Endothelin expression in salivary gland

Abstract

a b s t r a c tThe present paper reviews the roles of endothelin (ET) in the rat submandibular gland (SMG). ET and its mRNA are expressed in the granular convoluted tubule (GCT) segment by immunostaining and in situ hybridization, respectively. ET is synthesized in granular cells of the GCT segment, stored in secretory granules, and secreted into the oral cavity. It is well known that granular cells in the GCT segment of the SMG in mice and rats express many kinds of growth factor such as epidermal growth factor and nerve growth factor. These growth factors are discharged into saliva and thought to regulate oral-esophageal and gastrointestinal mucosa. ET acts as a potent vasoconstrictor with mitogenic property and is excreted from Weibel-Palade bodies in vascular endothelial cells. ET in the salivary origin may regulate its own functions as noted in the endothelial origin. This review deals with comparative discussion of ET and other growth factors, which originate from GCT segments in rodents.

A mesenchymal to epithelial switch in Fgf10 expression specifies an evolutionary-conserved population of ionocytes in salivary glands

“…Several reports indicate that GCT subpopulations labeled by Kit ( Kwak et al, 2018 ), Slc4a11 ( Roussa et al, 1998 ), luminal localization of ATPases ( Lee et al, 2012 ), and IP3R2 in “pioneer cells” ( Yamamoto-Hino et al, 1998 ), all express markers enriched in ionocytes. Similarly, several cell populations have been described based on morphology, such as “pillar cells” ( Mori et al, 2011 ) and “Tuft cells” ( Sato et al, 1998 ; Sato and Miyoshi, 1997 ). We suggest that all these previously described cell types are SG ionocytes.…”

Serum big endothelin-1 as a biomarker in oral squamous cell carcinoma patients: an analytical study

“…So circulating levels of plasma or serum big ET-1 (precursor) being a stable peptide with plasma half life of 30 minutes may serve as a sensitive indicator of endothelin system activation 23 . The ET-1 levels can be measured in different body fluids like human plasma, saliva, cerebro-spinal fluid, urine, pericardial fluid, breast milk, and amniotic fluid even if the levels vary 25 . Although salivary levels of ET-1 were reported as higher than serum levels in oral cancer, it failed to show positive correlation with disease activity 16 , 28 .…”

Submandibular Gland Pathogenesis Following SARS-CoV-2 Infection and Implications for Xerostomia

“…Unlike humans, whose submandibular glands' (SMGs) ducal system contains three segments, the SMGs in rodents contain four segments: the intercalated duct, the granular convoluted tubule (GCT), the striated duct and the excretory duct. The GCT is a specific segment between the intercalated and the striated ducts [11], found more frequently in male than in female rodents due to its responsiveness to androgens [12]. These tubules are composed of granular epithelial cells whose granules contain several growth factors, including epidermal growth factor (EGF) [11,12], a mitogenic factor essential for cell growth, differentiation and proliferation, favoring tissue repair [13,14].…”

“…The GCT is a specific segment between the intercalated and the striated ducts [11], found more frequently in male than in female rodents due to its responsiveness to androgens [12]. These tubules are composed of granular epithelial cells whose granules contain several growth factors, including epidermal growth factor (EGF) [11,12], a mitogenic factor essential for cell growth, differentiation and proliferation, favoring tissue repair [13,14]. Moreover, the binding of EGF to its receptor (EGFR) triggers anti-apoptotic pathways [15,16].…”