◽  
Vol 129 (9) ◽  
pp. 840-851 ◽  
Author(s):  
J W Lee ◽  
P Sale ◽  
N P Patel
Keyword(s):  
Inner Ear ◽  
Three Dimensional ◽  
Oval Window ◽  
Otic Capsule ◽  
X Ray ◽  
Otologic Surgery ◽  
Science Group ◽  
Temporal Bones ◽  
The Relationship ◽  
Non Destructive

AbstractBackground:The postulated sites of perilymph fistulae involve otic capsule deficiencies, in particular, at the fissula ante fenestram. Histological studies have revealed this to be a channel extending from the middle ear, and becoming continuous with the inner ear medial to the anterior limit of the oval window. The relationship between a patent fissula and symptoms of perilymph fistula is contentious.Objective:The understanding of the anatomy of the fissula ante fenestram is incomplete. Histopathology is inherently destructive to the delicate ultrastructure of the middle and inner ear. Conversely, X-ray microtomography allows non-destructive examination of the otic capsule. In this study, we used X-ray microtomography to characterise the fissula ante fenestram.Materials and methods:We imaged cadaveric temporal bones with X-ray microtomography. We used the Avizo Fire (Visualization Science Group, Merignac Cedex, France) software to perform post-processing and image analysis.Results:Three-dimensional modelling of the fissula ante fenestram allowed stratification into four forms: rudimentary pit; partial fissula; complete occluded fissula; and complete patent fissula.Conclusion:X-ray microtomography showed that the fissula ante fenestram is present in various forms from rudimentary pit to complete deficiency of the otic capsule. This understanding may have implications for otologic surgery and clinical diagnosis of perilymph fistula.

scholarly journals Sonic Hedgehog Regulates Otic Capsule Chondrogenesis and Inner Ear Development in the Mouse Embryo

2002 ◽  
Vol 248 (2) ◽  
pp. 240-250 ◽  
Author(s):  
W. Liu ◽  
G. Li ◽  
J.S. Chien ◽  
S. Raft ◽  
H. Zhang ◽  
...  
Keyword(s):  
Inner Ear ◽  
Sonic Hedgehog ◽  
Mouse Embryo ◽  
Otic Capsule ◽  
Ear Development ◽  
Inner Ear Development
Sign in / Sign up

Export Citation Format

Share Document