Effect of steroid hormones on Bufo arenarum oviduct. Ultrastructural study.

MEDINA MF; CRESPO CA; CISINT SB; RAMOS I; FERNANDEZ SN

Journal of Experimental Zoology. Part A. Ecological Genetics and Physiology

Wiley- Liss

Lugar: New Yersey USA; Año: 2006 vol. 307 p. 1 - 12

1932-5223

The endocrine regulation of the mucosa of the oviductal pars convoluta was analyzed by ultrastructural studies demonstrating that ovariectomy, together with a decrease in ovarian steroids circulating levels, caused a marked regression in this portion of Bufo arenarum oviduct. Twenty-five days after ovariectomy, a decrease in the depth of the epithelial and glandular layers was observed due to the notable loss of secretory cells, whose number was clearly smaller than in non ovariectomized females. The remaining secretory cells showed involution signs, with few secretory granules in their cytoplasm, little endoplasmic reticulum near poorly developed Golgi complexes and a large amount of lipid droplets. Cells in an advanced autolysis state were found in the lumen. These characteristics evidence a non functional state of the pars convoluta. Treatment with 5a-dihydrotestosterone (DHT) completely reversed the ovariectomy effect, inducing pars convoluta growths and restoring the characteristics of epithelial and glandular secretory cells in the whole pars convoluta, with micrographs similar to the control. These same effects were observed after treatment with estradiol-17b (E2), progesterone (P) o E2 + P in the glandular layer of the whole pars convoluta, but only in the epithelial layer of the most anterior region of this duct. In the secretory cells of other segments these treatments induced the formation of granules of high electron density and homogeneous aspect. Each steroid had a particular effect on the pars convoluta. While E2 and DHT induced the development of the organoids involved in the proteins biosynthesis, P and DHT acted as secretagogues.