Organization of the fibrous connective tissue of the fallopian tubes in fertile and climacteric periods: a scanning electron microscopic and stereologic study.

The extracellular matrix (ECM) of the fallopian tubes is subject to several changes due to hormonal influences and aging. However, there is a lack of studies regarding its arrangement in older women. We aimed to analyze the organization of ECMcomponents, including collagen and elastic fibers, in the fallopian tube's ampulla from young and old women by means of scanning electron microscopical and stereological methods. Twenty-one samples were analyzed: 12 from female cadavers in a fertile age (G1) and 9 from the climacteric period (G2). Masson's trichrome stain was used to observe collagen and smooth muscle, while Weigert's Fuchsin-Resorcin was employed to observe elastic fibers. Statistical analysis was performed by the Wilcoxon-Mann-Whitney test with the aid ofthe R software. The tissue was also fixed for scanning electron microscopic analysis in a modified Karnovsky solution and the three-dimensional organization of fibrous connective tissue was observed and compared. Statistically significant differences (P < 0.01) were found in all stereologic comparisons of the extracellular matrix between the groups, which revealed a higher volumetric density of the fibrous tissue in the climacteric group. Scanning electron microscopy showed degenerative alterations of extracellular matrix. According to our results, aging caused significant changes to the elements of the extracellular matrix and the smooth muscle of the fallopian tubes.