RESUMO
BACKGROUND: We characterize the application of multiphoton microscopy to the observation of the extracellular matrix of fresh unstained vessels. METHOD: Combined two-photon-excited fluorescence (2PEF) and second harmonic generation (SHG) imaging of large arteries reveals the architecture of elastin and collagen fibers in the vessel wall with remarkable specificity. RESULTS: We present elastin/collagen imaging in unstained rat vessels at both micrometer and whole vessel scales, and we characterize the optical properties of rat carotid artery and aorta walls. We apply this method to evidence deleterious effects of residual doses of a pesticide on the vessel wall. CONCLUSION: This study illustrates the potential of 2PEF/SHG microscopy for pharmacological studies in unlabeled arteries.
Assuntos
Vasos Coronários/ultraestrutura , Matriz Extracelular/metabolismo , Animais , Artérias Carótidas/metabolismo , Artérias Carótidas/ultraestrutura , Colágeno/metabolismo , Colágeno/ultraestrutura , Vasos Coronários/metabolismo , Elastina/metabolismo , Elastina/ultraestrutura , Matriz Extracelular/ultraestrutura , Feminino , Interpretação de Imagem Assistida por Computador , Técnicas In Vitro , Masculino , Microscopia de Fluorescência por Excitação Multifotônica , Ratos , Ratos Sprague-DawleyRESUMO
We recorded one-photon excited fluorescence (1PEF) and two-photon excited fluorescence (2PEF) spectra of purified keratin from human epidermis, and determined the action cross section of this endogenous chromophore. We used this spectroscopic analysis to analyse multiphoton images of skin biopsies and assign the intrinsic fluorescence signals in the epidermis. We observed a good agreement between in situ and in vitro 2PEF spectra of keratin. This study provides a comprehensive characterization of the 2PEF signal of the keratins from the epidermis, and will be of practical interest for multiphoton imaging of the skin.
RESUMO
We present corrected versions of the list of authors and of Section 2.1.