Record: Normal ECG and Arterial Blood Pressure
Discussion: Explain the terms
"systolic" and "diastolic"; also, how blood pressure is related
to heart rate, stroke volume, and peripheral resistance. Discuss the major
neurocirculatory reflexes important in the short-term regulation of blood
pressure. Give data from record.
Section B -
Records: 1) Effect of ACh
2) Effect of Atropine followed by ACh
Discussion: Mention the types
and loci of cholinergic receptors associated with the
circulatory system and how each responds to exogenous ACh to bring about
the expected changes in heart rate and blood pressure. Describe the action
of atropine, and tell which of the previously mentioned receptors are affected.
Explain which cholinergic receptors can still respond to exogenous ACh
in the
atropinized animal to affect blood pressure. Support with data from record.
Section C -
Record: Effect of Epinephrine
Discussion: Discuss the adrenergic
receptors (location and type) which may influence
heart rate or blood pressure, and how each affected the observed response
to
infusion of epinephrine. Support with data from record.
Section D -
Record: 1) Effect
of clamping below the Carotid Sinus
2) Effect of Medullary Ischemia
Discussions:
1) Carotid sinus reflex - completely discuss the physiology
of this
reflex, naming the nerves involved in the afferent portion, and
the areas of the CNS which are involved. How does
constricting the carotid bring about the expected change in
systemic blood pressure? Support with data from record.
2) Response to Medullary Ischemia - Describe the CNS
area
involved and the changes in blood supply and blood content
which trigger the expected response. How is the expected
change in blood pressure brought about? Give data from record.