Função dos Lipídios na Estrutura Epidérmica
publicado em 01/04/1992
D T Downing, PhD
University of Iowa College of Medicine, lowa City IA, Estados Unidos
Este artigo tem como objetivo resumir os recentes estudos sobre o papel dos lipídios na estrutura e função do estrato córneo, colocando-os em perspectiva com o desenvolvimento do conhecimento da epiderme durante os últimos 30 anos e relacionar Os novos conhecimentos com as propriedades amplamente aceitas do funcionamento da epiderme como barreira.
Ultraestrutura Epidérmica
Lipídios e a Barreira Epidérmica
Há muito tempo foi reconhecido que a epiderme proporciona uma barreira eficiente à penetração da água e de outras substâncias. Pesquisadores anteriores mostraram que a barreira está localizada no estrato córneo, mas, comumente, acreditavam que as propriedades da barreira estavam confinadas às poucas camadas de células mais profundas. Esta interpretação parecia razoável, baseada no aspecto das seções histológicas padrão que mostram o estrato córneo como possuindo uma estrutura de trama de estaria aberta (stratum disjunctum), onde somente as poucas camadas inferiores (stratum compactum) estão unidas. Entretanto, Kligman demonstrou que o estrato córneo não fixado está ligado e possui função de barreira através da sua espessura.1
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