Uncontrolled diabetes with underlying structural changes in the atrioventricular node
Issued Date
2023-01-01
Resource Type
ISSN
07179367
eISSN
07179502
Scopus ID
2-s2.0-85171179411
Journal Title
International Journal of Morphology
Volume
41
Issue
4
Start Page
1027
End Page
1035
Rights Holder(s)
SCOPUS
Bibliographic Citation
International Journal of Morphology Vol.41 No.4 (2023) , 1027-1035
Suggested Citation
Plaengrit K., Lanlua P., Niyomchan A., Sricharoenvej S. Uncontrolled diabetes with underlying structural changes in the atrioventricular node. International Journal of Morphology Vol.41 No.4 (2023) , 1027-1035. 1035. doi:10.4067/S0717-95022023000401027 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/90146
Title
Uncontrolled diabetes with underlying structural changes in the atrioventricular node
Author(s)
Author's Affiliation
Other Contributor(s)
Abstract
Diabetic cardiomyopathy, characterized by diabetes mellitus (DM) -induced cardiac muscular abnormalities, is a strong inducer of impaired cardiac contraction and arrhythmia. Atrioventricular block, a serious type of arrhythmia resulting from interruption of cardiac impulse conduction via the atrioventricular node (AVN), frequently occurs among diabetic patients. However, details of structural changes in AVN in DM remain poorly explained. Here, this study defined the effects of DM on the morphological remodeling of the AVN in male Sprague Dawley rats induced by intraperitoneal injection of streptozotocin (60 mg/kg body weight). At 24 weeks, the pathological changes in the AVN were assessed by light microscopy (LM) and transmission electron microscopy (TEM). Under LM, the AVN in diabetic rats became a less compact mass and exhibited the intracellular vacuolation. The nodal cells were more varied in sizes with the absence or shrinkage of nuclei and clear cytoplasm compared to the control. The collagen content significantly increased in relation to the presence of myofibroblasts. Consistent with LM, TEM images of the diabetic nodal cells revealed several signs of cell damage, such as mitochondrial changes, deterioration of cell organelles, gap junction internalization, and cell separation. Furthermore, changes in AVN innervation, evidenced by damaged Schwann cells and axons, were also found. These results indicated alterations in important components in the AVN during diabetic condition, which may lead to the impairment of electrical conduction, causing abnormal cardiac functions in diabetic patients.