This question is essentially asking what happens to sympathetic and parasympathetic efferents in the setting of hypovolemia/dehydration. In this setting, there would be lower blood pressure and thus this would cause reduced firing of the carotid baroreceptors, ultimately leading to feedback which stimulates the sympathetic nervous system (to increase heart rate and cause peripheral vasoconstriction in order to compensate for hypovolemia) while also inhibiting the parasympathetics.
What I don't get is that the anterior hypothalamus is responsible for cooling and this involves the parasympathetic nervous system. So, how is the parasympathetic nervous system not active in this person as well?
thatmdI also got this one wrong because I was also thinking it was a heat stroke question. But I think because we were not actually given his body temperature (>40C for heatstroke), we need to focus on the fact that this dude was running a marathon on a "hot day" without adequate hydration as evidence by his low BP. +1
submitted by โcassdawg(1780)
This question is essentially asking what happens to sympathetic and parasympathetic efferents in the setting of hypovolemia/dehydration. In this setting, there would be lower blood pressure and thus this would cause reduced firing of the carotid baroreceptors, ultimately leading to feedback which stimulates the sympathetic nervous system (to increase heart rate and cause peripheral vasoconstriction in order to compensate for hypovolemia) while also inhibiting the parasympathetics.