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Blastocystenimplantation bei der Hauskatze Lidit‐ und elektronenmikroskopisdie Untersuchung *
Author(s) -
Leiser R.
Publication year - 1979
Publication title -
anatomia, histologia, embryologia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.34
H-Index - 35
eISSN - 1439-0264
pISSN - 0340-2096
DOI - 10.1111/j.1439-0264.1979.tb00681.x
Subject(s) - trophoblast , cytotrophoblast , epithelium , syncytiotrophoblast , blastocyst , placenta , endometrium , microbiology and biotechnology , biology , embryo , andrology , endocrinology , fetus , pregnancy , embryogenesis , medicine , genetics
Summary Blastocyst implantation in the domestic cat A light and electronmicroscopic investigation Implantation in the cat begins 121/2 days post coitum and lasts to the 14th day. Several hours before implantation begins the extraembryonic trophoblast, in what could be considered a precontact or sensitization phase, shows fine structural evidence of secretory activity. The uterine epithelium at the same times gives evidence of being at first resorptive and, after a differentiation, of being secretory. Secretion also in the gland epithelium can be observed. The attachment of the embryo to the endometrium begins with an appositional phase. The trophoblast is now distinctly resorptive and forms with the uterine epithelium microvilli‐free areas of contact lying between the openings of the uterine glands. Then follows an adhesion phase during which additional junctional complexes are formed between an actively proliferating trophoblast and the uterine epithelium which shows now symplasmic differentiation. Finally, in the intrusion phase the uterine epithelium completely disintegrates. In this manner the syncytiotrophoblast which differentiates from the cytotrophoblast invades the maternal tissues until it reaches the endothelium of the uterine blood vessels.