###### Created: 2024-01-13 12:12 ###### Areas & Topics: #medicine #physiology ###### Note Type: #permanent ###### Connected to: [[Systemic Arterial Blood Pressure - Medical Sciences, Third Edition]] - They Bayliss effect is the effect seen when the blood vessels respond to stretch - It is called the Bayliss effect because it was discovered by Sir William Bayliss in 1902 ### Mechanism 1. [[Arteries]] and [[Arterioles]] contain stretch receptors on their endothelium. 2. When blood pressure is raised, these stretch receptors become activated due to distension of the vessel walls. 3. This then activates myocytes (muscle cells) in the walls of the vessels to constrict (this response is known as the Bayliss Effect) 4. The importance of this is that because these receptors exist locally in the blood vessels and activate the myocytes individually, this response doesn't need external input to occur (i.e. signals don't need to take all the time to travel through the nervous system to respond to blood pressure changes). 5. This means that the vessels can respond to blood pressure changes more quickly, constricting and lowering the blood pressure going into vessels further along and thereby autoregulating (keeping blood flow and pressure constant) in all the microvasculature (e.g. [[Capillaries]], sinusoids etc.) N.B. Autoregulation of the microvasculature is especially important because if central blood pressure changes continued downstream to the smallest vessels, the sudden pressure changes would likely damage the vessels or cause them to burst. ![[9F7oiwH.webp]] ### Resources https://en.wikipedia.org/wiki/Myogenic_mechanism#Bayliss_effect