Effects of Asarone and Β‐asarone on Conditioned Responses, Fighting Behaviour and Convulsions

Abstract

In the Ayurvedic system of medicine, the roots and rhizomes of an indigenous Indian plant Acorus calamus are used together with the roots of Rauwolfia serpentina for treating many mental ailments. The influence of asarone and beta-asarone (the trans and cis forms of 2,4,5-trimethoxy-1-propenyl benzene), two active principles of Acorus calamus, when given alone and together with either reserpine or chlorpromazine, has been studied on the conditioned avoidance response of trained rats, on the fighting behaviour of paired mice subjected to mild foot shock and on electro-convulsions. Except for electro-convulsions, asarone in small doses potentiates the effects of reserpine and of chlorpromazine; beta-asarone has no such effect. Estimation of the 5-hydroxytryptamine content of rat brain showed that neither acorus oil nor its active principles increase the concentration of 5-hydroxytryptamine; nor do these compounds cause an additional decrease in the 5-hydroxytryptamine content of the brains of animals treated with reserpine. It is concluded that the potentiating effect of these principles is unrelated to 5-hydroxytryptamine concentration. In experiments using electro-convulsions, asarone increased the percentage mortality of animals treated with chlorpromazine but not of those treated with reserpine.

Acorus calamus.: Scientific Validation of Ayurvedic Tradition from Natural Resources

“…Bhattacharya, 1968;Bose et al, 1960;Dandiya et al, 1959a,b;Dandiya & Cullumbine, 1959;Dhalla & Bhattacharya, 1968;Malhotra et al, 1962 CNS depressant activities Essential oil, a-asarone, b-asarone, alcohol extract, aqueous extract Dandiya & Menon, 1964Menon & Dandiya. 1967;Sharma et al, 1961;Tripathi & Singh, 1995;Zanoli et al, 1998;Hazra & Guha, 2003 Anticonvulsant activity Essential oil, aqueous extract, alcohol extract, a-asarone Dandiya & Cullumbine, 1959;Dandiya & Menon, 1963;Dandiya & Sharma, 1962;Khare & Sharma, 1982;Madan et al, 1960;Manis et al, 1991;Sharma et al, 1961 Behavorial changes Essential oil, aqueous extract, alcohol extract, a-asarone Chak & Sharma, 1965;Dandiya et al, 1958;Dandiya & Cullumbine, 1959;…”

“…b-Asarone caused generalized convulsion and potentiated metrazol seizures in rats, while a-asarone showed a tendency to protect against metrazol convulsions and modified electroshocks (Sharma et al, 1961). In a study using electroconvulsions, a-asarone increased the percentage mortality of animals treated with chlorpromazine but not of those treated with reserpine (Dandiya & Sharma, 1962;Dandiya & Menon, 1963). The aqueous and alcohol extracts were found to reduce the severity of maximum electric shock-induced seizure in rats.…”

“…Estimation of brain 5-HT content of rat revealed that neither the oil nor its active principles liberated 5-HT. These compounds also did not cause additional decrease of the brain 5-HT content in reserpine-treated animals (Dandiya & Sharma, 1962;Dandiya & Menon, 1963;). The oil also caused hypothermia in mice and, even in low doses, counteracted LSDinduced hyperpyrexia.…”

Positive GABAA Receptor Modulators from Acorus calamus and Structural Analysis of (+)-Dioxosarcoguaiacol by 1D and 2D NMR and Molecular Modeling

“…[52][53][54] There are many reports of sedative and tranquillizing properties of Acorus extracts and essential oil in animal models, but the mechanism of action was not established up to now. [10][11][12][13][14][15]55 Given that β-asarone (1) is a major compound of the essential oil, its sedative and tranquillizing activities may be due to the GABA A receptor modulating properties of 1. The quantity of β-asarone in Acorus rhizome and essential oil, however, depends on the chemotype and thus varies considerably.…”

“…[7][8][9] Several in vivo studies support a sedative and tranquillizing action of the essential oil and of ethanolic and aqueous extracts of A. calamus. [10][11][12] Up to now, the underlying mechanism of action has remained elusive despite various investigations, even though the pharmacological effect could be mainly attributed to α-asarone and β-asarone. 11,[13][14][15] GABA A receptors are pentameric ligand-gated chloride ion channels that are activated by GABA, the major inhibitory neurotransmitter in the CNS.…”