Decrease in BP causes:
Ans: B (Dis-inhibition of vasoconstrictor center) Ref: Pal GK. Blood pressure and its regulation. In: Textbook of Medical Physiology. Ahuja Publishing House. 2011: 42: 324.Explanation:Reduction in BP is perceived by baroreceptors and less nerve traffic (signals) is sent to cardiac inhibitory center (CIc) (Less stimulation to CIc)There will be dis-inhibition of vasoconstrictor center (Vasomotor center) by GICIncreased VMC activity stimulates sympathetic activityBaroreceptor| BP -stimulation (stretch) of baroreceptors (carotid sinus & aortic arch) - through IX & X cranial nerve - stimulation of NTS - inhibition of VMC- | sympathetic discharges -| BP (| SBP by | CO and | DBP by | vasoconstriction) and also | HR| BP- less/no stimulation (stretch) of baroreceptors (carotid sinus & aortic arch) - through IX & X cranial nerve - less/no stimulation of NTS - dis-inhibition of VMC - | sympathetic discharges -|BP ( | SBP by | CO and | DBP by | vasoconstriction) and also | HR.Also, Refer Baroreceptor mechanism figure in the previous question's explanation.
Inhibition of vasoconstrictor center
Dis-inhibition of vasoconstrictor center
Increased stimulation of cardiac inhibitory center
Increased vagal stimulation
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