Our laboratory studies sensory neurobiology, and specifically the transmission of orosensations (e.g., taste, pain, temperature, irritating chemicals) from peripheral sensory structures into the brain.
Ongoing projects include tests of orofacial pain and taste dysfunction that result from off target side effects of cancer chemotherapy such as oxaliplatin- and cisplatin-induced oral cold allodynia and dysgeusia. The premise is that taste changes and orofacial pain after oxaliplatin or cisplatin chemotherapy may be due, in part, to pathological changes in the sensory ganglia that innervate the tongue, head and neck, the geniculate and trigeminal ganglia. Because these ganglia lie outside the blood-brain barrier, pathological changes there may be treatable by drugs and agents injected into the blood stream, raising hopes for developing effective means to alleviate the painful side effects of chemotherapy.
We also are investigating the molecular physiology of taste, including how taste bud cells respond to salt stimulation and how taste is coded by sensory neurons in the geniculate ganglion.
We use mice that express the calcium-sensitive protein, GCaMP, in sensory afferent neurons. This allows us to image the activity of these sensory neurons in a living, anesthetized animal where the geniculate or trigeminal ganglion has been surgically exposed. The neuronal activity is imaged using a scanning laser confocal microscope equipped with a long-working distance, high-power objective.
Leijon SC, Chaudhari N, Roper SD. (2019) Mouse trigeminal neurons respond to kokumi substances, Chapter 9 in Koku: Food Science and Physiology. (ed. Nishimura T, Kuroda M). Singapore: Springer. In press. Available from: https://www.biorxiv.org/content/10.1101/540237v1
Leijon SCM, Neves AF, Simon SA, Chaudhari N, Roper SD (2019) Oral thermosensing by murine trigeminal neurons: modulation by capsaicin, menthol, and mustard oil. J Physiol Jan 17 [Epub ahead of print]. PMID: 30656684
Ohla K, Yoshida R, Roper SD, Di Lorenzo PM, Victor JD, Boughter Jr. JD, Fletcher M, Katz DB, Chaudhari N. (2018) Recognizing taste: coding patterns along the neural axis in mammals. Chem Senses, In press: bjz013, https://doi.org/10.1093/chemse/bjz013 PMID not yet assigned.
Dvoryanchikov D, Hernandez D, Roebber JK, Hill DL, Roper SD, Chaudhari N (2017) Chemosensory and somatosensory neurons with distinct transcriptomes and functional properties co-exist in the geniculate ganglion. Nature Communic 8:760
Roper, S and Chaudhari, N (2017). Taste buds: cells, signals, and synapses. Nature Reviews Neuroscience 18:485-497
Wu A, Dvoriantchikov G, Pereira E,, Chaudhari N, Roper SD (2015) Breadth of tuning in taste afferent neurons varies with stimulus strength. Nature Communic 6:8171
Dando R, Pereira E, Kurian M, Barro-Soria R, Chaudhari N, Roper S (2015) A Permeability Barrier Surrounds Taste Buds in Lingual Epithelia. Am. J. Physiol-Cell Physiol 308:C21-32
Roper SD. (2015) The taste of table salt. Pflugers Arch 467:457-63
Complete List of Published Work in MyBibliography hosted at NCBI: http://www.ncbi.nlm.nih.gov/sites/myncbi/stephen.roper.1/bibliography/42785362/public/?sort=date&direction=ascending