<em>In Vitro</em> Intraluminal Gel Infusion: An Advanced Approach for Microscopic Analysis of Human Resistance Arteries

Resistance arteries, which include small arteries and arterioles, play essential roles in regulating blood pressure and tissue perfusion. Dysfunction in these arteries can lead to various cardiovascular conditions such as hypertension, atherosclerosis, and heart failure, as well as neurovascular conditions. The examination of human resistance arteries is crucial for understanding cardiovascular disease mechanisms and developing targeted therapeutic strategies. This study presents an innovative method for preparing isolated human resistance arteries by infusing a tissue-stabilizing gel into the lumen, preserving their native architecture and cellular integrity. Human omental tissues were obtained from patients undergoing abdominal surgeries, and small resistance arteries (100-300 µm in diameter) were isolated by careful micro-dissection. The arteries were then cannulated, pressurized in a culture myograph chamber, and fixed with 10% neutral buffered formalin. A tissue-stabilizing gel was infused into the lumen of the cannulated artery, which was allowed to solidify to preserve the three-dimensional structure. Histological, immunohistochemical, and gene expression analyses were performed to assess the preservation of the arteries. Histological sections revealed the well-preserved structural integrity and natural architecture of the arteries, maintaining well-defined endothelial and smooth muscle layers. Immunohistochemical staining showed distinct localization of markers such as CD31 and α-smooth muscle actin. In situ hybridization revealed specific gene expression patterns, providing insights into the molecular mechanisms. This advanced method of intraluminal gel infusion offers significant advantages, enabling advanced imaging and comprehensive analysis of arterial structure, remodeling, and cellular interactions in both healthy and diseased states. This method has the potential to improve clinical diagnostics and therapeutic strategies for vascular diseases, thereby providing a valuable tool for advancing vascular biology research.