Filters
Histogenesis of the Uterine Horn in the Domestic Cat (Felis silvestris catus): LM, TEM, and SEM Study
This study employs light microscopy, scanning electron microscopy, and transmission electron microscopy to describe the morphological changes occurring during the development of the domestic cat’s uterine horns, originating from the uterine segments of paramesonephric ducts (uPD). Comprehensive observations conducted on 60 specimens aged 28–63 days post-conception (p.c.) revealed that the formation of the endometrium and myometrium in the uterine horns begins around day 33 p.c., initiated by mesenchymal differentiation. During endometrial development, fibroblasts align first in perpendicular and then in oblique columns. The subdivision of the lamina propria into basal and functional layers becomes evident shortly before birth, with the functional layer remaining flat until the end of the prenatal period. The endometrial epithelium transforms from a simple columnar to a pseudostratified structure, undulating by day 63 p.c. Myometrial formation commences with the differentiation of myoblasts, which are arranged in a circular pattern. By the end of gestation, these myoblasts differentiate into smooth muscle cells, organizing into distinct inner circular and outer longitudinal sublayers. Although the fundamental layered architecture of the uterine wall is established before birth, its full maturation—including gland formation, epithelial transformation, and further development of the myometrium—continues postnatally.
Analiza rozwoju sznurów płciowych i kanalików sieci jajnika w aspekcie różnicowania komórek pęcherzykowych i ich relacji z komórkami linii płciowej u kota domowego (Felis silvestris catus)
Prenatal development of the intramural vascular system of the uterine tube in the European shorthair cat
Context:Early vascular development during the prenatal period is essential for the proper formation of all organs, including the reproductive system.Aims: This study aimed to characterize the development of the intramural vascular system in the domestic cat's uterine tube, with emphasis on changes associated with wall layer formation.Methods: Uterine tubes from 38 domestic cat fetuses (36-63 days post-conception) were examined using light microscopy, vascular corrosion casts, and scanning electron microscopy.Key Results:In early stages, the vascular system of the rudimentary paramesonephric duct (uPD) is simple, comprising longitudinal vessels and a superficial vascular network. Initially, all vessels resemble capillaries. By days 42-43 p.c., vascular differentiation into arterioles and venules becomes evident, progressing to arteries and veins with distinct surface relief visible on corrosion casts by late gestation. Around day 50 p.c., as the layers develop in the uterine tube wall, a subepithelial capillary network emerges, connecting with the superficial vascular system. At term, the uterine artery becomes tortuous and branches above the isthmus; veins accompany the arteries. The mature intramural vascular system includes circumferential arteries and veins, as well as subepithelial and subserosal capillary networks.Conclusions:A basic vascular architecture supporting tissue growth develops prenatally, laying the foundation for postnatal expansion linked to mucosal and muscular layer maturation.Implications:This first-time analysis of feline uterine tube prenatal angioarchitecture provides novel insights into reproductive system histogenesis in a species both common in human environments and important in veterinary science.