Mastering Blood Pressure Control

1. Internal variable to be maintained
2. Receptors sensitive to change in the variable
3. Afferent pathways from the receptors
4. An integrating center for the afferent inputs
5. Efferent pathways from the integrating center
6. Target effectors that alter their activities

The main baroreceptor locations are the walls of the aorta and the carotid artery.

The function of baroreceptors is to sense changes in blood pressure. They increase their firing rate when blood pressure increases and decrease their firing rate when blood pressure decreases.

<p>The purpose of nervous control of arterial pressure is to rapidly increase or decrease arterial pressure in response to different physiological demands.</p> Signup and view all the answers

<p>It is important to control blood pressure to maintain tissue perfusion across the whole body. If blood pressure is too low, blood flow to organs would fail, and if blood pressure is too high, there could be damage to vessels and organs.</p> Signup and view all the answers

<p>The primary purpose of baroreceptor reflex control is to reduce the minute-to-minute variations or arterial pulse.</p> Signup and view all the answers

<p>Cardiopulmonary baroreceptors sense central blood volume and their firing rate affects sympathetic and parasympathetic nerve activity to the heart and blood vessels.</p> Signup and view all the answers

<p>The Atrial reflex control of BP (Bainbridge Reflex) is a sympathetic-mediated reflex that increases heart rate and contractility in response to increased blood in the atria, preventing damming of blood in veins.</p> Signup and view all the answers

<p>The target effectors in the reflex control of blood pressure are the heart (controlled by sympathetic and parasympathetic nerves) and blood vessels (controlled by sympathetic nerves, which exert vasoconstrictor tone).</p> Signup and view all the answers

<p>The main points about the neuronal reflex mechanisms are that they exist to maintain blood pressure in the immediate/short term, they are integrated in the medullary cardiovascular control (MCVC) center, and they involve baroreceptors, efferent and afferent pathways, and target effectors.</p> Signup and view all the answers

<p>$\text{Stroke volume} \times \text{heart rate} = \text{cardiac output}$</p> Signup and view all the answers

<p>The Frank-Starling mechanism is the intrinsic mechanism of self-regulation in which an increase in end-diastolic volume (EDV) leads to an increase in the force of contraction.</p> Signup and view all the answers

<p>Preload refers to the venous pressure and venous return to the heart, specifically the end-diastolic pressure (EDP).</p> Signup and view all the answers

<p>Afterload refers to the pressure in the aorta or pulmonary artery.</p> Signup and view all the answers

<p>$\text{MABP} = \text{Diastolic pressure} + \frac{1}{3} \times \text{pulse pressure}$</p> Signup and view all the answers

<p>Stroke volume, speed of ejection of stroke volume, arterial compliance, factors affecting flow of a fluid through a vessel (viscosity, vessel length, vessel radius)</p> Signup and view all the answers

<p>The Poiseuille Equation is used to calculate the resistance to flow in a vessel. It takes into account blood viscosity, vessel length, and vessel radius.</p> Signup and view all the answers

<p>Arterial pressure = cardiac output x total peripheral resistance</p> Signup and view all the answers

<p>Mean arterial blood pressure (MABP) = Diastolic pressure + 1/3 pulse pressure. Systemic circulation: MABP = 120/75. Pulmonary circulation: MABP = 26/8.</p> Signup and view all the answers

<p>Cardiac output depends on venous return and can be intrinsically and extrinsically altered. Arterial pressure depends on cardiac output and total peripheral resistance.</p> Signup and view all the answers