In many vertebrates, intraspecies signals have been shown to alter social and/or endocrine-related behaviors. These chemosensory signals are thought to be detected and processed by specialized receptor cells (bipolar neurons) of the vomeronasal (VN) organ. The function of the VN organ has been thought to be exclusively linked to pheromone stimulation, however, a variety of data has accumulated to suggest that the VN organ also detects general odors. To date, definitive experiments elucidating such actions on individual VN bipolar neurons have not been performed. The overall objective of this grant proposal is to determine the precise mechanism(s) involved in the detection and transduction of pheromone and/or general odor signals in isolated mouse VN bipolar neurons.
Four specific aims are proposed. First is to characterize the electrophysiological, biophysical and pharmacological properties of VN bipolar neurons in the absence of pheromones and general odorants. Whole-cell voltage- and current-clamp recordings will be made at the soma to study the generic membrane properties of VN bipolar receptor neurons. Second is to determine the kinetic properties of pheromone and general odor-induced currents. Here species specific pheromones and general odorants will be applied via a puffer pipette to the dendrite, while recordings from the soma of the same bipolar neuron will be made under whole-cell voltage- and current-clamp mode. Third is to determine the effects of non-genomic and genomic actions of steroids on the kinetics of pheromone- and general odor-induced currents recorded under whole-cell voltage- and current-clamp configuration. Fourth is to determine the role of the cyclic nucleotides in the pheromone- and odor-induced currents in VN bipolar neurons. Pheromones and odors will be applied via puffer pipette while recordings will be made under whole-cell, cell- attached and inside-out patch configuration to dendrites of VN bipolar neurons. The completion of these studies will provide a basic foundation for understanding how pheromone signals are detected and how this information is transduced into electrical events for subsequent transmission to the central nervous system. The results could also provide information relevant to our basic understanding of the cellular events underlying intraspecies communication, emotions and feelings as well as psychiatric/endocrine abnormalities such as bipolar disorder (mood swings) and Kallmann's syndrome.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Research Project (R01)
Project #
5R01DC002120-05
Application #
2856597
Study Section
Sensory Disorders and Language Study Section (CMS)
Project Start
1995-01-01
Project End
2000-12-31
Budget Start
1999-01-01
Budget End
2000-12-31
Support Year
5
Fiscal Year
1999
Total Cost
Indirect Cost
Name
University of Texas Sw Medical Center Dallas
Department
Physiology
Type
Schools of Medicine
DUNS #
City
Dallas
State
TX
Country
United States
Zip Code
75390
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Moss, R L; Flynn, R E; Shi, J et al. (1998) Electrophysiological and biochemical responses of mouse vomeronasal receptor cells to urine-derived compounds: possible mechanism of action. Chem Senses 23:483-9
Moss, R L; Flynn, R E; Shen, X M et al. (1997) Urine-derived compound evokes membrane responses in mouse vomeronasal receptor neurons. J Neurophysiol 77:2856-62
Guo, J; Zhou, A; Moss, R L (1997) Urine and urine-derived compounds induce c-fos mRNA expression in accessory olfactory bulb. Neuroreport 8:1679-83
Zhou, A; Moss, R L (1997) Effect of urine-derived compounds on cAMP accumulation in mouse vomeronasal cells. Neuroreport 8:2173-7
Dudley, C A; Rajendren, G; Moss, R L (1996) Signal processing in the vomeronasal system: modulation of sexual behavior in the female rat. Crit Rev Neurobiol 10:265-90