Spermidine, a natural polyamine produced from putrescine and decarboxylated S-adenosylmethionine (dcSAM) by spermidine synthase, is a novel autophagy inducer and negatively modulates N-methyl-d-aspartate (NMDA).

Piribedil is a relatively selective dopamine (D2/D3) agonist with moderate antidepressant activity. It also has α2-adrenergic (α2A/α2C) antagonist properties.

Pirenzepine is an antimuscarinic agent which inhibits gastric acid secretion at lower doses than are required to affect gastrointestinal motility, salivary, central nervous system, cardiovascular, ocular and urinary functions.

Afloqualone (AFQ) is a quinazolinone family GABAergic drug with muscle-relaxant and sedative effects, showing the agonist activity at the β subtype of the GABAa receptor.

Flupentixol, an antipsychotic neuroleptic drug, is a powerful antagonist of both D1 and D2 dopamine receptors and also an alpha-adrenergic receptor antagonist.

Methacholine is a synthetic choline ester that acts as a non-selective muscarinic receptor agonist in the parasympathetic nervous system but has little effects on the nicotinic receptors.

Benactyzine hydrochloride is a centrally acting muscarinic antagonist. It is used as an antidepressant in the treatment of depression and associated anxiety.  

Sarpogrelate is a selective 5-HT2A antagonist with pKi values of 8.52, 7.43 and 6.57 for 5-HT2A, 5-HT2C and 5-HT2B receptors respectively.