Its main role is to regulate salt and water in the body, thereby affecting blood pressure – but that isn’t the only role played by Angiotensin II in our bodies.īesides being a potent vasoconstrictor, Angiotensin II also exerts proliferative, pro-inflammatory (causing inflammation) and pro-fibrotic activities. It causes increases in blood pressure, influences renal (kidney) tubuli to retain sodium and water, and stimulates Aldosterone – Aldosterone is a steroid hormone secreted by adrenal glands. Angiotensin II, a peptide hormoneĪngiotensin II is the main effector molecule of the RAS. Angiotensin I does not appear to serve much other function, aside from acting as a chemical precursor to Angiotensin II, which affects multiple systems in our bodies. Renin cleaves angiotensinogen, forming Ang I that in turn is converted to Ang II by ACE. I will only mention the first two angiotensins in any detail for the purpose of this article. As it passes in the bloodstream through the lungs and kidneys, it is further metabolized to produce angiotensin II by the action of angiotensin-converting enzyme. This form of the hormone is not known to have any particular biological function in itself but, is an important precursor for angiotensin II. This is then broken up by renin, an enzyme produced in the kidney, to form angiotensin I. The liver creates and releases a protein called angiotensinogen. This local system has been shown to be responsive to various stimuli of physiological and pathophysiological importance and we continue to discover new associated systemic dependencies. Studies have shown that numerous tissues and organs contain their own locally generated angiotensin products. We understand the basic mechanisms underpinning the RAS, its component parts and some, but not all, of the systems many interactions and dependencies.įor instance, we have known for decades about the role angiotensin II (see below) plays in hypertension, but only recently discovered its influence on inflammation. The RAS is an incredibly intricate system that impacts our entire physiology and, like much of our biology, requires a delicate balance to function effectively. These hormones, and the way they are activated, are what we refer to as the renin angiotensin system or RAS. The are five different forms of angiotensin and these are denoted by Roman numerals, angiotensin I through IV. We’ve known about RAS for more than a 100 years now, but understanding the intricacies of how it works has only really been possible in the last three decades, with the discovery of several novel components, including genes like ACE and ACE2. The renin–angiotensin system or RAS is a major regulator of blood pressure homeostasis – homeostasis refers to a state of balance among all the body systems needed for the body to survive and function correctly. Grasping these basics is key to following the argument that unfolds below. The discovery of ACE2, RAS and moreĪ little biology first before we launch into the meat of the article as I will use certain abbreviations repeatedly throughout the piece. Please note that much of the research quoted here predates the pandemic, for obvious reasons. This article is an effort to explore the potential answers. I have none of these biases my motivation is to seek answers to this question – or raise other questions. I am not a virologist, but that, in some ways, may offer me a perspective that is distanced and more objective than the professionals who are overly invested in one school of thought or another. What follows is the result of many hours spent circling the forest to get the measure of the trees. Saving lives continues to be the primary mission of medicine. It is perhaps the most urgent question of our generation based on the global scale of vaccine deployment. Irrespective of the conclusions we arrive at, answering this question will save lives. Right now, it is the only question science should be focused on, especially as more treatments are developed and we expand mRNA-based Covid vaccines to healthy children. WHY? What are the clinical reasons these vaccines cause death in some people?Ĭould the deaths arising from vaccination simply be ascribed to poor science, a flawed understanding of the associated mechanisms of action of ACE2 and the RAS pharma has targeted with vaccine produced protein? There has to be a pharmacological explanation for what we see unfolding around us in real-time. The only one that really matters from a human and scientific perspective. While we immerse ourselves in a mire of questions relating to motives, gain of function and more, we lose sight of the real question we should be asking. That is no longer a debatable question, it is fact. Then we started questioning if the vaccines we had produced were contributing to that toll. We knew that Covid was fatal to some people.
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