Dobutamine is beta 1 agonist it increases the heart rate, can it produce hypotension as a reflex vagal stimulation?
The reflexes controlling the blood pressure are initiated from the baroreceptors: If ABP increases, the baroreceptors triggers reflex vagal stimulation which decreases the heart rate in an attempt to decrease the elevated ABP back to normal. If ABP decreases, the baroreceptors triggers reflex sympathetic stimulation which increases the heart rate in an attempt to increase the low ABP back to normal Dopamine is usually given to patients with compromised heart to stimulate it by direct action on beta-1 receptors. This tends to elevate the low ABP back to normal and does not initiate any reflex. Even in big doses which increase the ABP; the reflex vagal stimulation is masked by the direct stimulatory effect of dopamine on the heart. Read more…
