Angiotensin III is a hormone that plays an essential role in regulating blood pressure. The word "Angiotensin" is spelled as /ænˌdʒaɪ.oʊˈtɛnsɪn/ in IPA phonetic transcription. The "ng" sound in the word is represented by the letter combination "ng," while the "o" sound is represented by the letter combination "io." The stress falls on the third syllable in the word, which is represented by a raised horizontal line under the letter "o." Overall, the spelling of Angiotensin III follows standard English language rules for word formation and pronunciation.
Angiotensin III is a peptide hormone that plays a significant role in regulating blood pressure and fluid balance within the body. It is a part of the renin-angiotensin system, which is a hormonal cascade involved in the regulation of blood pressure and salt-water balance.
Angiotensin III is derived from angiotensin II, which is produced when the enzyme renin acts on a plasma protein called angiotensinogen. Angiotensin II is then converted into angiotensin III through the action of an enzyme called angiotensin-converting enzyme (ACE).
Once formed, angiotensin III binds to specific angiotensin receptors found in various tissues, including blood vessels, heart, adrenal glands, and the brain. By binding to these receptors, angiotensin III constricts blood vessels, leading to an increase in blood pressure. Additionally, it stimulates the release of aldosterone from the adrenal glands, which promotes the reabsorption of sodium and water by the kidneys, further contributing to an increase in blood volume and pressure.
The overall effect of angiotensin III on the cardiovascular system is to increase blood pressure by narrowing blood vessels and promoting fluid retention. This hormone also has effects on other physiological processes, such as the release of vasopressin (antidiuretic hormone) from the pituitary gland, which helps regulate water balance and urine production.
In summary, angiotensin III is a peptide hormone that plays a crucial role in blood pressure regulation and fluid balance through its vasoconstrictive and fluid-retaining effects.
The word "angiotensin III" is a compound term combining two parts: angiotensin and III.
1. Angiotensin: The term "angiotensin" comes from the Latin word "angiotensio", which means "narrowing of vessels". It was coined by the Swiss physiologist Robert Tigerstedt and his student Per Bergman in 1898 when they discovered a substance in the blood that caused vasoconstriction (narrowing of blood vessels). They named it "angiotonin" (later angiotensin) because of its ability to constrict blood vessels.
2. III: The Roman numeral "III" represents the number 3. In the context of angiotensin, it indicates that angiotensin III is the third molecule in the angiotensin cascade.