D2 Receptor ( Ki = 0.06 nM ); D1 Receptor ( Ki ~350 nM ); D3 Receptor ( Ki = 0.6 nM ); D4 Receptor ( Ki = 0.08 nM ); D5 Receptor ( Ki ~ 3500 nM ); 5-HT2A Receptor ( Ki = 1 nM ); 5-HT1A Receptor ( Ki = 49 nM ); α1B-adrenoceptor; Calcium-activated chloride channel

Spiperone is a strong enhancer of intracellular Ca²⁺ (EC50=9.3 μM) that acts on intracellular Ca²⁺ via a pathway dependent on phospholipase C and coupled to protein tyrosine kinase. This causes increased Cl-secretion in Calu-3 and CFBE41o-cell monolayers[2].
Spiperone reduces nitric oxide production in primary astrocyte, primary microglia, and lipopolysaccharide-stimulated BV-2 microglia cells significantly. Additionally, nitric oxide production in primary microglia cultures stimulated with ATP is markedly inhibited by diperone. Spiperone significantly reduces the BV-2 microglia cells' ability to produce TNF-α. In BV-2 microglia cells, siperone reduces the mRNA expression of proinflammatory cytokines like TNF-α and IL-1β as well as inducible nitric oxide synthase[3].

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Spiperone (1) is a widely used pharmacological tool that acts as a potent dopamine D2, serotonin 5-HT1A, and serotonin 5-HT2A antagonist. Although spiperone also binds at 5-HT2C receptors, it is one of the very few agents that display some (ca. 1000-fold) binding selectivity for 5-HT2A versus 5-HT2C receptors and, hence, might serve as a useful template for the development of novel 5-HT2A antagonists if the impact of its various substituent groups on binding was known. In the present investigation we focused on the 1, 3,8-triazaspiro[4.5]decanone portion of spiperone and found that replacement of the N1-phenyl group with a methyl group only slightly decreased affinity for cloned rat 5-HT2A receptors. However, N1-methyl derivatives displayed significantly reduced affinity for 5-HT1A, 5-HT2C, and dopamine D2 receptors. Several representative examples were shown to behave as 5-HT2 antagonists. As such, N1-alkyl analogues of spiperone may afford entry into a novel series of 5-HT2A-selective antagonists.[7]

Spiperone (1.5 mg/kg; intraperitoneal injection; on days 1, 3, 6, 7, and 13-21; C57Bl/6 mice) treatment inhibits the growth of connective tissue in the parenchyma of Bleomycin lungs and decreases the infiltration of inflammatory cells into the alveolar ducts and alveolar interstitium[6].

Cystic fibrosis (CF) is caused by mutations in the gene producing the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR functions as a Cl(-) channel. Its dysfunction limits Cl(-) secretion and enhances Na+ absorption, leading to viscous mucus in the airway. Ca2+-activated Cl(-) channels (CaCCs) are coexpressed with CFTR in the airway surface epithelia. Increases in cytosolic Ca(2+) activate the epithelial CaCCs, which provides an alternative Cl(-) secretory pathway in CF. We developed a screening assay and screened a library for compounds that could enhance cytoplasmic Ca2+, activate the CaCC, and increase Cl(-) secretion. We found that spiperone, a known antipsychotic drug, is a potent intracellular Ca2+ enhancer and demonstrated that it stimulates intracellular Ca2+, not by acting in its well-known role as an antagonist of serotonin 5-HT2 or dopamine D2 receptors, but through a protein tyrosine kinase-coupled phospholipase C-dependent pathway. Spiperone activates CaCCs, which stimulates Cl(-) secretion in polarized human non-CF and CF airway epithelial cell monolayers in vitro and in CFTR-knockout mice in vivo. In conclusion, we have identified spiperone as a new therapeutic platform for correction of defective Cl(-) secretion in CF via a pathway independent of CFTR. [2]

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The structures of ketanserin (1) and spiperone (2) were examined in detail to determine the role of various substituent groups on 5-HT(2A) receptor affinity and selectivity. It was found that the presence of the quinazoline ring of ketanserin detracts from selectivity and that various ring-opened analogs displayed ketanserin-like affinity and up to 30-fold enhanced selectivity. The triazaspirodecanone portion of spiperone is a major determinant of its 5-HT affinity and selectivity. The conformational rigidity imposed by the ring, as well as the nature of the N(1)-substituent, are important factors in controlling binding at 5-HT(2A), 5-HT(2C), 5-HT(1A), and dopamine D2 receptors. Replacement of the N(1)-phenyl ring of spiperone with a methyl group (KML-010; 48) resulted in a compound that binds at 5-HT(2A) receptors with slightly lower affinity than spiperone, but that lacked affinity (Ki >10,000 nM) for 5-HT(2C) and 5-HT(1A) receptors and binds with 400-fold reduced affinity at D2 receptors. [4]

