Unlike stimulants such as amphetamine, which release a flood of monoamine neurotransmitters in an uncontrolled manner, (–)-PPAP instead only increases the amount of neurotransmitters that get released when a neuron is stimulated by receiving an impulse from a neighboring neuron.[11][5] Both amphetamine and (–)-PPAP promote the release of monoamines; however, while amphetamine causes neurons to release neurotransmitter stores into the synapse regardless of external input, (–)-PPAP does not influence the pattern of neurotransmitter release and instead releases a larger amount of neurotransmitters than normal.[11][5]
PPAP and selegiline are much less potent than BPAP as MAEs.[3][10] Whereas PPAP and selegiline are active at doses of 1 to 5mg/kg in vivo in rats, BPAP is active at doses of 0.05 to 10mg/kg.[3] BPAP is 130times as potent as selegiline in the shuttle box test.[1] In contrast to BPAP however, the MAE effects of PPAP and selegiline are not reversed by the BPAP antagonist3-F-BPAP.[2] In addition, whereas PPAP and selegiline are selective as MAEs of norepinephrine and dopamine, BPAP is a MAE of not only norepinephrine and dopamine but also of serotonin.[1][10][2][4]
PPAP (MK-306) and its (–)-enantiomer (–)-PPAP must not be confused with the sigma receptorligandR(−)-N-(3-phenyl-n-propyl)-1-phenyl-2-aminopropane ((–)-PPAP—same abbreviation)[19] or with the cephamycinantibioticcefoxitin (MK-306—same developmental code name).[20][21][22]
^ abcdefghijklKnoll J (August 2003). "Enhancer regulation/endogenous and synthetic enhancer compounds: a neurochemical concept of the innate and acquired drives". Neurochem Res. 28 (8): 1275–1297. doi:10.1023/a:1024224311289. PMID12834268. Because (–)-deprenyl is a highly potent and selective inhibitor of MAO-B, we performed a structure–activity relationship study to develop a deprenyl-derived enhancer substance free of the MAO-B inhibitory property (11). (–)-1-Phenyl-2-propylaminopentane [(–)-PPAP] is our reference substance with this pharmacological profile. [...] Remarkably, 1 mg/kg (–)-PPAP, a (–)-deprenyl–derived enhancer substance devoid of the MAO-B inhibitory potency of its parent compound, fully antagonized tetrabenazine-induced learning depression in HP rats and was ineffective in LP rats. [...] Furthermore, 3-F-BPAP did not influence the enhancer effect of (–)-PPAP, a (–)-deprenyl analogue free of MAO-B inhibitory potency (34, Fig. 4). The data clearly show that the molecular mechanism through which the PEA-derived substances, (–)-deprenyl and (–)-PPAP, exert their enhancer effect in vivo, is not identical with the one through the stimulation of which the tryptamine-derived substance, (–)-BPAP, acts.
^ abcdefghijklmGaszner P, Miklya I (January 2006). "Major depression and the synthetic enhancer substances, (-)-deprenyl and R-(-)-1-(benzofuran-2-yl)-2-propylaminopentane". Progress in Neuro-Psychopharmacology & Biological Psychiatry. 30 (1): 5–14. doi:10.1016/j.pnpbp.2005.06.004. PMID16023777. S2CID26570703. This was shown with the development of (–)-1-phenyl-2-propylaminopentane, (–)-PPAP, a derivative of (–)-deprenyl which shared the enhancer activity with its parent compound but was free of its MAO-B inhibitory property (Knoll et al., 1992). (–)-PPAP enhanced dopaminergic activity in the brain like (–)-deprenyl. Knoll's progress in clarifying the mechanism of action of (–)-deprenyl responsible for enhanced dopaminergic activity can be followed in his sequent reviews (Knoll, 1978, 1983, 1987, 1992, 1995), until he came to the final conclusion that (–)-deprenyl acts primarily as a PEA-derived synthetic enhancer substance (Knoll, 1998). [...] Since (–)-deprenyl is a highly potent and selective inhibitor of MAO-B, a structure –activity relationship study was performed to develop a deprenyl-derived enhancer substance being free of the MAO-B inhibitory property (Knoll et al., 1992), and (–)-PPAP is at present the reference substance with this pharmacological profile. [...] The subcutaneous administration of 1 mg/kg tetrabenazine, once daily for 5 days, which depletes the catecholamine stores in the brain, significantly inhibits in rats the acquisition of a two-way conditioned avoidance reflex in the shuttle box. Enhancer substances antagonize, in a dose-dependent manner, the inhibition of learning caused by tetrabenazine. The tryptamine-derived selective and highly potent enhancer, BPAP acted in dose range from 0.05 to 10 mg/kg. The PEA-derived enhancer substances, (–)-deprenyl and (–)-PPAP were much less active (1–5 mg/kg).
^ abcdefghijklmnopqKnoll J, Knoll B, Török Z, Timár J, Yasar S (1992). "The pharmacology of 1-phenyl-2-propylamino-pentane (PPAP), a deprenyl-derived new spectrum psychostimulant". Archives Internationales de Pharmacodynamie et de Therapie. 316: 5–29. PMID1356324.
^ abcdefKnoll J, Miklya I, Knoll B, Markó R, Kelemen K (February 1996). "(-)Deprenyl and (-)1-phenyl-2-propylaminopentane, [(-)PPAP], act primarily as potent stimulants of action potential-transmitter release coupling in the catecholaminergic neurons". Life Sciences. 58 (10): 817–827. doi:10.1016/0024-3205(96)00014-8. PMID8602114.
^ abcHealy D (2000). "The Psychopharmacology of Life and Death. Interview with Joseph Knoll.". The Psychopharmacologists, Vol. III: Interviews. London: Arnold. pp. 81–110. doi:10.4324/9781003058892-3. ISBN978-0-340-76110-6. This led us in 1992 to 1-Phenyl-2-propylamino-pentane (PPAP) a completely new and very important compound (Fig. 3.1). We started this work in early 1989. I realized finally that we owe the loss of the catecholamine-releasing property, so characteristic of deprenyl, to the bulky substitution attached to the nitrogen, so we put in bulky substitutions to amphetamine. [...]
^ abcdeMiklya I (November 2016). "The significance of selegiline/(-)-deprenyl after 50 years in research and therapy (1965-2015)". Mol Psychiatry. 21 (11): 1499–1503. doi:10.1038/mp.2016.127. PMID27480491. The demonstration that the DEP analog ( − )-1-phenyl-2- propylaminopentane devoid of MAO inhibitory property, enhanced like DEP the activity of the catecholaminergic brain engine revealed that this effect is unrelated to the selective inhibition of MAO-B. [...] DEVELOPMENT OF (− )-1-PHENYL-2-PROPYLAMINOPENTANE Knoll developed ( − )-1-phenyl-2-propylaminopentane, a DEP analog, which is as equally active with DEP in enhancing the activity of the catecholaminergic brain engine, but it is devoid of MAOI property. This study furnished primary evidence that the main effect of DEP, the specific stimulation of the catecholaminergic brain engine, is unrelated to MAO inhibition.31
^ abcShimazu S, Miklya I (May 2004). "Pharmacological studies with endogenous enhancer substances: beta-phenylethylamine, tryptamine, and their synthetic derivatives". Prog Neuropsychopharmacol Biol Psychiatry. 28 (3): 421–427. doi:10.1016/j.pnpbp.2003.11.016. PMID15093948.
^ abcBandala C, Cárdenas-Rodríguez N, Mendoza-Torreblanca JG, Contreras-García IJ, Martínez-López V, Cruz-Hernández TR, et al. (February 2023). "Therapeutic Potential of Dopamine and Related Drugs as Anti-Inflammatories and Antioxidants in Neuronal and Non-Neuronal Pathologies". Pharmaceutics. 15 (2): 693. doi:10.3390/pharmaceutics15020693. PMC9966027. PMID36840015. DA-releasing agents are a type of drug that induces, through various mechanisms, the release of DA from the presynaptic neuron into the synaptic cleft, leading to an increase in extracellular concentrations of the neurotransmitter. Examples are amphetamine, lisdexamfetamine (L-lysine-d-amphetamine; vyvanse), methamphetamine, methylenedioxymethamphetamine (MDMA), and 4-methylaminorex [27,84–87]. Moreover, (-)1-(benzofuran-2- yl)-2-propylaminopentane, (-)BPAP, (-)-1-phenyl-2-propylaminopentane, and (-)PPAP are enhancers of dopamine activity. BPAP and PPAP act as potent stimulants of neurotransmitter release in dopaminergic neurons, leaving MAO activity largely unchanged. BPAP and PPAP controllably increase the quantity of neurotransmitters that are released when a neuron is stimulated by a neighboring neuron, and they are currently in the research phase [39,88,89].
^ abcGyarmati S, Timár J, Barna L, Knoll B, Knoll J (September 1994). "Reversal of shuttle-box deficit by 1-phenyl-2-propylaminopentane (PPAP)". European Neuropsychopharmacology. 4 (3): 298–299. doi:10.1016/0924-977X(94)90109-0.
