David L. Kreulen, Ph.D.
Kreulen Lab Web Site
Areas of Research Interest [PDF]
Regulation of the sympathetic nervous system; relationships between sympathetic neuron properties and the regulation of blood vessels; neuromuscular transmission in blood vessels.
In the autonomic nervous system the final neurons that innervate end organs are grouped in autonomic ganglia. Ganglionic neurons are sites of integration of efferent and sensory synaptic signals into a coordinated regulation of multiple end organs whose function is often diverse. My research interests are in the properties of sympathetic ganglia and the relationship of the characteristics of individual neurons to the regulation of the cardiovascular and gastrointestinal systems. To understand how the sympathetic ganglia regulate and coordinate vascular and gastrointestinal function we are asking the following questions:
- What is the anatomical organization of the sympathetic ganglia innervating the gastrointestinal tract and its blood supply?
- Do individual neurons innervate multiple targets or just one type of tissue?
- Do individual neurons innervate both arteries and veins?
- Does a neuron that innervates an artery have properties that differentiate it from a neuron that innervates a vein?
- What are the membrane electrical properties of neurons that might distinguish one functional type from another?
- What transmitters are released from "artery neurons" or "vein neurons"?
- What are the events in neuromuscular transmission in arteries and veins?
- What are the developmental cues that neurotrophic factors from artery or vein provide to determine the functional properties of sympathetic neurons?
1.The organization of neurons in sympathetic ganglia based on innervation target.
2.Electrophysiologic properties of different functional classes of sympathetic neurons.
3.Interactions between primary sensory nerves and sympathetic ganglionic neurons.
4.Trophic interactions between sympathetic ganglia and their target tissues.
5.Comparison of neuromuscular transmission in artery and vein.
Meehan, A.G. and Kreulen, D.L. Capsaicin-sensitive inhibitory reflex from the gut to mesenteric arteries. J. Physiol. (London), 448: 153-159, 1992.
Morris, J.L., Gibbins, I.L., Kadowitz, P.J., Herzog, H., Kreulen, D.L., Toda, N. and Claing, A. Roles of peptides and other substances in cotransmission from vascular autonomic and sensory neurons. Canadian J. Physiology and Pharmacology, 73: 521-532, 1995.
Zheng, Z.L., Shimamura, K., Anthony, T.L., Travagli, R.A., and Kreulen, D.L. Nitric oxide is a sensory nerve neurotransmitter to the mesenteric artery of guinea pig. J. Autonomic Nervous System 67:137-144, 1997.
Browning, K.N., Zheng, Z.L., Kreulen, D.L. and Travagli, R.A. Effects of nitric oxide in cultured prevertebral sympathetic ganglion neurons.J. Pharm. Exp. Therap. 286: 1086-1093, 1998.
Browning, K.N., Zheng, Z.L., Kreulen, D.L. and Travagli, R.A. Two populations of sympathetic neurons project selectively to mesenteric artery or vein. In Press, Am. J. Physiol., 1999.