(06) 3-22 Flashcards
Just read this slide
ANP from atrium, BNP from ventricle (counteract activity of angiotensin II)
(Hormonal (Humoral) Regulation of Circulation
(Renin-Angiotensin-Aldosterone System)
- regulates bp by mainly regulating what?
- AT II is also a potent what?
- blood volume
- vasoconstrictor
(REnin-Angiotensin-Aldosterone System in Long Term BP regulation)
- AT II directly affects kidneys to cause retention of what?
- AT II causes adrenal glands to secrete what? which doe s what?
- Is an auotmatic feedback system to keep BP regulated despite changes in what?
- salt and water
- adlosterone –> Na (and thus, H2O retention by renal tubules)
- dietary salt intake
this shows time course of different mechanims to control blood pressure
(Long-Term Blood PRessure Regulation)
- longer to become active - effective for long term - can it return arterial BP back to normal?
- Which mechanism is most important?
- if BP increases –> direct increase in renal output of what? leads to what? leads to?
- If BP is too low –> decrease in Na and H2O output –> ? —> ?
- yes
- renal-body fluid
- Na and H2O; decreased extracellular fluid and blood volume; decreased BP (pressure diuresis)
- fluid retention –> increased BP
(Renal - Body Fluid Mechanism)
- pressure at which equilibrium occurs can change –> affects what?
- shift in what?
- change in level of intake of what?
- long term BP level
- renal output curve
- salt and water
(Properties of the Heart)
1-4. what are the four
- do these properties occur without extrinsic innervation?
- Automaticity, rhythmicity - ability to generate electrical impulse (chronotropy)
- Conductiivty - ability to depolarize and conduct electrical impulse (dromotropy)
- Contractility - ability to shorten and do work (inotropy)
- Lusitropy - ability to relax and fill
- yes (although autonomic innervation can modify them)
she talked a decent amount about these valves on the right image
she does a whole hand routine that might be helpful 23:00 in 4/16 9:00 AM
(Cardiac Conduction System)
- composed of what?
(sinoatrial node - pacemaker of the heart)
- near what?
(Atrioventricular node)
- near what?
- 1 Av node conducts slowly - why is this good?
(Av bundle - budle of his)
- Av node to what?
(R and L bundle branches)
- endocardium
(Purkinje Fibers)
- penetrate into what?
- modified muscle cells
- cranial Vena cava and right auricle
- right side of intra atrial septum, ventral to coronary sinus
- 1 allows for filling of ventricles
- intra ventricular septum (goes through fibrous base)
- myocardium
- myocytes are most common
- purkinje fiber cells are big cells - conduct rapidly - good electrical conductivy
- AV node cells are smaller - makes for much slower conduction (same with SA node)
- Heart acts like a functional what?
- syncytium (acts like a single cell) - due to gap junctions
Cariac Innervation
two points she wants to make
- sympatheic nervous innervation goes to what part of heart?
- how about parasympathetic?
this is all we need to know about this
(we don’t need innervation for heart to function)
- Sa node, Av node, atrial and ventricular tissue (all over the heart)
- alot to SA node and AV, and a little to atrial tissue - but not to ventricles
(Cardiac Cell Electrophysiology)
(Cardiac action potential duration)
- much longer or shorter thatn APs of nerve and skeletal muscle?
(Cardiac Action potentials differ among different types of heart cells)
(Two main types of cardiac APs)
- fast response: what have these?
- slow response: what have these?
- longer
- atrial and ventricular muscle cells, and purkinje fibers
- sinus and A-V nodal cells
(Cadiac Cell Electrophysiology)
(Sarcolemma)
- maintains what?
- responds to depolarizing wave by doing what?
- at rest the sarcolemma is impermable or permeable to Na and Ca?
- At resting membrane potential, what is important in ion maintentance?
- During depolarization, controlled entry of ions through what?
(Conductance)
- permeability of the mebrane to what?
- conductance helps determeine what?
- ion gradients
- opening and closing specific ion channels (voltage-activated channels)
- impermeable (some background leakage of K out)
- Na, K-ATPase —> 2 K in, 3 Na out
- their specific voltage -activated channels
- a particular ion
- the rate of current flow
(Cell Membrane Potential)
- electrical and chemical forces important
- ions –> across sarcolemma only by some type of carrier: channel, exchanger, or pump - channel must be open
- Ion movement depends on what two things?
- electrical driving force (potential) and concentration gradient
(Resting Membrane Potential)
- maintained by what two things?
- passive outward K current
- Na/K ATPase activity (intracellular proteins contribute to negative intracelluar charge as well)
1-3. What are the three configurations?
- closed (“resting”)
- open (“activated”)
- inactivated (“recovering from activation”)
she talekd about this picture a decent amount
- Why is the inactivaiton state important?
- if you overstimulate a muscle you get tetany
- overal ionic conductance at a given time reflects what?
- K+ currents: what are two types of channels?
- the number of channels open
- voltage operated; ligand (G protein and non-G prtoin dependent) what she wants us to focus on is the fact that K going out of cell to bring it back to resting membrane potential
(“Fast Response” Action Potential)
- characteristic of what?
phase 0 = Na coming in
phase 1 = Ca in
phase 2 (plateau phase) = K out
phase 3 = repolarization phase
phase 4 = resting membrane potential
- working muscle, atrial and ventricular, purkinje cells
- subthreshold (A and B) = ?
- Threshold reached (C) –> ?
- local response
- regenerative response
(Vascular Action Potential)
- answer the question
if alot of sodium channels are still in recovery pahse - not enough sodium will be able to go thorugh channel therefore upstoke ins’t as rapid
(Refractory Period)
she got cut off here - so figure this out
