Ultrastructure of Myocardial Cells in the Right Atrium of Spontaneous Hypertension Rats.

Hypertension is the most common cardiovascular disease in China, which can seriously affect the heart, brain, kidney and other vital organs of the human body, and is the main cause of cardiovascular and cerebrovascular diseases and even death. Chronic hypertension can lead to remodeling of the right atrium, mainly due to factors such as pressure and volume overload of the right atrium and overactivation of neuroendocrine factors. It mainly includes cardiac remodeling and myocardial tissue remodeling. The purpose of this study was to observe the ultrastructure of myocardial cells in the right atrium of spontaneous hypertension rats. In this study, 10 12-week-old SHR rats were selected as the experimental group (SHR group), and WKY rats of the same age and sex were selected as the control group (WKY group, n = 10). Blood pressure was measured at the beginning and end of the 18-week trial. A section of the rat right atrium was taken for staining, and the percentage of the vascular wall area, the vascular lumen area (LA), and the vascular wall area of the heart wall were calculated by using the computer-assisted imaging system. The results showed that WKY's blood pressure remained at the normal level (106.65±6.55) mmHg. The blood pressure of SHR group increased from 8 weeks of age, and the systolic blood pressure of SHR8, SHR16 and SHR24 groups were (121.4±5.60), (204.7±5.60) and (226.45±6.60) mmHg, respectively, which were significantly higher than the WKY group of the same week (P < 0.05). In 30-week old SHR rats, the intima of the myocardial wall arterioles were significantly thickened and lumen decreased. This mechanism may be related to the imbalance between proliferation and apoptosis of medium smooth muscle cells. This paper introduces the characteristics of myocardial arteriole remodeling in SHR, which provides a basis for the study of hypertension and its vascular remodeling as well as the prevention and treatment of target organ damage. [ABSTRACT FROM AUTHOR]