An electron microscopic study of fetal capillary basal laminas of "normal" human term placentas.
Electron microscopic examination of terminal (free-floating) villi of definable normal human term placentas emphasizes the variable fine structural appearance of the fetal capillary basal lamina (FL). The FL assumes both a unilaminar and multilamellar configuration in each placenta examined; the multilamellar portions are usually composed of individual layers which tend to branch and anastomose. The constant indentification of collagen fibrillar profiles between these electron-dense layers argues against the notion that the multilamellar portions of the FL arise via a simple splitting or disaggregation of pre-existing unilaminar FL's.
D000293:Adolescent; D000328:Adult; D002196:Capillaries / Q000648:ultrastructure*; D002199:Capillary Permeability; D004727:Endothelium / Q000166:cytology; D005321:Extraembryonic Membranes / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D008423:Maternal Age; D008854:Microscopy, Electron; D008867:Microtomy; D010298:Parity; D010920:Placenta / Q000098:blood supply / Q000166:cytology / Q000648:ultrastructure*; D011247:Pregnancy; D013048:Specimen Handling; D013194:Staining and Labeling; D014327:Trophoblasts / Q000648:ultrastructure