^Csaba G, Kovács P, Pállinger E (January–February 2006). "Acute and delayed effect of (-) deprenyl and (-) 1-phenyl-2-propylaminopentane (PPAP) on the serotonin content of peritoneal cells (white blood cells and mast cells)". Cell Biochemistry and Function. 24 (1): 49–53. doi:10.1002/cbf.1183. PMID15584092. S2CID11027835.
^ abSimon K, Harmat V, Török Z, Böcskei Z, Hermecz I (15 August 1996). "1-Phenyl-2-(propylamino)pentane, a Memory Enhancer". Acta Crystallographica Section C Crystal Structure Communications. 52 (8): 2090–2092. Bibcode:1996AcCrC..52.2090S. doi:10.1107/S0108270196005148.
^ abYoneda F, Moto T, Sakae M, Ohde H, Knoll B, Miklya I, et al. (May 2001). "Structure-activity studies leading to (-)1-(benzofuran-2-yl)-2-propylaminopentane, ((-)BPAP), a highly potent, selective enhancer of the impulse propagation mediated release of catecholamines and serotonin in the brain". Bioorg Med Chem. 9 (5): 1197–1212. doi:10.1016/s0968-0896(01)00002-5. PMID11377178.
^Glennon RA, Battaglia G, Smith JD (November 1990). "(-)PPAP: a new and selective ligand for sigma binding sites". Pharmacol Biochem Behav. 37 (3): 557–559. doi:10.1016/0091-3057(90)90027-f. PMID1965044.
^"Cefoxitin". PubChem. U.S. National Library of Medicine. Retrieved 12 August 2024.
^Brogden RN, Heel RC, Speight TM, Avery GS (January 1979). "Cefoxitin: a review of its antibacterial activity, pharmacological properties and therapeutic use". Drugs. 17 (1): 1–37. doi:10.2165/00003495-197917010-00001. PMID369806.
^Yasar S, Timár J, Knoll B, Knoll J (1990). "Comparison of the dependence capacity of amphetamine, MK-306 and (-)deprenyl". Acta Physiol Hung. 75 (Suppl): 299–300. PMID2115235.
^Knoll B, Yasar S, Faragó I, Kovács I, Knoll J (1990). "1-phenyl-2-propyl-aminopentane. HCl (MK-306): A deprenyl-derived new spectrum psychostimulant". European Journal of Pharmacology. 183 (4): 1464–1465. doi:10.1016/0014-2999(90)94608-Z.
^Knoll B, Yasar S, Farago I, Kovacs I, Knoll J (1990). "1-phenyl-2-propyl-aminopentane.HCl (MK-306): a deprenyl-derived new spectrum psychostimulant". European Journal of Pharmacology. 183 (2): 454–455. doi:10.1016/0014-2999(90)93343-O.
^Timár J, Yasar S, Knoll B, Knoll J (1990). "Comparison of the effects of (-)deprenyl, 1-phenyl-2-propyl-aminopentane (MK-306) and amphetamine on the striatal and limbic dopaminergic system". Acta Physiol Hung. 75 (Suppl): 279–280. PMID2115233.
^Knoll B, Timár J, Knoll J (1992). "Analysis of the mechanism of the action of the psychostimulant effect of 1-phenyl-2-propylaminopentane (PPAP). A comparison with amphetamine". Pharmacological Research. 25: 48–49. doi:10.1016/1043-6618(92)90280-O.
^US 5220068, Knoll J, Simay A, Szinnyei E, Somfai E, Torok Z, Mozsolits K, Bergmann J, "Psychostimulant agent", issued 15 June 1993, assigned to Chinoin Private Co Ltd.
^US 5075338, Knoll J, Simay A, Szinnyei E, Somfai E, Torok Z, Mozsolits K, Bergmann J, "Method of treatment of learning deficiency", issued 24 December 2001, assigned to Chinoin Private Co Ltd.
^US 6214859, Yoneda F, Knoll J, Ode H, Sakae M, Katurada M, Moto T, Ando T, Shimazu S, Takahata K, Fujimoto M, "Ethylamine derivatives", issued 10 April 2001, assigned to Fujimoto Brothers Co Ltd.
† References for all endogenous human TAAR1 ligands are provided at List of trace amines
‡ References for synthetic TAAR1 agonists can be found at TAAR1 or in the associated compound articles. For TAAR2 and TAAR5 agonists and inverse agonists, see TAAR for references.