Arterial Blood Pressure / RAAS

Sphygmomanometer

Inflatable cuff plus pressure gauge and stethoscope for manual BP

Systole, cannot

Cuff inflated

• Stopping arterial blood flow to measure __

• Sound __ (can/cannot) be heard from stethoscope over brachial artery

Korotkoff, pulsatile

Compressed artery - manual

• __ sounds only present here and created by __ blood flow thru compressed artery

• Cuff pressure between 80 - 120 mmHg

Diastole, silent

• Cuff deflated

  • Promoting full arterial blood flow to measure __

  • Blood flow is __ (loud/silent) as artery is no longer compressed

Ang II levels (B)

 In a severely dehydrated hypotensive individual, what is likely to be elevated compared to normal?

A) Firing rate of carotid baroreceptors

B) Circulating Ang II levels

C) ANP release

After, cardio

A higher __load from hypertensive crises can lead to __megaly

Intake, loss

Blood volume is determined by fluid __ and fluid __

Kidneys, dilute, concentrated, Na+, H2O

__ (organ) regulate how much water is conserved

• Control urine concentration

  1. Overhydrated - Lots of __ urine

  2. Dehydrated - __ urine

• Regulate reabsorption of __ and __ molecules

Conserve

The kidneys can only __ volume and cannot restore lost volume/fluid

Insufficient, excess, diarrhea, vomiting, sweating, hemorrhage

Blood volume disturbances - __ fluid intake, __ fluid intake, __ (GI), __ (GI), excessive __ (ANS), __ (bloody)

Venous, high, reservoir, poor

• Blood distribution is influenced by __ compliance

  • Veins - have __ compliance and function as a volume __

  • Arteries - have __ compliance, serve a fraction of total blood volume

Constriction, compliance, preload, stroke volume, cardiac output

Decrease in mean arterial pressure

• Increase sympathetic __ of veins

• Decrease venous __

• Increase venous return (__) and thus __ __

• Increase __ __ via Frank-Starling

Output, peripheral, compliance, water, salts, thirst, salt

3 targets of arterial pressure regulation

(1) Cardiovascular System - Alter cardiac __, __ resistance, and venous __

(2) Kidneys - Alter retention/excretion of __ and __

(3) Physiologic Behavior - Alter __ and __ appetite

Baro, mechano, carotid sinus, chemo, carotid bodies

Arterial __receptors sense stretch of artery wall via __receptor action

• These are located in the __ __ (wall of blood vessel)

Arterial __receptors detect CO2 and O2 levels

• These are located in the __ __

Pressure, baroreceptors, afferent, medulla, 90, efferent, heart, vessels, cardiac, peripheral

Arterial baroreceptor negative feedback loop

• Regulated variable = Blood __

• Sensor = __ in carotid arteries and aortic arch

• Input signal = Sensory __ nerves

• Control center = cardiovascular center in __

• Error detector = set point around __ mm Hg that resets over time

• Output signal = Parasympathetic and sympathetic __ nerves, epinephrine

• Effectors = __ and blood __

• Controlled variables = __ output and total __ resistance

Renin-angiotensin-aldosterone system

RAAS

Renin, low

Juxtaglomerular (JG) cells in kidney release __ in response to __ blood pressure

Afferent, Na+, sympathetic

Factors increasing renin release

• Decreased pressure in renal __ arterioles

• Decreased __ flowing thru distal convoluted tubule

• Increase __ NS (ANS) activity

Angiotensinogen, Ang I, ACE, Ang II

• Renin converts __ to __

• The enzyme __ then converts Ang I to __

Aldosterone, vasoconstriction, H2O, Na+, sympathetic

• Ang II can lead to adrenal cortex to release __ (increase blood pressure)

• Ang II can lead to __ of vascular smooth muscle (increase blood pressure)

• Ang II can lead to increased __ and __ reabsorption by kidney (increase blood pressure)

• Ang II can lead to increased __ outflow from the central NS (increase blood pressure)

Sympathetic, renin, Ang II

Increased __ NS outflow from the central NS by Ang II will stimulate __ release and thus conversion to __

• A (+) feedback mechanism

Aldosterone, reabsorption, excretion

__ is a steroid hormone that stimulates __ of salty water in kidney and stimulates K+ __ in urine

Na+, renal epithelial, water, Na+/K+ ATPase

Aldosterone

• Na+ reabsorption - Increases activity and expression of __ channels and NA+/K+-ATPase in __ __ cells

• __ follows Na+ solute

• Stimulates K+ excretion in urine (via __ __)

MAP, hyperkalemia

Aldosterone release is stimulated by:

low __ (Ang II → aldosterone)

and __ (ion abnormality)

osmolarity, dehydration, low, high

Aldosterone release is inhibited by:

high __

and __ (means a __ blood volume and __ osmolarity)

independently

Water and Na+ reabsorption can be regulated __ in the kidney

ADH, nighttime

Angiotensin II can have hypothalamus/ posterior pituitary gland release __

• Highest time of day this hormone is released - __

Vasopressin (ADH)

Anti-diuretic hormone

Decreased, increased, constriction, reabsorption, pressure, volume

Outcomes of ADH

1. Baroreceptors detect __ blood pressure or osmoreceptors detect __ osmotic pressure

2. Vaso__ of blood vessels OR increased __ of water by kidneys done by ADH

3.  Increased blood __ OR increased blood __

275-295

Normal set point of osmolarity is __-__ mOsm/L

Aquaporins, apical

ADH increases renal water reabsorption

• Inserts stored __ (channels) into the __ (basal/apical) membrane → “membrane recycling”

Atria, ventricles, cavae, arteries

Cardiopulmonary baroreceptors (different from arterial/carotid s)

are located in walls of the __ and __, venae __, and pulmonary __

ANP, BNP

Stretch of cardiopulmonary baroreceptors stimulates release of __ from atria/ventricles and __ from only ventricles

Venous, cardiopulmonary, ANP, kidneys, hypo, adrenal, excretion, dilation, ADH, aldosterone

Cardiopulmonary baroreflex control loop

• Regulated variable = __ volume

• Sensor, control center = __ baroreceptors

• Output signal = __ (hormone)

• Effectors = __, vasculature, __thalamus, __ cortex

• Controlled variables = Increase Na+ and H2O __, increase vaso__, decrease __ release, decrease __ release

• Goal is lower bp