Section Days abstract book 2010.indd - RUB Research School ...

LS_14
Investigation on the mechanisms of chemoperception in
human skin
Anna Christina Sondersorg 1 ; Daniela Busse 1 ; Markus Rothermel 2 ; Hanns Hatt 1 &
Heike Benecke 1
1 Department of Cellphysiology; Ruhr-Universität Bochum, 44780 Bochum, Germany
2 Department of Physiology; University of Utah, School of medicine, Salt Lake City, USA
e-mail: Anna-Christina.Sondersorg@ruhr-uni-bochum.de
The trigeminal nerve constitutes the fifth cranial nerve and provides tactile, proprioceptive
and nociceptive afferences that innervate the facial skin, eyes, mouth and the nasal mucosa.
Previous work including studies on anosmic patients indicates a functional contribution of the
trigeminal nerve to odor detection in vivo. High concentrations of most odors typically
provoke trigeminal sensations in vivo, but only certain odors elicit responses in mouse
trigeminal monocultures. This leads to the suggestion that trigeminal perception may require a
transfer of sensory information via crosstalk with additional cell types of the peripheral
innervation area. The expression of several chemoreceptors such as olfactory receptor
proteins and TRP channels as well as their ability to respond to various odors favors the idea
that keratinocytes may participate in odor detection and subsequently transmit signals to
neighboring trigeminal fibers in the epidermis.
This study is designed to a) identify odorants and other chemical substances that activate
keratinocytes but fail to stimulate trigeminal neurons alone, b) to detect potential
communications between skin keratinocytes and trigeminal neurons induced by these
substances and c) to identify possible transmitter molecules.
Using the calcium imaging technique we screened substances with focus on odorants that
reproducibly elicit calcium responses in keratinocytes, but not in trigeminal neurons.
Sandalore and Sandranol, two derivates of sandalwood oil, as well as Histamine turned out to
be good candidates. In contrast to monocultures we could detect increased numbers of
calcium signals in trigeminal neurons in a co-culture approach induced by Sandalore and
Histamine. These results support our hypothesis of an information transfer from keratinocytes
to trigeminal neurons.