プレエクランプ患者からの抗体は,アニオテンシン受容体の活性化を通じて,細胞内Ca2+の活性化を促進します
Theingi M Thway1, Sergiy G Shlykov, Mary-Clare Day
1Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
Circulation
|September 24, 2004
まとめ
アンジオテンシンII型I (AT1) 受容体を標的とする母性抗体は,これらの受容体を活性化させ,出産前の患者に細胞内カルシウムレベルを上昇させます. この発見は,AT1受容体-アゴニスティック抗体 (AT1-AAs) を,妊娠前出血症に見られる細胞変化と関連付けています.
科学分野:
- 産婦人科と産婦人科を担当しています.
- 免疫学 免疫学とは
- 心血管生理学 心血管の生理学
背景:
- 予備妊娠症は,高血圧と血管異常によって特徴づけられる妊娠障害です.
- 妊娠前の不妊症における細胞の変化には,細胞内カルシウムの上昇が含まれます.
- アンジオテンシンII型I (AT1) 受容体に対する抗体は,子閉塞前症に関連しています.
研究 の 目的:
- AT1受容体-アゴニスティック抗体 (AT1-AAs) がAT1受容体を活性化するかどうかを調査する.
- AT1-AAが細胞内カルシウムを増やし,下流の信号伝達経路を活性化するかどうかを判断する.
主な方法:
- 妊娠中の30人の妊婦のIgG検査 (16人の妊娠前出血圧患者,14人の妊娠前出血圧患者) で,細胞内カルシウムを動員する能力について調べました.
- ロサルタンと特定のペプチドアンタゴニストを用いてAT1-AAの活性阻害を試験した.
- AT1-AA刺激後の活性化T細胞の核因子 (NFAT) の活性化評価.
主要な成果:
- すべてのプレエクランプ患者からのIgGはAT1受容体を活性化させ,細胞内フリーカルシウムを増加させた.
- ノルモテンシブな個体では,IgGがAT1受容体を活性化していない.
- AT1-AA誘発のカルシウム運動はロサルタンとペプチドアンタゴニストによって阻害され,NFATが活性化されました.
結論:
- 母親のAT1-AAAはAT1受容体を活性化させ,細胞内カルシウムの増加につながります.
- これらの抗体は,予備妊娠中症における細胞変化と遺伝子発現の変化に寄与する可能性があります.
関連する概念動画
01:33Hormonal Regulation
The renin-aldosterone system is an endocrine system which guides the renal absorption of water and electrolytes, thus managing blood pressure and osmoregulation. Activation of the system begins in the kidneys with a small cluster of cells adjacent to the afferent and efferent blood vessels of the renal corpuscle. As the nephrons are filtering blood, juxtaglomerular cells monitor blood pressure. If they detect a decrease in pressure, they release the hormone renin into the bloodstream.
01:25cAMP-dependent Protein Kinase Pathways
Cyclic Adenosine Monophosphate (cAMP) is an essential second messenger that activates protein kinase A (PKA) and regulates various biological processes. A single epinephrine molecule binds to GPCR and activates several heterotrimeric G proteins, each stimulating multiple adenylyl cyclase, amplifying the signal, and synthesizing large numbers of cAMP molecules. Small changes in cAMP concentration affect PKA activity. The binding of four cAMP molecules induces a conformational change in PKA,...
01:16Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
01:30Antihypertensive Drugs: Angiotensin-Converting Enzyme Inhibitors
Angiotensin-converting enzyme (ACE), a vital component of the renin-angiotensin-aldosterone system, is abundant in lung endothelial cells. ACE converts the inactive decapeptide, angiotensin I, into the active octapeptide, angiotensin II. This potent vasoconstrictor narrows blood vessels, increasing resistance to blood flow and elevating blood pressure. Angiotensin II also stimulates aldosterone production, encouraging kidney cells to reabsorb more sodium and water from urine, thereby increasing...
01:25Antihypertensive Drugs: Direct Renin Inhibitors
The renin-angiotensin-aldosterone system (RAAS) is an intricate physiological pathway involving numerous enzymes and hormones, including renin, angiotensin-converting enzyme (ACE), angiotensin I and II, and aldosterone. Imbalances within this system increase the production of angiotensin II and aldosterone. Increased angiotensin II levels promote vasoconstriction and blood pressure elevation. Concurrently, higher aldosterone levels stimulate sodium and water reabsorption in the kidneys,...
01:29Hypertension II: Pathophysiology
Hypertension is a chronic condition in which the blood's force against artery walls is excessively high, posing risks such as heart disease. The condition's underlying mechanisms involve complex interactions among the cardiovascular, kidney, and autonomic nervous systems.Renin-Angiotensin-Aldosterone System (RAAS): This system significantly influences blood pressure regulation. When blood pressure decreases, the kidneys secrete renin. This enzyme transforms angiotensinogen, a plasma protein,...