Exam 18: Regulation of the Heart and Vasculature

A 24-year-old man is seen for a routine physical examination.At rest,his blood pressure is 120/80 mm Hg and his heart rate is 75 beats/minute.He is advised to begin an exercise program.When he returns 3 months later,his heart rate has decreased to 50 beats/minute (asymptomatic).Which of the set of values below would you expect to observe in this patient at rest in comparison with those 3 months ago?

During a cardiovascular examination,a patient has a resting heart rate of 65 beats/minute and a blood pressure of 100/70 mm Hg in the supine position.In the upright position at steady state,the patient's heart rate is 74 beats/minute,and the blood pressure is 105/70 mm Hg.One physiological change that occurred in the patient as a result of assuming an upright position is:

The myogenic mechanism for autoregulation of vascular smooth muscle tone:

During a cardiovascular examination,a patient has a resting heart rate of 65 beats/minute and a blood pressure of 100/70 mm Hg in the supine position.In the upright position at steady state,the patient's heart rate is 74 beats/minute,and the blood pressure is 105/70 mm Hg. Agents that increase intracellular cyclic adenosine monophosphate (cAMP),such as β-adrenergic agonists,have a potent vasodilator effect by: