Table 1.

Summary of cellular and molecular effects of menthol.

Target protein or cellular event	End-point measured	Effect	Concentration and ligand	Preparation	References
Na+ channels	Ion current	Inhibition	IC50 = 376 μM (In neuronal Na+ channels)	HEK293 cells	Haeseler et al., 2002
			IC50 = 571 μM (In skeletal muscle Na+ channels)
Na+ channels	Ion current	Inhibition	IC50 = 297 μM	Cultured dorsal horn neurons	Pan et al., 2012
TTX-resistant Na+ channels	Ion current	Inhibition	IC50 = 299–500 μM	DRG neurons and immortalized DRG neuron-derived F11 cells	Gaudioso et al., 2012
Nav1.8 channel subtype			>300 μM
			540–807 μM
Nav1.9 channel subtype
TTX-sensitive Na+ channels
Na+ channels	Compound action potential	Inhibition	IC50 = 1.1 mM (−)-menthol	Frog sciatic nerve fibers	Kawasaki et al., 2013
			IC50 = 0.9 mM (+)-Menthol
Na+ channels	Number and duration of action potential bursts	Inhibition	250 μM	Mouse cortical neurons	Pezzoli et al., 2014
DHP-sensitive and DHP-insensitive Ca2+ channels	Ion current	Inhibition	IC50 = 0.25 mM	LA-N-5 cells	Sidell et al., 1990
Ca2+ channels	High K+-induced intracellular Ca2+ increase	Inhibition	2 mM	Leech neurons	Dierkes et al., 1997
Ca2+ channels	Ca2+ uptake and contractile response	Inhibition	IC50 = 8–28 μg/ml	Ilium	Hawthorn et al., 1988
			IC50 = 10–69 μg/ml	Cardiac tissue synaptosomes and chick retinal neurons
Ca2+ channels	KCl-preconstricted smooth muscle contraction	Inhibition	IC50 = 58 μM	Bronchial smooth muscle fibers	Wright et al., 1997
			IC50 = 120 μM
	ACh-preconstricted smooth muscle contraction
Ca2+ channels	Intracellular Ca2+	Inhibition	0.01–1 mM	Tracheal smooth muscle fibers	Ito et al., 2008; Wang et al., 2016
Ca2+ channels	Intracellular Ca2+	Inhibition	300 μM	Detrusor muscle	Ramos-Filho et al., 2014
Ca2+ channels	Intracellular Ca2+	Inhibition	0.1–1 mM	Vas deference	Filippov et al., 2009; Vladymyrova et al., 2011
Ca2+ channels	Ca2+ influx and smooth muscle relaxation	Inhibition	0.1–1 mM	Rat aorta, mesenteric and coronary arteries	Cheang et al., 2013
Ca2+ channels	Ca2+ influx and contraction	Inhibition	0.1–30 mM	Gastrointestinal smooth muscle and human colon circular muscle	Amato et al., 2014a
Ca2+ channels	High K+ and Ca2+ evoked contractions	Inhibition	IC50 = 22.1 μg/mL	Guinea pig taenia coli	Hills and Aaronson, 1991
			IC50 = 25.9 μg /mL	Guinea pig colon
			IC50 = 15.2 μg /mL	Rabbit jejunum
Ca2+ channel	Ca2+ current	Inhibition	0.1–0.5 mM	Helix neurons	Swandulla et al., 1986
Low voltage-activated Ca2+ channel (T-type like) and high voltage activated Ca2+ channel (L-type like)	Ca2+ current	Inhibition	0.1–1 mM	Cultured DRG neurons	Swandulla et al., 1987
L-type VGCCs	Ca2+ current	Inhibition	IC50 = 74.6	Rabbit ventricular myocyte	Baylie et al., 2010
TRPM8	Ca2+ current	Activation	300 μM	Rat tail artery myocytes	Melanaphy et al., 2016
L-type VGCCs		Inhibition
IP3 receptors		Activation
Ryanodine receptors	Ca2+ efflux	Activation	EC50 =1 mM	Isolated sarcoplasmic reticulum	Palade, 1987; Mahieu et al., 2007; Neumann and Copello, 2011
				HEK239 cells
Ca2+-activated K+ channels	Ion current	Activation	100 μM	Human glioblastoma cells	Wondergem and Bartley, 2009
Kv7.2/3 channel	Ion current	Suppression	IC50 = 289 μM	Cultured sensory neurons	Vetter et al., 2013
TRPM8 channels	Intracellular Ca2+	Activation	10 μM and 100 μM	CHO cells	McKemy et al., 2002; Peier et al., 2002
			EC50 = 66.7 μM	Xenopus laevis oocytes
TRPM8 channels	Menthol sensitivity of TRPM8 channel	Altered	10, 100, and 1000 μM	Mutant voltage sensor residues (TM4 and TM4-TM5 linker) of human TRPM8 channel expressed in HEK 293 cells	Voets et al., 2007
TRPM8 channels	Menthol sensitivity to TRPM8 channel	Reduction	300 μM	Mutant tyrosine 745 residue in TM2 of mouse TRPM8	Bandell et al., 2006
TRPM8 channels	Ion current	Activation	EC50 = 4–80 μM	Trigeminal ganglia neuronal cells	McKemy et al., 2002; Peier et al., 2002; Behrendt et al., 2004
