衰老对细胞内Ca2 +,pHi和在缺血和再输液期间收缩性的影响
1Department of Surgery, Harvard Medical School, Boston, MA.
Circulation
|November 1, 1992
概括
衰老会增加细胞质 (Ca2+) 在缺血期间的积累,导致心脏功能减少. 与成熟的心脏相比,老年心脏的恢复受损,较高的Ca2+水平与功能下降相关.
科学领域:
- 心血管生理学心血管生理学
- 衰老研究研究 衰老研究
- 缺血-再输液损伤 缺血-再输液损伤
背景情况:
- 衰老会影响心肌肌肉对缺血和再注射损伤的敏感性.
- 关键因素如细胞质 (Ca2+) 和细胞内pH值 (pHi) 都与此有关.
研究的目的:
- 调查衰老对心肌缺血和再注射损伤的影响.
- 评估细胞 Ca2+,pHi 和机械性能中的与年龄相关的变化.
主要方法:
- 使用来自成熟和老年群体的隔离 perfused 子心脏.
- 心脏经历了正常热缺血和再输血.
- 用光指标 (fura-2,BCECF) 测量了细胞质Ca2+和pHi.
主要成果:
- 与成熟心脏相比,老年心脏在缺血期间细胞质Ca2+的增加显著增加.
- 这两组在缺血期间都经历了类似的PHI下降.
- 左心室峰压的功能恢复在老年心脏 (55%) 和成熟心脏 (84%) 中明显较低.
结论:
- 老年心脏在缺血期间呈现增加的Ca2+积累,与功能恢复的减少相关.
- 老年心脏中Ca2+升高的原因并不是由于酸性疾病缓冲能力的差异.
相关概念视频
Necrosis
Necrosis is considered as an “accidental” or unexpected form of cell death that ends in cell lysis. The first noticeable mention of “necrosis” was in 1859 when Rudolf Virchow used this term to describe advanced tissue breakdown in his compilation titled “Cell Pathology”.
Morphological Manifestations of Necrosis
Necrotic cells show different types of morphological appearance depending on the type of tissue and infection. In coagulative necrosis, cells become anucleated and die, but their...
Morphological Manifestations of Necrosis
Necrotic cells show different types of morphological appearance depending on the type of tissue and infection. In coagulative necrosis, cells become anucleated and die, but their...
pH Regulation in Cells
pH plays a critical role in maintaining normal cellular activities. It helps maintain the structure and function of various proteins, dictates the charge on cellular membranes, and is crucial for metabolic reactions inside the cell. Moreover, cells use the energy from the proton motive force to generate ATP.
Cytosolic pH
Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
Cytosolic pH
Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
Feedback Regulation of Calcium Concentration
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
The Effect of Aging on Tissues
Several body functions deteriorate with age. The external signs of aging are easily identifiable. For example, the skin becomes dry, less elastic, and thins out, forming wrinkles. The skin of the face begins to appear looser due to a decrease in the levels of elastic and collagen fibers in the connective tissue. Additionally, melanin production in the hair follicle decreases with age, resulting in gray hair. Moreover, the senses of sight and hearing decline, so glasses and hearing aids may...
Cellular Adaptation I: Introduction and Atrophy
Cells can adapt to environmental changes to maintain function and avoid injury, a process called cellular adaptation. Adapted cells exist in a reversible intermediate state with changes in size, number, phenotype, metabolism, or function. These responses help cells meet altered physiological or pathological demands; for example, enlargement of breast and uterine tissues during pregnancy. Early adaptations may enhance function, but persistent stress eventually causes tissue damage.Types of...
Cellular Injury IV: Necrosis
Necrosis is a form of irreversible cell death caused by severe injury such as ischemia, toxins, or trauma. Unlike programmed cell death, it is an uncontrolled, pathological process that typically provokes inflammation in surrounding tissues.Pathophysiologic ChangesNecrosis begins when cells sustain critical damage, leading to swelling of organelles, particularly mitochondria, and rapid ATP depletion. As energy levels decline, membrane ion pumps fail, leading to calcium influx and eventually,...


