Cvs 2 - Part 1 Flashcards
Where are Alpha 1 receptors found
blood vessels (smooth muscles)
Where are alpha 2 receptors found
heart, pancreas, and kidneys; mostly insignificant
What do alpha 2 receptors do to the heart
causes a converse effect on the heart causing relaxation;
Where are beta 1 receptors found
Heart
What happens when beta 1 receptors are stimulated
if these receptors are stimulated, heart rate and contraction of the cardiac muscle is increased (vice versa)
Where are beta 2 receptors found
Bronchial musculature (lungs and airways);
What happens when beta 2 receptors are stimulated
if these receptors are stimulated the airways open up and breathing becomes less labored (eases the burden of breathing; especially witnessed in cases of Bronchial Asthma)
• What is the first major beta-blocker?
Propranolol; non-selective beta-blocker
When can propranolol be dangerous
And what does it do?
can potentially be dangerous in patients with Asthma due to its blocking of ALL beta receptors
What types of conditions is propranolol used in
used in over 1,000 conditions mainly related to increased heart rate
Who discovered propranolol
What did he win?
Scottish scientist James W. Black; won the Nobel prize in Medicine for this in 1988
• Denervation Atrophy
– interruption of the nerve connection to an organ or part
Auto-rhythmicity –
• generating rhythmic action potential independent of the nervous system;
• Cardiac Cell Membrane – what kind of unique channels does. It have
has unique channels called fast sodium channels
Cardiac tissue has what two characteristics
is self excitable and exhibits auto-rhythmicity
How are cardiac tissue cells joined
special junctions that are called intercalated discs. Intercalated discs are gap-junctions
What are gap junctions
neighboring cells are connected to each other via junctions that are shaped like bridges or tunnel
What is happening to the cells in a region of the heart when one cell is relaxed or excited
All cells same level of excitation or relaxation due to the presence of these gap junctions