Prenatal development of the human submandibular gland.
The prenatal development of the human submandibular gland has been investigated in 26 fetuses from the 10th week of gestation to full term. At 10-12 weeks, the glandular elements (primitive ducts and acini) were immature and surrounded by a loose mesenchyme. The acinar cell population increased gradually till the age of 32 weeks, and the rate of increase was diminished thereafter. At 16 weeks, intercalated and striated ducts were distinguished and their number increased till the age of 32 weeks when their number seemed to be stabilized. The development of the granular convoluted tubule cells from the proximal segments of striated ducts occupied the later stages of development. They appeared around the age of 20 weeks and proceeded till full term. At birth, the gland appeared devoid of mucous acini and fat cells and the secretory end-pieces were of the serous type. During the second trimester, periodic acid-Schiff- and alcian blue-positive secretory materials appeared in the epithelial cells of both ducts and acini, and in their lumina. This secretory activity was transitory and disappeared around the age of 28 weeks. The possible function of these secretory products is discussed.
Department of Anatomy and Histology, Faculty of Medicine, Mansoura University, Egypt.
E A
EA
el-Mohandes
K G
KG
Botros
A A
AA
Bondok
D003593:Cytoplasm / Q000648:ultrastructure; D004848:Epithelium / Q000196:embryology / Q000648:ultrastructure; D005865:Gestational Age; D006651:Histocytochemistry; D006801:Humans; D013363:Submandibular Gland / Q000196:embryology* / Q000378:metabolism / Q000648:ultrastructure