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Published on: August 16, 2018
Receptor specificity defines algogenic properties of propofol and fospropofol
Amol Patwardhan1, Rebecca Edelmayer, Emil Annabi
1Department of Anesthesiology, University of Arizona Health Sciences Center, Tucson, AZ 85724, USA.
Background:
Propofol-evoked injection site pain is not observed with fospropofol. We hypothesized that unlike propofol, fospropofol does not activate the irritant receptor, transient receptor potential 1 (TRPA1).
Methods:
We tested the hypothesis using electrophysiology and behavioral studies.
Results:
Our data demonstrate that propofol (100 μM) evokes an inward current only in TRPA1-expressing neurons. However, fospropofol (100 μM and 1 mM) is unable to evoke depolarizing currents in either TRPA1-positive or TRPA1-negative neurons. Both propofol and fospropofol produced general anesthesia.
Conclusions:
The lack of algogenic activity in fospropofol is most likely the result of its inability to activate TRPA1 on nociceptors.
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