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Neural and Hormonal Regulation of Blood Pressure

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Neural and Hormonal Regulation of Blood Pressure Class 17/Lab 7: Neural and Hormonal Regulation of Blood Pressure 1. Discuss intrinsic (local tissue factors) and extrinsic (sympathetic nerves and hormones) regulators of arteriolar smooth muscle tone. Big picture idea is as follows: intrinsic, local factors regulate blood flow whereas extrinsic factors regulate blood pressure. 2. Relate principles of negative feedback to blood pressure regulation. Blood pressure regulation is one of the most important negative feedback mechanisms in the body. 3. Explain how a baroreceptor works i.e. what makes it depolarize, where it sends information to, what are the consequences of that information. 4. Describe the parts (receptor, sensory neuron, integrator, motor neuron, effector=target) of the baroreceptor reflex arc. 5. Discuss how neural (baroreceptors) and hormonal (RAAS) mechanisms work together to maintain BP. Explain the functions of aldosterone and angiotensin II. 6. Relate the electrical events represented by the ECG with the mechanical events represented by the pulse tracing. INTRINSIC TISSUE REMOVED FROM BODY MAINTAIN ITS Pre PERIES Smooth muscle ENDOTHELIUM VASOD c VASOCONSTRICTION e nn ENDOTHELIN T coz tu Oz 1. Discuss intrinsic (local tissue factors) and extrinsic (sympathetic nerves and hormones) regulators of arteriolar smooth muscle tone. Big picture idea is as follows: intrinsic, local factors regulate blood flow whereas extrinsic factors regulate blood pressure. EXTRINSIC NERVE STIMULATION Sws NE HORMONES ANGIOTENSIN II Smooth muscle NDOTHELLUM f 1 VASODILATION VASOCONSTRICTION Bz RECEPTOR NE 2 ADRENERGIC RECEPTOR Angiotensin I 2. Relate principles of negative feedback to blood pressure regulation. Blood pressure regulation is one of the most important negative feedback mechanisms in the body. BARO RECEPTOR 3. Explain how a baroreceptor works i.e. what makes it depolarize, where it sends information to, what are the consequences of that information. BARO RECEPTOR REFLEX ARC STIMULUS TBP C I SENSOR BAR RECEPTOR NEGATIVE 1 FEEDBACK SENSORY NEURON AFFERENTS I c i i EFFECTORS VASCULATURE Isms INE onRECEPTORS RESPONSE IBP 4. Describe the parts (receptor, sensory neuron, integrator, motor neuron, effector=target) of the baroreceptor reflex arc. Skip 5. Discuss how neural (baroreceptors) and hormonal (RAAS) mechanisms work together to maintain BP. Explain the functions of aldosterone and angiotensin II. HYDROSTATIC PRESSURE FLUID 1 GRAVITY BLOOD PRESSURE GRAVITY T BELOW THE HEART I ABOVE THE HEART STANDING PERSON T TOWARD FEET 6 TOWARD HEAD HYDROSTATIC PRESSURE INFLUENCES HOW BLOOD IS DISTRIBUTED 2. Relate principles of negative feedback to blood pressure regulation. Blood pressure regulation is one of the most important negative feedback mechanisms in the body. 3. Explain how a baroreceptor works i.e. what makes it depolarize, where it sends information to, what are the consequences of that information. 4. Describe the parts (receptor, sensory neuron, integrator, motor neuron, effector=target) of the baroreceptor reflex arc. HYDROSTATIC PRESSURE VARIES WITH POSITION SUPINE STANDING ARTERIES amunues J Tf VEINS EEN Distribution.EE sifnaz n PRESSURE If CAPS ARTERIOLES I I pooling OF BLOOD Dr Wu 2. Relate principles of negative feedback to blood pressure regulation. Blood pressure regulation is one of the most important negative feedback mechanisms in the body. 3. Explain how a baroreceptor works i.e. what makes it depolarize, where it sends information to, what are the consequences of that information. 4. Describe the parts (receptor, sensory neuron, integrator, motor neuron, effector=target) of the baroreceptor reflex arc. ORTHOSTATIC HYPOTENSION GETTING DIZZY OR PASSING OUT WHEN GETTING UP SUDDENLY FAILURE OF THE BAD RECEPTORS TO RESPOND Quickly WHEN STANDING TOO QUICKLY BLOOD POOLS to FEET Quickly compromise CARDIAC OUTPUT Urzco BECAUSE VENUOUS RETURN MOVED TOWARD FEET AGE RESTING BLOOD PRESSURE Blood VOLUME 2. Relate principles of negative feedback to blood pressure regulation. Blood pressure regulation is one of the most important negative feedback mechanisms in the body. 3. Explain how a baroreceptor works i.e. what makes it depolarize, where it sends information to, what are the consequences of that information. 4. Describe the parts (receptor, sensory neuron, integrator, motor neuron, effector=target) of the baroreceptor reflex arc. TIMING REFLEX US HORMONE NEURAL REFLEX FAST CHANGE 1W POSITION OR ACTIVITY HORMONE REFLEX Slow WhER TERM EFFECTS 2. Relate principles of negative feedback to blood pressure regulation. Blood pressure regulation is one of the most important negative feedback mechanisms in the body. 3. Explain how a baroreceptor works i.e. what makes it depolarize, where it sends information to, what are the consequences of that information. 4. Describe the parts (receptor, sensory neuron, integrator, motor neuron, effector=target) of the baroreceptor reflex arc. 2. Relate principles of negative feedback to blood pressure regulation. Blood pressure regulation is one of the most important negative feedback mechanisms in the body. 3. Explain how a baroreceptor works i.e. what makes it depolarize, where it sends information to, what are the consequences of that information. 4. Describe the parts (receptor, sensory neuron, integrator, motor neuron, effector=target) of the baroreceptor reflex arc. .
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