相关实验视频
Updated: Jun 26, 2026

04:39
Monitoring Gut Acidification in the Adult Drosophila Intestine
Published on: October 11, 2021
概括
高胆固醇饮食增加了子动脉样硬化病变中的血腺素3,5-单酸盐 (循环AMP) 和循环AMP水平. 其他器官没有显著变化,表明动脉样硬化局部影响.
科学领域:
- 生物化学 生物化学
- 心血管科学 心血管科学
- 细胞生物学 细胞生物学
背景情况:
- 高胆固醇饮食是动脉样硬化的一个已知的危险因素.
- 氨酸3,5-单酸盐 (循环AMP) 是一个关键的第二信使,参与各种细胞过程.
研究的目的:
- 调查子中高胆固醇摄入量与循环AMP水平之间的关系.
- 为了确定是否升高的循环AMP局部化到动脉样硬化病变.
主要方法:
- 子被养高胆固醇饮食.
- 测量了血胆固醇和循环AMP水平.
- 量化了大动脉内膜 (损伤和非损伤区域) 和其他器官中的循环AMP含量.
主要成果:
- 在高胆固醇饮食中的子中,血周期性AMP与血胆固醇同时显著增加.
- 大动脉的动脉硬化病变区域显示,与非病变区域和对照大动脉相比,周期性AMP含量显著更高.
- 心脏,肝脏,骨肌肉和腹膜周期性AMP水平保持不变.
结论:
- 循环AMP的升高与子的高胆固醇和动脉样硬化有关.
- 循环AMP的增加局部化到子大动脉中的动脉样硬化病变.
- 胆固醇诱导的循环AMP变化似乎特异于受到动脉样硬化影响的血管组织.
相关概念视频
What is Monogastric Digestion?
The human body contains a monogastric digestive system. In a monogastric digestive system, the stomach only contains one chamber in which it digests food. Several other animal species also have monogastric digestive systems, including pigs, horses, dogs, and birds. This chapter, however, focuses on the human digestive system.
Stomach pH Regulation
The human body carefully regulates the internal pH of different organs to maintain homeostasis. For example, while the blood plasma maintains a neutral pH of 7, the stomach lumen has an acidic pH of 1.5 - 3.5. The low pH of stomach lumen helps kill pathogens in the food and break down complex food molecules.
The acid-secreting gastric mucosal epithelial cells (parietal cells) lining the stomach lumen maintain the low pH in the lumen. Numerous ion transporters and channels on these parietal...
The acid-secreting gastric mucosal epithelial cells (parietal cells) lining the stomach lumen maintain the low pH in the lumen. Numerous ion transporters and channels on these parietal...
Protein Absorption
Proteins in the gastrointestinal tract typically come from food, but they can also originate from disintegrated cells or secreted enzymes. In the stomach, the enzyme pepsin breaks down these proteins into polypeptides. The fragments then move into the duodenum as a semi-fluid mass called chyme. Pancreatic proteases, such as trypsin and chymotrypsin, and intestinal brush border enzymes like carboxypeptidases further dismantle the polypeptides into tripeptides, dipeptides, and free amino acids.
Renal Regulation of Acid-Base Balance
Metabolic reactions in the body produce nonvolatile acids, such as sulfuric acid, which generate an acid load of approximately 1 mEq of H+ per kilogram of body weight daily. Excreting H+ in the urine is essential to balance this acid load.
In the kidneys, cells within the proximal convoluted tubules (PCT) and the collecting ducts secrete hydrogen ions (H+) into the tubular fluid. Specifically, in the PCT, Na+/H+ antiporters secrete H+ while reabsorbing Na+.
However, the intercalated cells in...
In the kidneys, cells within the proximal convoluted tubules (PCT) and the collecting ducts secrete hydrogen ions (H+) into the tubular fluid. Specifically, in the PCT, Na+/H+ antiporters secrete H+ while reabsorbing Na+.
However, the intercalated cells in...
Amino Acid Catabolism
Microorganisms rely on proteins as an essential carbon and energy source, particularly in environments with limited polysaccharides or lipids. However, proteins are too large to cross the plasma membrane unaided, necessitating enzymatic degradation. Microbes secrete extracellular proteases and peptidases that hydrolyze proteins into peptides, which can then be transported across the membrane. Once inside the cell, intracellular proteases degrade these peptides into free amino acids, which...
Microbiota of the Stomach and Small Intestine
The human gastrointestinal (GI) tract is characterized by distinct physicochemical conditions that shape its microbial communities. Among these, the stomach presents a particularly challenging environment for microbial colonization due to its highly acidic pH, ranging from 1 to 3. This extreme acidity effectively limits microbial density. However, certain acid-tolerant microorganisms are capable of surviving in this niche. Notably, Helicobacter pylori can colonize the gastric mucosa,...