Glial activation and neuroinflammatory processes play an important role in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and HIV dementia. Activated glia cells can secrete various proinflammatory cytokines and neurotoxic mediators, which may influence neuronal cell survival. Recent studies have demonstrated that glia cell-mediated neuroinflammation is also related to the pathophysiology of schizophrenia. In the present study, anti-inflammatory and neuroprotective effects of antipsychotics were investigated using cultured brain cells as a model. The results showed that spiperone significantly decreased the production of nitric oxide in lipopolysaccharide-stimulated BV-2 microglia cells, primary microglia and primary astrocyte cultures. Spiperone also significantly inhibited nitric oxide production in adenosine 5'-triphosphate (ATP)-stimulated primary microglia cultures. Spiperone markedly decreased the production of tumor necrosis factor-alpha in BV-2 microglia cells. Spiperone attenuated the expression of inducible nitric oxide synthase and proinflammatory cytokines such as interleukin-1beta and tumor necrosis factor-alpha at mRNA levels in BV-2 microglia cells. Spiperone inhibited nuclear translocation and DNA binding of the p65 subunit of nuclear factor kappa B (NF-kappaB), inhibitor of kappa B (IkappaB) degradation, and phosphorylation of p38 mitogen-activated protein kinase in the lipopolysaccharide-stimulated BV-2 microglia cells. Moreover, spiperone was neuroprotective, as the drug reduced microglia-mediated neuroblastoma cell death in the microglia/neuron co-culture. These results imply that the antipsychotic spiperone has anti-inflammatory and neuroprotective effects in the central nervous system by modulating glial activation. [3]

C57Bl/6 mice (7-8-week-old) induced pulmonary fibrosis by Bleomycin
1.5 mg/kg
Intraperitoneal injection; on days 1, 3, 6, 7, and 13-21

rat LD50 oral >1 gm/kg Drugs in Japan, 6(380), 1982
rat LD50 intraperitoneal >500 mg/kg Oyo Yakuri. Pharmacometrics., 3(390), 1969
rat LD50 subcutaneous >50 mg/kg Oyo Yakuri. Pharmacometrics., 3(390), 1969
rat LD50 intravenous 14 mg/kg Psychotropic Drugs and Related Compounds, 2nd ed., Usdin, E., and D.H. Efron, Washington, DC, 1972, -(193), 1972
rat LD50 intramuscular 168 mg/kg Drugs in Japan, 6(380), 1982

[1]. Dopamine receptor pharmacology. Trends Pharmacol Sci. 1994 Jul;15(7):264-70.

[2]. Spiperone, identified through compound screening, activates calcium-dependent chloride secretion in the airway. Am J Physiol Cell Physiol. 2009 Jan;296(1):C131-41.

[3]. The antipsychotic spiperone attenuates inflammatory response in cultured microglia via the reduction of proinflammatory cytokine expression and nitric oxide production. J Neurochem. 2008 Dec;107(5):1225-35.

[4]. Ketanserin and spiperone as templates for novel serotonin 5-HT(2A) antagonists. Curr Top Med Chem. 2002 Jun;2(6):539-58.

[5]. Human umbilical vein vasoconstriction induced by epinephrine acting on alpha1B-adrenoceptor subtype. Am J Obstet Gynecol. 2003 Nov;189(5):1472-80.

[6]. Effect of spiperone on mesenchymal multipotent stromal and hemopoietic stem cells under conditions of pulmonary fibrosis. Bull Exp Biol Med. 2014 May;157(1):132-7.

[7]. Spiperone: influence of spiro ring substituents on 5-HT2A serotonin receptor binding. J Med Chem. 1998;41(25):5084-5093.

Spiperone is an azaspiro compound that is 1,3,8-triazaspiro[4.5]decane which is substituted at positions 1, 4, and 8 by phenyl, oxo, and 4-(p-fluorophenyl)-4-oxobutyl groups, respectively. It has a role as a dopaminergic antagonist, a serotonergic antagonist, an alpha-adrenergic antagonist, an antipsychotic agent and a psychotropic drug. It is an organofluorine compound, an azaspiro compound, a member of piperidines, a tertiary amino compound and an aromatic ketone.
Spiperone is a dopamine antagonist that binds dopamine and serotonin receptors.
A spiro butyrophenone analog similar to HALOPERIDOL and other related compounds. It has been recommended in the treatment of SCHIZOPHRENIA.

