New bioactive angiotensins formation pathways and functional involvements

Area of Science:

• Biochemistry
• Physiology
• Pharmacology

Background:

• The Renin-Angiotensin System (RAS) is a key hormonal system.
• Recent research identifies new biologically active angiotensins derived from angiotensin II.
• Understanding these fragments' roles is crucial for cardiovascular and neurological health.

Purpose of the Study:

• To review current knowledge on circulating and tissue RAS.
• To present formation, mechanisms, and actions of novel angiotensins.
• To highlight the role of angiotensin IV in memory and Alzheimer's disease, and angiotensin (1-7) as a vasodilator.

Main Methods:

• Review of enzymatic pathways for synthesis and inactivation of angiotensin metabolites.
• Presentation of physio-pharmacological actions of angiotensin III, IV, and (1-7).
• Experimental investigation of angiotensin (1-7) and angiotensin II interactions in rat thoracic aorta.

Main Results:

• Angiotensin IV shows functional involvement in cerebral memory and neurodegenerative processes.
• Angiotensin (1-7) exhibits vasodilating effects, counteracting angiotensin II's vasoconstriction.
• Experimental data reveal biphasic, dose-dependent effects of angiotensin (1-7) in rat aorta, involving nitric oxide, kinins, and prostaglandins.

Conclusions:

• Angiotensin II fragments (III, IV, 1-7) possess distinct physiological roles.
• Angiotensin (1-7) acts as a counterbalance to angiotensin II, influencing cardiovascular function.
• Further research into RAS fragments is essential for understanding and treating cardiovascular and neurological disorders.