Detectable fall in blood pressure occurs in
Sympathetic stimulation
Inhibition of VMC
Disinhibition of VMC
Stimulation of vagal centre
Baroreceptor stimulation results in the activation of two mechanisms.
1.    Stimulation of cardiovagal inhibitory centre- Nucleus ambiguous- Leads to Bradycardia.
2.    Inhibition of vasomotor centre- Rostral ventrolateral medulla- Leads to decreased BP.