Changes in Corneal Collagen Architecture during Mouse Postnatal Development

Abstract

Changes in corneal thickness before and after eye opening are not caused by widespread alterations in the collagen fibrillar array but are more likely caused by expansion and contraction of regions devoid of regularly arranged collagen. The postnatal development of a corneal annulus of collagen, thought to play a role in stabilizing the curvature of the cornea, may be triggered by visual factors.

From nano to macro: Studying the hierarchical structure of the corneal extracellular matrix

“…This pattern subsequently becomes considerably more pronounced during maturation (Boote et al, 2009). A similar trend was also observed in a WAXS study of mouse postnatal corneal development (Sheppard et al, 2010), in which circumferentially aligned limbal collagen was shown to be progressively reinforced between postnatal days 10 and 28. The application of WAXS in some animal disease models has also shed some light on the structural basis of biomechanical homeostasis in the healthy eye, with studies in chicks (Boote et al, 2008; Morgan et al, 2013) and mice (Quantock et al, 2003b), pointing to the importance of a preferential circumferential alignment of a population of collagen fibrils at the limbus.…”

An explanation for the central to peripheral thickness variation in the mouse cornea

“…This implies either a postnatal role for extraocular muscle contraction in the adaptive modelling of the stromal lamellae or, more likely, the past influence of evolutionary pressures. In the mouse, corneal modelling, including completion of the limbal annulus, is not completed until the 28th postnatal day 49 . It may be relevant that in animals, which, like the primate, have frontally placed eyes, eye movements and thus activation of the extraocular muscles, play an important role in the location and tracking of visual targets whereas in animals with laterally placed eyes, such as the mouse, this function is subserved more by head movements.…”

“…In the mouse, corneal modelling, including completion of the limbal annulus, is not completed until the 28th postnatal day. 49 It may be relevant that in animals, which, like the primate, have frontally placed eyes, eye movements and thus activation of the extraocular muscles, play an important role in the location and tracking of visual targets whereas in animals with laterally placed eyes, such as the mouse, this function is subserved more by head movements. It is therefore of interest that the central region of the mouse cornea, unlike that of the human cornea, does not contain a significant amount of preferentially aligned, orthogonally disposed collagen.…”

Quantitative Assessment of Ultrastructure and Light Scatter in Mouse Corneal Debridement Wounds

“…This group's previous SAXS work has shown that the hydration of mouse corneas examined in this way does not significantly change, even after several minutes of x-ray exposure. 18,19 Specimen alignment was achieved by an initial exposure of x-ray-sensitive film placed in the specimen holder to locate the incident beam position. SAXS patterns, each resulting from an x-ray exposure of 5 seconds, were collected at 0.25-mm (horizontal) · 0.25-mm (vertical) intervals covering the whole of each cornea, and were recorded electronically on an x-ray detector placed 6 m behind the specimen position.…”