X-Ray Microanalysis of Cryopreserved Human Skin to Study the Effect of Iontophoresis on Percutaneous Ion Transport1.

Autor: Pechtold, Louk, Boddé, Harry, Junginger, Hans, Koerten, Henk, Bouwstra, Joke
Zdroj: Pharmaceutical Research; Jul2001, Vol. 18 Issue 7, p1012-1017, 6p
Abstrakt: Purpose. To study at the ultrastructural level which part of the skin is associated with percutaneous iodide transport by passive diffusion and iontophoresis. Methods. Following passive diffusion or iontophoresis of iodide, the morphology and the ion distribution of the skin was preserved by rapid freezing. The skin was kept frozen until and during examination by transmission electron microscopy (TEM) and X-ray microanalysis (XRMA). The intrinsic electron absorbing characteristics of cryopreserved skin allow direct TEM examination without additional staining. XRMA can be used to obtain in a relatively nondestructive way in situ information on ion distributions across the skin. Results. After passive diffusion, iodide was mainly found in the stratum corneum (SC), whereas there was little iodide in the viable epidermis. Iontophoresis up to 300 μA/cm2 did not significantly affect this distribution. With iontophoresis at 1000 μA/cm2, the amount of iodide increased dramatically and was equally distributed over the SC and viable epidermis. The presence of iodide in the SC suggests that iodide is present inside corneocytes. Conclusions. Iontophoresis up to 300 μA/cm2 does not significantly perturb skin structures in contrast to iontophoresis at 1000 μA/cm2. The presence of iodide inside corneocytes suggests the possibility of transcellular percutaneous iodide transport. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index