Buddle Alice L, Otway Nicholas M, Van Dyke James U, Thompson Michael B, Murphy Christopher R, Dowland Samson N, Simpfendorfer Colin A, Ellis Megan T, Whittington Camilla M
School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia.
New South Wales Department of Primary Industries, Port Stephens Fisheries Institute, Taylors Beach, New South Wales, Australia.
J Morphol. 2020 Apr;281(4-5):428-437. doi: 10.1002/jmor.21109. Epub 2020 Feb 7.
Embryos of the viviparous dwarf ornate wobbegong shark (Orectolobus ornatus) develop without a placenta, unattached to the uterine wall of their mother. Here, we present the first light microscopy study of the uterus of O. ornatus throughout pregnancy. At the beginning of pregnancy, the uterine luminal epithelium and underlying connective tissue become folded to form uterine ridges. By mid to late pregnancy, the luminal surface is extensively folded and long luminal uterine villi are abundant. Compared to the nonpregnant uterus, uterine vasculature is increased during pregnancy. Additionally, as pregnancy progresses the uterine epithelium is attenuated so that there is minimal uterine tissue separating large maternal blood vessels from the fluid that surrounds developing embryos. We conclude that the uterus of O. ornatus undergoes an extensive morphological transformation during pregnancy. These uterine modifications likely support developing embryos via embryonic respiratory gas exchange, waste removal, water balance, and mineral transfer.
胎生侏儒华丽须鲨（Orectolobus ornatus）的胚胎在发育过程中没有胎盘，也不附着于母体的子宫壁。在此，我们展示了对妊娠全过程中O. ornatus子宫进行的首次光学显微镜研究。妊娠初期，子宫腔上皮及其下方的结缔组织折叠形成子宫嵴。到妊娠中后期，腔面广泛折叠，且有大量长的腔内子宫绒毛。与未怀孕的子宫相比，妊娠期间子宫血管增多。此外，随着妊娠进展，子宫上皮变薄，以至于将大的母体血管与围绕发育中胚胎的液体分隔开的子宫组织极少。我们得出结论，O. ornatus的子宫在妊娠期间经历了广泛的形态学转变。这些子宫的改变可能通过胚胎呼吸气体交换、废物排出、水平衡和矿物质转运来支持发育中的胚胎。
