NCBI Summary:
Angiotensin II is a potent vasopressor hormone and a primary regulator of aldosterone secretion. It is an important effector controlling blood pressure and volume in the cardiovascular system. It acts through at least two types of receptors. This gene encodes the type 1 receptor which is thought to mediate the major cardiovascular effects of angiotensin II. AGTR1 may play role in the generation of reperfusion arrhythmias following restoration of blood flow to ischemic or infarcted myocardium. It was previously thought that a related gene AGTR1B exists; however, it is now believed that there is only one AGTR1 gene. The gene expresses at least four transcript variants; additional variants have been described but their full length nature has not been determined. Exon 5 contains the entire coding sequence and is present in all transcript variants.
General function
Receptor
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Cellular localization
Plasma membrane
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Ovarian function
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Expression regulated by
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Ovarian localization
Granulosa
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Li YH, et al reported the localization of angiotensin II in pig ovary and its effects on oocyte maturation in vitro.
The renin-angiotensin system (RAS) has been found in mammalian ovarian tissue; however, its physiological role is unclear. This study examined the content of angiotensin II (Ang II) in porcine follicular fluid (pFF), Ang II localization and its receptors in ovary, and the effects of Ang II on porcine oocyte maturation. The concentrations of Ang II were 6951.82+/-1295.83, 3502.99+/-679.10, 3147.89+/-690.60, and 2545.92+/-407.01pg/ml in pFF from small, medium, large, and extra-large follicles, respectively. In addition, Ang II was found on zona pellucidae (ZP) and granulosa cells by immunoreactive staining. The distribution of AT(1), an Ang II receptor subtype, was in accordance with that of Ang II. However, AT(2), another Ang II receptor, was mainly distributed in the stroma and thecal layers of follicles. When oocytes were cultured in media containing various concentrations of Ang II, a higher (P<0.05) proportion of oocytes reached metaphase II (MII) in the medium with 100ng/ml (87.0%) than without Ang II (61%). When oocytes from different sizes of follicles were separately cultured in media containing 100ng/ml Ang II, maturation rates were significantly higher in oocytes from small (61.5%) and medium (85.1%) follicles than that of their controls (45.1 and 72.6%, respectively). However, addition of Ang II inhibited nuclear maturation in oocytes from large follicles (77.8% versus 87.3%). Fertilization and male pronuclear (MPN) formation rates of oocytes matured in medium containing 100 or 1000ng/ml of Ang II were higher (P<0.05) than that of oocytes matured in medium containing 0 or 10ng/ml Ang II. Glutathione content in oocytes cultured for 44h in medium containing 100 or 1000ng/ml of Ang II was also higher (P<0.01) than that of oocytes cultured in medium containing 0 or 10ng/ml Ang II. In conclusion, Ang II was present in porcine ovaries and may regulate follicle growth and oocyte maturation.
Follicle stages
Antral, Corpus luteum
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Localization of angiotensin II, the AT1 receptor, angiotensin-converting enzyme, aminopeptidase A, adipocyte-derived leucine aminopeptidase, and vascular endothelial growth factor in the human ovary throughout the menstrual cycle. Harata T et al. OBJECTIVE: To assess the expression and cellular distribution of angiotensin II (Ang II), angiotensin type 1 receptor (AT1R), angiotensin-converting enzyme (ACE), aminopeptidase A (APA), adipocyte-derived leucine aminopeptidase (A-LAP), and vascular endothelial growth factor (VEGF) in human ovarian tissue during the menstrual cycle. DESIGN: Ovarian tissues (n = 52) and corpora lutea (n = 34) were obtained from patients undergoing hysterectomy/oophorectomy, and tissue sections were immunostained for each antigen. SETTING: University hospital. PATIENT(S): Patients undergoing hysterectomy or oophorectomy for benign conditions. INTERVENTION(S): Immunostaining of tissue sections using antibodies to each antigen. MAIN OUTCOME MEASURE(S): Microscopic evaluation to assess the presence, distribution, and cellular localization. RESULT(S): The luteal tissue is the major site of Ang II, ACE, AT1R, and VEGF, with highest staining intensity found during the midluteal phase and at pregnancy. The AT1R was found in theca cells. The APA was strongly immunolocalized in pericytes. Immunolocalization of AT1R was almost similar to that of VEGF including oocytes in the primordial and intermediate follicles. CONCLUSION(S): The expression and distinct pattern of the cellular localization of Ang II and its related proteins in human ovarian tissue during folliculogenesis and in the luteal tissue suggest their roles in the growth and differentiation of theca, granulose, and luteal cells.