Associate Professor of Swine Production Medicine, Department of Clinical Studies – New Bolton Center, University of Pennsylvania School of Veterinary Medicine

Secondary Appointment - Associate Professor of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania School of Medicine

Research Areas: Swine production, Neurotransmitter release–auditory system, Synaptic mechanisms in auditory system, Swine health
PubMed Link
Contact Information:
University of Pennsylvania
School of Veterinary Medicine
Dept of Clinical Studies
New Bolton Center
382 West Street Road
 Phone 610-925-6554
 Fax 610-925-6834
 Email thd@vet.upenn.edu

Cellular and molecular mechanisms of neurotransmitter release

exocytosis, endocytosis, synaptic transmission, neurotransmitter release

time-resolved detection of neurotransmitter release from single cells: cell membrane capacitance, amperometric voltametry, and voltage clamp of detector cells or sniffer patches; optical monitoring and modulation of intracellular calcium; fluorescent indicator dyes of calcium, and photolabile chelators of calcium; cell culture and brain slice-like preparations.

My laboratory focuses on pre-synaptic mechanisms of neurotransmitter release. Hearing dictates that the inner hair cell of the cochlea must release transmitter for prolonged periods and with exquisite temporal fidelity. Mechanisms of neurotransmitter release are being studied to understand the cellular and molecular specializations utilized by different parts of the nervous system to meet their unique requirements for neurotransmission.

Primary area of research:
Basic sciences – Neuroscience with a special emphasis on synaptic mechanisms in the auditory system.
Clinical science – Swine health and well-being

Parsons, T.D., J.C. Coorssen, H. Horstmann, and W. Almers. Docked granules, the exocytic burst and the need for ATP hydrolysis in endocrine cells. Neuron. 15: 1085-1096, 1995.

Parsons, T.D. and P. Sterling. Synaptic ribbon: a conveyor belt or safety belt? Neuron 37: 379-382, 2003.

*Spassova, M., M. Avissar, A.C. Furman, M.A. Crumling, J.C. Saunders & T.D. Parsons. Evidence that rapid replenishment of the synaptic ribbon with vesicles mediates recovery from short-term adaptation at the hair cell afferent synapse. J.Assc.Res.Otolaryn. 5: 376-390, 2004.

Parsons, T.D. Auditory fidelity. Nature. 444: 1013-1014, 2006.

Hughes, E.G., Peng, X., Gleichman, A.J., Lai, M., Zhou, L., Tsou, R., Parsons, T.D., Lynch, D.R., Dalmau, J., Balice-Gordon, R.J. Cellular and synaptic mechanisms of anti-NMDA receptor encephalitis J Neurosci 28: 5866-75, 2010.

*Wittig, J.H. Jr., Parsons, T.D. Synaptic ribbon enables temporal precision of hair cell afferent synapse by increasing the number of readily releasable vesicles: A modeling study J Neurophysiol 100: 1724-1739, 2008.

Bell, T.J., Miyashiro, K.Y., Sul, J.Y., Jochems, J., Haydon, P.G., Parsons, T.D., Eberwine, J. Cytoplasmic BKCa channel pre-mRNAs contribute to the excitability of hippocampal neurons Proc Natl Acad Sci U S A 12: 1901-6, 2008.

*Avissar, M., Furman, A.C., Saunders, J.C., Parsons, T.D. Adaptation reduces spike count reliability, but not spike timing precision, of auditory nerve responses J Neurosci 13: 6461-72, 2007.

*Hassinger, W.J., K.A. Monahan, K.A. T.L. Scanlon, Parsons, T.D. Nutrient management practices among swine operations of various sizes J. Am.Vet. Med. Assc. 217: 1526-1535, 2000.

Gardner, I.A., T.E. Carpenter, L. Leontidis, Parsons, T.D. Financial evaluation of vaccination and testing alternatives for control of parvovirus-induced reproductive failure in swine J. Am. Vet. Med. 208: 863-869, 1996.

V.M.D. (Veterinary Medicine) University of Pennsylvania, 1986

Ph.D. (Neuroscience) University of Pennsylvania, 1989

B.A. (Biology & Neuroscience, Magna Cum Laude) Amherst College, 1982