Bp Homeostasis

• What is blood pressure?

  The pressure blood exerts on arterial walls
• What is the formula for blood pressure?

  BP = CO x TPR
• How is cardiac output calculated?

  CO = SV x HR
• What does TPR stand for in blood pressure regulation?

  Total Peripheral Resistance
• What is systolic blood pressure?

  Peak pressure during cardiac contraction
• What is diastolic blood pressure?

  Minimum pressure when the heart is relaxed
• What are the normal ranges for systolic and diastolic blood pressure?

  90-120 mmHg and 60-80 mmHg
• What are the components of blood pressure regulation?

  • Long-Term Renal/Hormonal Regulation
  • Short-Term Neural Control
• What system determines long-term blood pressure regulation?

  The renin-angiotensin-aldosterone system
• How is short-term blood pressure control achieved?

  Through cardiovascular centers and baroreceptor stimulation
• What do baroreceptors respond to?

  The pressure caused by the presence of blood
• What happens if blood pressure drops suddenly?

  Two problems confront the pressure control system
• What is the first problem the pressure control system faces when blood pressure drops?

  To return arterial pressure to a survivable level
• What is the second problem the pressure control system faces after a drop in blood pressure?

  To return blood volume to its normal level
• What are the components of the baroreceptor reflex?

  • Cardioaccelerator center
  • Cardioinhibitor center
  • Vasomotor center
• Where are baroreceptors located?

  In the medulla oblongata
• What does the cardioaccelerator center do?

  Stimulates cardiac function via sympathetic stimulation
• What is the role of the cardioinhibitor center?

  Slows cardiac function via parasympathetic stimulation
• What does the vasomotor center control?

  Vessel tone and contraction of smooth muscle
• How do changes in vessel diameter affect blood pressure?

  They affect peripheral resistance, pressure, and flow
• What happens when mean arterial pressure (MAP) increases?

  Baroreceptors fire more often
• What happens when mean arterial pressure (MAP) decreases?

  Baroreceptors fire less often
• What is the process of how baroreceptors work?

  1. Stretch on carotid sinus baroreceptors
  2. Firing rate of carotid sinus nerve increases/decreases
  3. Parasympathetic/sympathetic activity adjusts
  4. Heart rate and contractility change
  5. Total peripheral resistance adjusts
  6. Arterial pressure restored to normal