				CHO Cells
				HEK293 calls
TRPV3 channels	Ion current	Activation	0.5–2 mM	CHO cells	Macpherson et al., 2006; Vogt-Eisele et al., 2007
			1 mM	HEK293 cells
				Primary keratinocyte culture
TRPA1 channels	Ion current	Activation (at low concentration)	1–30 μM	CHO cells	Macpherson et al., 2006; Karashima et al., 2007; Kim et al., 2016
			1–10 μM	Interstitial cells of Cajal
				CHO cells
		Inhibition (at high concentration)	0.25–1 mM
TRP-independent effects	Intracellular Ca2+	Inhibition	EC50 = 0.9–1 mM	Skeletal muscle sarcoplasmic reticulum	Palade, 1987; Takeuchi et al., 1994; Tsuzuki et al., 2004; Lu et al., 2006; Mahieu et al., 2007; Wondergem and Bartley, 2009; Neumann and Copello, 2011
			100 μM–1 mM	Tracheal epithelial cells
			25–100 μM	Human leukemia cells
			100 μM	Gliablastoma cells
			100 μM–1 mM	Cell lines and dorsal horn neurons
PCL enzyme activity	P2Y purinoreceptor-mediated/histamine receptor-mediated cytosolic Ca2+ mobilization	Inhibition	0.3–1 mM	HEK-293 cells	Kim et al., 2008
				HeLa cells
Anion transport	CFTR-mediated Cl− transport	Potentiation	0.1–1 mM	Human airway Calu-3 epithelial cells	Morise et al., 2010
	Na+-K+-2Cl− transporter	Down regulation
GABAA (α1β2γ2s) receptors	Ion current	Potentiation	EC50 = 25 μM	Xenopus laevis oocytes	Hall et al., 2004
Glycine (α1 homomers) receptors			EC50 = 75 μM
GABAA receptors	Righting reflex	Inhibition	EC50 = 23 μM	In vivo tadpole assay	Watt et al., 2008
GABAA receptors	[3H]-flunitrazepam binding	No effect	Up to 500 μM	Cultured mouse cortical neurons	García et al., 2006; Corvalán et al., 2009
		Stimulation	EC50 = 1.55 μM	Membranes from chick forebrain
GABAA receptors	[3H]-TBOB binding	Inhibition	LD50= 128.9 μg fly−1	Housefly head membrane preparations	Tong and Coats, 2012
GABAA receptors	Ion current	Activation	100 μM	Cultured rat hippocampal neurons	Zhang et al., 2008
GABAA receptors	Ion current	Activation	0.1–1 mM	brainstem-spinal cord of newborn rats	Tani et al., 2010
GABAA receptors	Ion current	Activation	150–750 μM	Periaqueductal gray (PAG) neurons of midbrain slices	Lau et al., 2014
5-HT3 receptors	[14C] guanidinium influx	Inhibition	10 μM–1 mM	N1E-115 cells	Heimes et al., 2011
	Isotonic contractions	Inhibition		Isolated rat ileum
5-HT3A receptors	Ion current	inhibition	IC50 = 163 μM.	Xenopus laevis oocytes	Ashoor et al., 2013a
Human recombinant homomeric 5-HT3A	Ca2+ influx	Inhibition	IC50 = 4.75 mM for (−)-menthol	HEK293 cells	Walstab et al., 2014
Human recombinant heteromeric 5-HT3AB receptors			IC50 = 4.75 mM for (+)-Menthol
			IC50 = 4.46 mM for (−)-menthol
			IC50 = 4.60 mM for (+)-Menthol
Nicotinic receptors	Nicotine-induced irritation and sensory perception	Reduction	0.3% L-menthol	Tongue (human subject)	Dessirier et al., 2001
Nicotinic receptors	Respiratory irritation response	Reduction	16 ppm	Female C57BL/6J mice	Willis et al., 2011
Nicotinic receptors	nicotine-induced hypothermia	Inhibition	100-400 mg/Kg	Male adult rats	Ruskin et al., 2008
Nicotinic receptors	Gastric relaxation	Induction	0.3-30 mM	Male adult mice	Amato et al., 2014b
Nicotinic receptors (α4β2 nAChRs)	Ion current	Inhibition	IC50 = 111 μM.	Trigeminal neurons in HEK tsA201 cells	Hans et al., 2012
Nicotinic receptors (α4β2 nAChRs)	Density of α4β2 nAChR in menthol smokers	Up-regulation	Menthol cigarette smokers vs nonsmokers	Human subjects	Brody et al., 2013
Nicotinic receptors subunits	α4 and α6 nAChR subunits	Up-regulation	2 mg/kg/h for in vivo upregulation assays	Midbrain dopaminergic neurons from mice	Henderson et al., 2016
	(α4)3(β2)2 nAChR subunits	Up-regulation	500 nM	Neublastoma cells
	Decay phase of current	Acceleration	2 mg/kg/10d	Mouse brain slices
Nicotinic receptors (α7 nAChRs)	Ion current	Inhibition	IC50 = 32.6 μM	Xenopus laevis oocytes	Ashoor et al., 2013b
Nicotinic receptors (α3β4 nAChRs)	Ion current	Desensitization	Up to 1 mM	HEK 293 cells and mouse sensory neurons	Ton et al., 2015