Scanning and transmission electron microscopic analysis of ampullary segment of oviduct during estrous cycle in caprines

Abstract

The ampullary segment of the mammalian oviduct provides suitable milieu for fertilization and development of zygote before implantation into uterus. It is, therefore, in the present study, the cyclic changes in the morphology of ampullary segment of goat oviduct were studied during follicular and luteal phases using scanning and transmission electron microscopy techniques. Topographical analysis revealed the presence of uniformly ciliated ampullary epithelia, concealing apical processes of non-ciliated cells along with bulbous secretory cells during follicular phase. The luteal phase was marked with decline in number of ciliated cells with increased occurrence of secretory cells. The ultrastructure analysis has demonstrated the presence of indented nuclear membrane, supranuclear cytoplasm, secretory granules, rough endoplasmic reticulum, large lipid droplets, apically located glycogen masses, oval shaped mitochondria in the secretory cells. The ciliated cells were characterized by the presence of elongated nuclei, abundant smooth endoplasmic reticulum, oval or spherical shaped mitochondria with crecentric cristae during follicular phase. However, in the luteal phase, secretory cells were possessing highly indented nucleus with diffused electron dense chromatin, hyaline nucleosol, increased number of lipid droplets. The ciliated cells had numerous fibrous granules and basal bodies. The parallel use of scanning and transmission electron microscopy techniques has enabled us to examine the cyclic and hormone dependent changes occurring in the topography and fine structure of epithelium of ampullary segment and its cells during different reproductive phases that will be great help in understanding major bottle neck that limits success rate in vitro fertilization and embryo transfer technology.

Repeated hyperstimulation affects the ultrastructure of mouse fallopian tube epithelium

“…We found that, after 4R and 8R, the tunicae mucosa and muscularis of mouse FTs appeared well-preserved by LM with no evident signs of morphological alterations, as in other mammals [ 45 , 46 ]. The ultrastructural analysis of CECs by TEM showed, in all groups, the presence of well-preserved nuclei and cell junctions, lipid droplets, ER tubules/networks, Golgi apparatuses, secondary lysosomes, multivesicular bodies and microvilli, in accordance with the literature describing the physiological morphology of oviducts [ 23 , 24 , 27 ]. However, electron microscopy evidenced specific changes affecting mitochondria and cilia of the CECs of the mucosa layer, especially after 8R.…”

“…All the experimental procedures and the animals were maintained in accordance with national and international law and policies (European Economic Community Council Directive 86/609, OJ 358, 1 Dec 12, 1987; Italian Legislative Decree 116/92, Gazzetta Ufficiale della Repubblica Italiana n. 40, Feb 18, 1992; National Institutes of Health Guide for the Care and Use of Laboratory Animals, NIH publication no. 85- 23,1985). The Italian Ministry of Health and the local committee (University of L'Aquila) for the animal care and use approved the experimental protocols, in compliance with the accepted veterinary medical practice.…”

“…Physiological/pathological changes of FT epithelium have been found in different species as rat [ 20 ], hamster [ 21 ], pig [ 22 ], goat [ 23 ] and horse [ 24 ]. Also, the ultrastructural features of mucosa and epithelial cells, such as the presence, distribution, and location of secretory and ciliated cells in the various portions of the human and murine FTs during the hormonal cycle have been described [ 25 , 26 ].…”

The morphological changes of oviductal mucose in oestral cycle of sows

“…The folds are longitudinally different, forming secondaryto -tertiary folds, forming irregular net-like structures forming different troughs, vesicles and crypts (Yaniz et al, 2000;Kenngott and Sinowatz, 2007). Sharma et al (2015) describes characteristic pattern of variations in the ampullary segment of the uterine tube during follicular and luteal phases of estrous cycle in goat. The tunica mucosa of ampulla was characterized by presence of longitudinal mucosal folds throughout the length with extensive secondary and tertiary branches in follicular phase, whereas the luteal phase was characterized by primary and secondary branching patterns.…”

Upregulation of peroxisome proliferator-activated receptor-α and the lipid metabolism pathway promotes carcinogenesis of ampullary cancer

“…Previous research suggested a correlation between survival of ampullary cancer patients and expressions of membrane receptors for bile acids [9]. Genetic polymorphisms of lipid metabolism-related genes were correlated with the development of biliary tract cancer and ampullary cancer [10,11]. The mechanism of development of ampullary cancer remains inexplicit, and comprehensive analyses are required.…”