Mapping of intranasal mucosal thermal sensitivity
Tue-P1-013
Presented by: Pauline Hanslik
Introduction: The olfactory and trigeminal intranasal systems are closely interlinked. Although olfactory sensitivity receives much attention - especially after the SARS-CoV2 pandemic with many people experiencing olfactory loss - little is known about intranasal trigeminal functions. Hence, this study aimed to characterize the intranasal trigeminal sensitivity to heat in relation to the expression of transient receptor potential channels (TRP).
Methods: A total of 20 healthy participants (aged 21-27 years, 11 women) were screened for olfactory function and trigeminal sensitivity. Under endoscopic control, thresholds to thermal stimuli were determined in 7 locations: anterior septum, lateral vestibulum, interior nose tip, lower turbinate, middle septum, middle turbinate, and olfactory cleft. For analyses of the expression of trigeminal receptors (TRPV1, TRPV3, TRPA1, TRPM8) nasal swabs were obtained at the anterior septum, middle turbinate, and olfactory cleft.
Results: Thermal thresholds differed between locations (p=0.018), with a trend of higher thresholds at the anterior septum (p=0.092). At all sites the highest receptor mRNA expression was detected for TRPV1 (p<0.001). The expression of TRPV3 RNA was highest at the anterior septum compared to the middle turbinate or olfactory cleft. Thermal sensitivity correlated between TDI-score and trigeminal intensity ratings, a questionnaire regarding trigeminal function, nasal patency, and CO2 threshold, but there was no correlation with receptor RNA expression.
Discussion: These results suggested that there are topographical differences between the intranasal thermal threshold with the anterior septum being least sensitive to thermal stimuli.
Funding and acknowledgement: This project has received funding from the European Union's Horizon 2020 under grant agreement No. 964529 (ROSE). We also would like to thank Nicole Power Guerra for help with the statistical analyses.
Methods: A total of 20 healthy participants (aged 21-27 years, 11 women) were screened for olfactory function and trigeminal sensitivity. Under endoscopic control, thresholds to thermal stimuli were determined in 7 locations: anterior septum, lateral vestibulum, interior nose tip, lower turbinate, middle septum, middle turbinate, and olfactory cleft. For analyses of the expression of trigeminal receptors (TRPV1, TRPV3, TRPA1, TRPM8) nasal swabs were obtained at the anterior septum, middle turbinate, and olfactory cleft.
Results: Thermal thresholds differed between locations (p=0.018), with a trend of higher thresholds at the anterior septum (p=0.092). At all sites the highest receptor mRNA expression was detected for TRPV1 (p<0.001). The expression of TRPV3 RNA was highest at the anterior septum compared to the middle turbinate or olfactory cleft. Thermal sensitivity correlated between TDI-score and trigeminal intensity ratings, a questionnaire regarding trigeminal function, nasal patency, and CO2 threshold, but there was no correlation with receptor RNA expression.
Discussion: These results suggested that there are topographical differences between the intranasal thermal threshold with the anterior septum being least sensitive to thermal stimuli.
Funding and acknowledgement: This project has received funding from the European Union's Horizon 2020 under grant agreement No. 964529 (ROSE). We also would like to thank Nicole Power Guerra for help with the statistical analyses.