2-(1-Piperazinyl)pyrimidine

2-(1-Piperazinyl)pyrimidine is an orally effective α₂-adrenoceptor antagonist and 5-HT1A receptor agonist. 2-(1-Piperazinyl)pyrimidine is an in vivo metabolite related to buspirone. 2-(1-Piperazinyl)pyrimidine modulates excitatory synaptic transmission in the hippocampus and the release of monoamine transmitters such as norepinephrine and 5-HT by blocking α2-adrenoceptor and activating 5-HT1A Receptor. 2-(1-Piperazinyl)pyrimidine is used in research on psychiatric disorders such as anxiety and depression^{[1][2][3][4][5]}. In Vitro:2-(1-Piperazinyl)pyrimidine (0.1-1 μM; 10 min) antagonizes the inhibition of [³H]NA (pA₂ = 6.8) and [³H]5-HT (pA₂ = 7.3) release by α₂-adrenoceptors in rat cerebral cortex synaptosomes^[1]. In Vivo:2-(1-Piperazinyl)pyrimidine (0.5-2 mg/kg; p.o.; single administration; measured 40 min after dosing) dose-dependently antagonizes the inhibition of gastrointestinal transit in the Clonidine hydrochloride (HY-B0409A)-induced rat model of delayed gastrointestinal transit^[2].
2-(1-Piperazinyl)pyrimidine (0.5-4.0 mg/kg; s.c.; single administration; tested 30 min after administration) exhibits significant anxiolytic effects in the rat drinking conflict test model[3].
2-(1-Piperazinyl)pyrimidine (0.25-4 mg/kg; s.c.; single administration; model-inducing drug injected 30 min after administration) antagonizes pupil dilation in the Clonidine (HY-12721)-induced rat mydriasis model^[3].
2-(1-Piperazinyl)pyrimidine (0.063-0.5 mg/kg; s.c.; single administration; modeling drug injected 30 min after administration) reverses the decrease in locomotor activity in the Clonidine-induced hypokinesia model in rats^[3].
2-(1-Piperazinyl)pyrimidine (0.25-1 mg/kg i.p.; single administration; continuous monitoring for 60 min) transiently reduces the amplitude of field excitatory postsynaptic potentials in the hippocampal CA1 region in a rat hippocampal electrophysiological recording model^[5].
2-(1-Piperazinyl)pyrimidine (5 μg; intrahippocampal microinjection; single administration; continuous monitoring for 15-20 min) also exerts a transient inhibitory effect on excitatory synaptic transmission in the rat hippocampal electrophysiological recording model^[5].

2-(1-Piperazinyl)pyrimidine (0.25 mg/kg; i.p.; once daily; for 9 consecutive days, with monitoring from day 1 to 14) persistently decreases basal excitatory synaptic transmission and produces tolerance to acute administration in a rat hippocampal electrophysiological recording model^[5].