In previous electrophysiological experiments performed by the Principal Investigator on the Pacinian corpuscle, a mammalian mechanoreceptor, graded receptor potentials were measured in response to sinusoidal-displacement stimuli. Those results suggested that there are two populations of transducing elements with each corpuscle, each group having its own directional specificity. Using neurophysiological and anatomical techniques, we plan to link the response properties of these elements to their physical structure. Evidence indicates that these elements are the cytoplasmic extensions of filopodia which emanate from the receptor's axon these elements resembling neuronal growth cones. The filopodia presumably contain actin microfilaments and have been described in many other mechanoreceptors, implying perhaps a similar mechanism for mechanotransduction across receptor types. Using neurophysiological and anatomical (light and electron microscopy) techniques, we plan to test the hypothesis by performing several experiments, specifically designed for that purpose. These include: a) assessing the effects of stimulus probe dimensions into and around the corpuscle; b) measuring the effects of stimulus attack angle by rotating the stimulus probe around the receptor's surface, and c) using tritiated and/or fluorescent neurotoxins specific to the transduction process to help identify the sites of transduction. The significance of the research, in addition to describing possible general mechanisms for transduction, lies in the fact that the Pacinian corpuscle is ubiquitous in the human integument and has been shown to mediate a substantial proportion of the human somatosensory experience. Determining the manner in which Pacinian corpuscles transduce mechanical deformations into neural signals may add significantly to the understanding of the mechanisms involved in the experience of touch.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
1R01NS023933-01A1
Application #
3408018
Study Section
Neurology B Subcommittee 1 (NEUB)
Project Start
1987-04-01
Project End
1990-03-31
Budget Start
1987-04-01
Budget End
1988-03-31
Support Year
1
Fiscal Year
1987
Total Cost
Indirect Cost
Name
University of Rochester
Department
Type
School of Medicine & Dentistry
DUNS #
208469486
City
Rochester
State
NY
Country
United States
Zip Code
14627
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Bell, J; Bolanowski, S; Holmes, M H (1994) The structure and function of Pacinian corpuscles: a review. Prog Neurobiol 42:79-128
Checkosky, C M; Bolanowski, S J (1994) The effect of stimulus duration on frequency-response functions in the Pacinian (P) channel. Somatosens Mot Res 11:47-56
Pietras, B W; Bolanowski, S J (1994) Low cost Video Scaler and Gray Scale Integrator. IEEE Trans Biomed Eng 41:698-703
Bolanowski, S J; Schyuler, J E; Slepecky, N B (1994) Semi-serial electron-micrographic reconstruction of putative transducer sites in Pacinian corpuscles. Somatosens Mot Res 11:205-18
Checkosky, C M; Bolanowski, S J (1992) Effects of stimulus duration on the response properties of Pacinian corpuscles: implications for the neural code. J Acoust Soc Am 91:3372-80
Bolanowski Jr, S J; Gescheider, G A; Verrillo, R T et al. (1988) Four channels mediate the mechanical aspects of touch. J Acoust Soc Am 84:1680-94