Quinapril effects on resistance artery structure and function in hypertension

Area of Science:

• Pharmacology
• Cardiovascular Biology
• Cell Biology

Background:

• Hypertension is associated with adverse cardiovascular remodeling and impaired vascular function.
• Angiotensin-converting enzyme inhibitors like quinapril are used to treat hypertension.
• Understanding the vascular effects of quinapril is crucial for managing cardiovascular disease.

Purpose of the Study:

• To investigate the effects of chronic quinapril treatment on blood pressure, vascular reactivity, and arterial structure in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats.
• To elucidate the cellular mechanisms, including apoptosis, underlying quinapril's vascular effects.

Main Methods:

• Adult male SHR and WKY rats received quinapril (10 mg/kg/day) for 10 weeks.
• Vascular structure was assessed using confocal and light microscopy.
• Vascular reactivity was evaluated using a pressure myograph system.
• Apoptosis in the mesenteric vessel wall was detected via TUNEL staining.

Main Results:

• Quinapril significantly reduced systolic blood pressure and ventricular weight in both SHR and WKY rats.
• Vascular remodeling, including reduced wall thickness and medial volume, was observed in quinapril-treated rats.
• Quinapril normalized contractile responses and improved relaxation in mesenteric arteries of SHR.
• An increased number of apoptotic smooth muscle cells was noted in the mesenteric arteries of both rat groups.

Conclusions:

• Chronic quinapril administration effectively lowers blood pressure and improves cardiac and vascular structure and function.
• Increased apoptosis of medial smooth muscle cells is a key mechanism contributing to quinapril-induced vascular structural improvements.
• Quinapril demonstrates beneficial effects on both hypertensive and normotensive rat models.