Yohimbine act at which site presynaptic or postsynaptic ?
Yohimbine primarily acts as an antagonist at alpha-2 adrenergic receptors. These receptors are typically found in both presynaptic and postsynaptic sites in the central nervous system (CNS). Yohimbine’s antagonistic action on these receptors leads to an increase in noradrenaline release, resulting in various physiological effects.
In presynaptic sites, yohimbine’s blockade of alpha-2 adrenergic receptors prevents the negative feedback inhibition of noradrenaline release. This leads to increased noradrenergic activity in the synaptic cleft.
In postsynaptic sites, yohimbine’s antagonism of alpha-2 adrenergic receptors can enhance the postsynaptic response to noradrenaline, promoting increased excitability and neurotransmission.
Overall, yohimbine’s effects involve both presynaptic and postsynaptic actions due to its interaction with alpha-2 adrenergic receptors.