Localization of the progesterone receptor in the porcine ovary.

Regulation of progesterone receptor (PR) expression has been studied in many species. However, precise studies have not yet been performed in the porcine ovary. We have examined the localization of PR in follicles and corpora lutea of the porcine ovary at different stages of their development. The effects of LH and FSH on PR expression in granulosa cells of small antral follicles was also studied. Immunohistochemistry was applied to determine the distribution of PR while immunoblot analysis showed that two isoforms A and B were present. Early antral follicles contained PR in the granulosa layer. In granulosa cells of small and medium antral follicles PR was not detected whereas it was present in the theca layer. Before ovulation, PR was found in both granulosa and theca cells of large follicles and the staining intensity was very strong. FSH or LH treatment of small follicles (100 ng/ml) induced changes in cellular distribution patterns of PR. In both cases, PR was expressed in granulosa cells. PR was detected in corpora lutea in all 3 stages of the luteal phase. Our data show that in the pig ovary changes in PR localization are stage-specific and suggest that expression of PR is positively regulated by both LH and FSH.

Linseed oil based nanocapsules as delivery system for hydrophobic quantum dots.

In the present work, the CdSe/ZnS hydrophobic quantum dots were embedded within the polyelectrolyte nanocapsules. The core of the capsules, which consists of a mixture of the linseed oil with chloroform, was prepared using the spontaneous emulsification technique. The obtained emulsions were stabilized with lecithin and encapsulated using the layer-by-layer (LbL) adsorption of polyelectrolytes. The pair of biocompatible polyelectrolytes was used: the cationic poly-l-lysine hydrobromide (PLL) together with the anionic poly-d-glutamic acid sodium salt. The saturation LbL method, which is based on the stepwise formation of consecutive layers on the initial emulsion without the intermediate rinsing step, was applied to form the capsule shells. Their growth was evidenced by the capsule size and electrophoretic mobility measurements. The emulsion and the capsules were deposited on a mica surface and the deposit topology was examined by the means of atomic force microscopy (AFM). The presence of quantum dots within the oil cores was confirmed by recording the fluorescent spectra of the samples containing CdSe/ZnS. In order to evaluate cytotoxicity of the capsules, their influence on the viability of mouse embryonic fibroblasts was examined using the MTT test, followed by optical-microscope observation of morphology of the cells after hematoxylin-eosin staining.