PNU-120596 is a drug that acts as a potent and selective positive allosteric modulator for the α7 subtype of neural nicotinic acetylcholine receptors. It is used in scientific research into cholinergic regulation of dopamine and glutamate release in the brain.
PNU-181731 is a drug which acts as an agonist at serotonin 5-HT2receptors, with strongest binding affinity for the 5-HT2C subtype at 4.8nM, and weaker 5-HT2A affinity of 18nM. It has anxiolytic effects in animal studies with around one tenth the potency of alprazolam and no significant ataxia or other side effects noted.
PNU-99,194(A) (or U-99,194(A)) is a drug which acts as a moderately selective D3 receptor antagonist with ~15-30-fold preference for D3 over the D2 subtype. Though it has substantially greater preference for D3 over D2, the latter receptor does still play some role in its effects, as evidenced by the fact that PNU-99,194 weakly stimulates both prolactin secretion and striatal dopamine synthesis, actions it does not share with the more selective (100-fold) D3 receptor antagonists S-14,297 and GR-103,691.
In rodent studies, low doses of PNU-99,194 produce conditioned place preference (CPP) with no effect on intracranial self-stimulation (ICSS), whereas low doses of D3 agonists like 7-OH-DPAT inhibit ICSS behavior and cause conditioned place aversion (CPA). In contrast, high doses of PNU-99,194 produce CPA and inhibit ICSS, while high doses of 7-OH-DPAT result in the opposite. Paralleling this, low doses of PNU-99,194 and 7-OH-DPAT induce hyperactivity and hypoactivity, respectively, whereas the inverse is seen at high doses with both agents. These data indicate that the D3 receptor has biphasic effects on reward mechanisms and locomotor activity, likely due to opposing roles of autoreceptors versus postsynaptic receptors.
Verse 1: I became her lover, she became my lover. Had her heart broke, I was helping her recover. I became the man she knew she could rely on. Somebody to listen or shoulder to cry on. She was getting better, better she was getting. The more time spent, the more she would forget him. But then back around he seen that he started coming, and shes on the low taking phone calls from him. I thought that we were building something strong. He apologizes and now your gone. And I won't put up with this.
Pre-chorus: You wanna go. (Go.) Just hope you know. Baby your gonna be lonely, lonely again. Oh lonely, lonely. Go on go, go. Just hope you know. (Hey.) Baby your gonna be lonely, lonely again. Lonely, lonely again.
Chorus: Don't call me when your lonely again. When your lonely again, lonely again. Oh, sugga don't call me when your lonely again, when your lonely again. Lonely again. (Oh.)