and pharmacological actions of fragrant substances
oils have been used
for over 5000 years as perfumes and for mental, spiritual and physical
healing. The effects of an aroma can be instanteous and include both
direct and indirect psychological effects – even thinking
smell may have effects similar to the smell itself.
that inhaled or dermally applied essential oils enter the blood stream
and due to their hydrophobic nature are able to cross the
blood-brain-barrier indicates that the beneficial effects of aromatic
substances are primarily pharmacological. This conclusion is supported
by increasing benefits of aromatherapy using specific essential oils in
the management of chronic pain, depression, anxiety and some cognitive
disorders, as well as insomnia and stress-related disorders. The use of
flavours with CNS activity as therapeutics might revolutionise the
psychotherapeutical praxis since there are no known adverse reactions
of flavour known as today.
possible docking point of
fragrant substances within the CNS is the g-amino butyric acid (GABA)
system. Ligands which contribute to GABAA
receptor activation typically have anxiolytic, anticonvulsant,
sedative, and muscle relaxant properties
substances with affinity to the GABAA
receptor comprise thymol, menthol or the fragrant fractions of whisky
or Oolong tea. This binding of essential oil components to GABA
receptors may contribute to the calmative effects of thyme, mint or
and not less interesting docking point of fragrant substances within
the CNS are the voltage-sensitive calcium channels. They are a group of
voltage-gated ion channels found in excitable cells (like muscle cells
or neurons). The most prominent binding site in voltage-sensitive
calcium channels is the so-called alpha2delta (a2d)
subunit. a2d Ligands are an evolving drug class
which bind to one of the auxiliary subunits constituing
voltage-sensitive Ca2+ channels, thereby
influencing Ca2+ transport into the cells. They
have only minimal effects on physiological synaptic function, but they
reduce excessive Ca2+
influx under hyperexicitable or pathological conditions. This
modulation is characterised by a reduction of the excessive
neurotransmitter release that is observed in stress and certain
neurological and psychiatric disorders. In other words, the action of a2d
ligands on the voltage-sensitive calium channels helps to bring a
disturbed neuronal system back to balance.
subunit of voltage sensitive calcium channels may be the molecular site
of action of fragrant substances with known activity in the CNS like
lavender and lemon balm oil and bergamot oil with their mood improving
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