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Objective: Our purpose was to determine the presence of alpha(1)-adrenoceptor messenger RNA subtypes and extend the pharmacologic characterization of alpha(1)-adrenoceptors involved in human umbilical vein (HUV) contraction. Study design: Cords (n=124) from healthy patients after term vaginal or cesarean deliveries were used. The vein was carefully dissected out of cords and used for reverse transcription combined with polymerase chain reaction (RT-PCR) to amplify alpha(1)-adrenoceptor transcripts. In isolated organ baths, HUV rings were mounted and cumulative concentration-response curves were constructed either for epinephrine or the selective alpha(1A)-adrenoceptor agonist, A-61603. In other series of experiments, the effects of the selective alpha(1A)- and alpha(1B)-adrenoceptor antagonists (RS-100329 or B8805-033 or spiperone, AH11110A and cyclazosin, respectively) were evaluated to estimate its blocking potencies on epinephrine concentration-response curves. Results: By means of RT-PCR technique alpha(1a)- and alpha(1b)-adrenoceptor transcripts were detected in the HUV. The blocking potency values of RS-100329 or B8805-033 against responses mediated by epinephrine were not consistent with the activation of an alpha(1A)-adrenoceptor population. Moreover, the low potency of the agonist A-61603 was not in accordance with an alpha(1A)-adrenoceptor interaction. On the other hand, the antagonist potencies of spiperone, AH11110A and cyclazosin were in agreement with an interaction on alpha(1B)-adrenoceptor subtype. Conclusion: Although alpha(1a)- and alpha(1b)-adrenoceptor messenger RNAs are detected in the HUV, only alpha(1B)-adrenoceptors are involved in epinephrine vasoconstrictor action. [5]

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The antifibrotic properties of spiperone and its effect on stem and progenitor cells were studied on the model of reversible bleomycin-induced pulmonary fibrosis in C57Bl/6 mice. Spiperone reduced infiltration of the alveolar interstitium and alveolar ducts with inflammatory cells and prevented the growth of the connective tissue in the parenchyma of bleomycin lungs. Apart from anti-inflammatory effect, spiperone suppressed bone marrow hemopoietic cells (CD3, CD45R (B220), Ly6C, Ly6G (Gr1), CD11b (Mac1), TER-119)-, Sca-1+, c-Kit+, CD34- and progenitor hemopoietic cells (granulocyte-erythroid-macrophage-megakaryocytic and granulocyte CFU). Spiperone-induced disturbances of fi brogenesis were paralleled by restoration of endothelial cells in the lung parenchyma, reduction of the number of circulating bone marrow cells and lung mesenchymopoietic cells (mesenchymal multipotent stromal cells (CD31-, CD34-, CD45-, CD44+, CD73+, CD90+, CD106+) and progenitor fi broblast cells), and suppression of multilineage differentiation of multipotent mesenchymal stromal cells (including fi broblast-lineage cells). [6]

C23H26FN3O2

395.47

395.201

C, 69.85; H, 6.63; F, 4.80; N, 10.63; O, 8.09

749-02-0

Spiperone hydrochloride; 2022-29-9

5265

Off-white to light yellow solid powder

630.6ºC at 760 mmHg

190-193.6ºC

335.2ºC

3.548

1

5

6

29

577

0

O=C(C1=CC=C(F)C=C1)CCCN2CCC3(CC2)N(CNC3=O)C4=CC=CC=C4

DKGZKTPJOSAWFA-UHFFFAOYSA-N

InChI=1S/C23H26FN3O2/c24-19-10-8-18(9-11-19)21(28)7-4-14-26-15-12-23(13-16-26)22(29)25-17-27(23)20-5-2-1-3-6-20/h1-3,5-6,8-11H,4,7,12-17H2,(H,25,29)

8-[4-(4-fluorophenyl)-4-oxobutyl]-1-phenyl-1,3,8-triazaspiro[4.5]decan-4-one

E 525; R-5147; spiperone; 749-02-0; Spiropitan; Spiroperidol; Espiperona; Spiperonum; R 5147; [3H]spiperone; NSC-170983; Spiperone; E525; R 5147; NSC170983; E-525; R5147; NSC 170983

2934.99.03.00

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO: ~33.3 mg/mL (~84.3 mM)

Solubility in Formulation 1: ≥ 4.55 mg/mL (11.51 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 45.5 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (6.32 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)