Ultrastructural examination of basement membrane pathology in horses with insulin-induced laminitis.
Domest Anim Endocrinol
; 69: 30-34, 2019 10.
Article
em En
| MEDLINE
| ID: mdl-31280023
ABSTRACT
The third phalanx of the equine digit is suspended within the hoof capsule by a specialized interdigitating dermoepidermal layer called the lamellae, which fails during laminitis. Pathology of the basement membrane (BM), which interfaces epidermis and dermis, is evident during acute laminitis. However, BM damage appears to be less prevalent in ponies with the insulin-associated form of laminitis. The aim of the present study was to investigate changes to the ultrastructure and morphometry of the lamellar BM in the acute phase of insulin-induced laminitis in horses. Lamellar tissue from the left forefoot of 3 horses with acute hyperinsulinemic laminitis was examined with transmission electron microscopy and compared with tissue from normal horses. Lamellar BM width and hemidesmosome (HD) density were assessed every 5 µm along â¼200 µm of secondary epidermal lamellar BM. The BM zone of treated horses was extensively disorganized with loss of uniformity of the lamina lucida and lamina densa, fragmentation and disorientation of HDs, and cytoskeletal disengagement of the HDs. The mean (±SD) lamellar BM was twice as wide in treated (0.25 ± 0.05 µm), compared with control (0.14 ± 0.02 µm), horses. The HD density (HDs/µm) was reduced by half in the treatment group (1.88 ± 0.37), compared with controls (3.6 ± 0.13). The reduced number of HDs in horses with laminitis may contribute to the weakening of the dermoepidermal junction and lamellar failure. Disassembly of HDs during excessive cellular proliferation, secondary to hyperinsulinemia, may account for HD loss. Further investigation of the underlying etiopathogenesis of BM dysfunction during hyperinsulinemic laminitis in horses may facilitate an improved understanding of the disease.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Membrana Basal
/
Doenças do Pé
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Casco e Garras
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Doenças dos Cavalos
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Inflamação
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Insulina
Tipo de estudo:
Observational_studies
/
Risk_factors_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article