在心脏缩中,APJ充当双重受体
Maria Cecilia Scimia1, Cecilia Hurtado, Saugata Ray
1Sanford-Burnham Medical Research Institute, La Jolla, California 92037, USA.
Nature
|July 20, 2012
概括
APJ受体的遗传损失通过作为机械传感器来预防心脏缩和心力衰竭. APJ将机械拉伸和阿佩林信号联系在一起,以调节心肌生长.
科学领域:
- 心脏病学 心脏病学
- 分子生物学分子生物学
- 生理学 生理学 生理学
背景情况:
- 心脏缩是对持续超负荷的适应性反应,但其病态进展导致心力衰竭.
- APJ受体及其连接物阿佩林与心血管调节有关.
研究的目的:
- 研究APJ受体在心脏缩和心力衰竭中的作用.
- 阐明APJ调解细胞对机械刺激和配体反应的机制.
主要方法:
- 使用了遗传功能丧失模型 (APJ-null小鼠) 和配体缺陷模型 (apelin-null小鼠).
- 评估心肌细胞对机械拉伸和阿佩林刺激的反应.
- 研究了下游信号通路,包括G蛋白和β-arrestin的参与.
主要成果:
- APJ-null小鼠对慢性压力过载诱导的心脏缩和心力衰竭表现出显著的抵抗力.
- 在心肌细胞中,APJ起到机械传感器的作用,在应对伸展时调解缩.
- 拉伸诱导的APJ激活是G蛋白独立的,而阿林诱导的激活是Gαi依赖的.
- 敲除β-arrestins或药理上诉治疗阻断了拉伸介导的缩.
结论:
- APJ是一种双功能受体,既能感知机械拉伸,也能感知的调用.
- APJ在将机械过载与心肌细胞缩和心力衰竭进展联系起来方面发挥着至关重要的作用.
- 通过APJ通过伸展和阿佩林激活的独特信号通路突出显示了心脏适应中的复杂调节机制.
相关概念视频
Transducer Mechanism: Enzyme-Linked Receptors
Enzyme-linked receptors are cell-surface receptors acting as an enzyme or associating with an enzyme intracellularly. They make excellent drug targets. Drugs can bind to the extracellular ligand-binding domain or directly affect their enzymatic domain and alter their activity.
Major types that are helpful drug targets include:
Major types that are helpful drug targets include:
Adrenergic Receptors: ɑ Subtype
Adrenoceptors are classified into α and ꞵ classes based on their potencies to catecholamine agonists. α-adrenoceptors show the following order of catecholamine potency:
Adrenaline ≥ Noradrenaline >> Isoprenaline
α-adrenoceptors are further divided into α1 and α2-adrenoceptors.
α1-Adrenoceptors: These receptors are located postsynaptically on the effector organs and cause constriction of smooth muscle mediated by activation of phospholipase C—inositol-1,4,5-trisphosphate...
Adrenaline ≥ Noradrenaline >> Isoprenaline
α-adrenoceptors are further divided into α1 and α2-adrenoceptors.
α1-Adrenoceptors: These receptors are located postsynaptically on the effector organs and cause constriction of smooth muscle mediated by activation of phospholipase C—inositol-1,4,5-trisphosphate...
Adrenergic Receptors: β Subtype
β-adrenoceptors have varied sensitivities towards adrenaline, noradrenaline, and isoprenaline. The order of agonist potency is as follows:
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors have equal affinities for...
Antihypertensive Drugs: Angiotensin II Receptor Blockers
In the renin-angiotensin-aldosterone system, a hormone called angiotensin II plays a crucial role. It binds to the AT1 receptors in vascular smooth muscles coupled with Gq proteins. The activation of these receptors activates an enzyme called phospholipase C, which releases two molecules: inositol trisphosphate and diacylglycerol. These molecules cause a chain reaction that leads to the phosphorylation of myosin light chains and promotes interaction between actin and myosin, leading to smooth...
Heart Failure Drugs: Inhibitors of Renin-Angiotensin System
The activation of the sympathetic nervous system and the renin-angiotensin-aldosterone system (RAAS) contributes to cardiac remodeling, and inhibiting the RAAS is a pharmacological target in heart failure management. As a result, neurohumoral modulation is a crucial treatment principle for managing heart failure. This approach involves using medications like ACE inhibitors (ACEIs), angiotensin receptor blockers (ARBs), β-blockers, mineralocorticoid receptor antagonists (MRAs), and neutral...
Cardiomyopathy III: Hypertrophic Cardiomyopathy
Hypertrophic cardiomyopathy, or HCM, is an autosomal dominant genetic disorder characterized by asymmetric left ventricular hypertrophy without ventricular dilation. It is more common in men and is typically diagnosed in young, athletic adults.EtiologyHCM is primarily genetic and is caused by mutations in genes encoding sarcomeric proteins. Researchers have identified over 1400 mutations across at least 11 different genes. Among these, the most frequently occurring mutations are found in the...


