Renin. The most common cause of secondary hypertension is typically related to the kidneys. Since renin is often released in greater amounts with conditions like Renal Stenosis. Renal artery disease can cause of narrowing of the vessel lumen (stenosis). The reduced lumen diameter increases the pressure drop along the length of the diseased artery, which reduces the pressure at the afferent arteriole in the kidney. Reduced arteriolar pressure and reduced renal perfusion stimulate renin release by the kidney. This increases circulating angiotensin II (AII - most potent vasoconstrictor in the body) and aldosterone. Addendum: Angiotensin II is DEGRADED to a less effective vasoconstrictor call Angiotensin III -- therefore, not as effective. Glycogen has NO effect on BP Erythropoietin is released from the kidney to promote production of blood. Osteoblastosis is a bone disease commonly found in Rickets. Hope this helps.
Jill, Your answer is the overproduction of renin. This is because the heart and vasculature are regulated, in part, by neural (autonomic) and humoral (circulating or hormonal) factors. Neural mechanisms primarily involve sympathetic adrenergic and parasympathetic cholinergic branches of the autonomic nervous system. In general, the sympathetic system stimulates the heart and constricts blood vessels resulting in a rise in arterial pressure. The parasympathetic system depresses cardiac function and dilates selected vascular bed. There are several very important humoral mechanisms including circulating catecholamines, the renin-angiotensin system - when renin is released into the blood, it acts upon a circulating substrate, angiotensinogen, that undergoes proteolytic cleavage to form the decapeptide angiotensin I. Vascular endothelium, particularly in the lungs, has an enzyme, angiotensin converting enzyme (ACE), that cleaves off two amino acids to form the octapeptide, angiotensin II (AII), although many other tissues in the body (heart, brain, vascular) also can form AII - vasopressin (antidiuretic hormone), atrial natriuretic peptide, and endothelin. Each of these humoral systems directly or indirectly alter cardiac function, vascular function, and arterial pressure. The information provided here should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. I add a link containing details of this subject topic/topic100587305 Hope this helps matador 89
It has been quite a while since I graduated nursing school, but I think it would be the inhibition of angiotensin III. These enzymes are associated with the kidneys, which is a very important organ in regulating blood pressure. The others, best as I can recall, have nothing to do with the kidneys.
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