Associate Professor, Center for Neuroscience University of Pittsburgh Phone: (412) 624-6995 Fax: (412) 624-9198 Email: card@brain.bns.pitt.edu Individual Website: http://www.pitt.edu/~neurosci/faculty/card.html

Ph.D., Wayne State University

Research Interests

My research interests fall into two basic categories. A long-standing focus of the laboratory is definition of the functional organization of neural circuits involved in the control of behavioral state and autonomic function. The primary objective of these studies is to define the synaptic organization and chemical phenotype of the central networks that mediate these essential regulatory functions. Characterization of the plasticity and developmental assembly of these circuits is a related component of these analyses. The second focus of the laboratory is the development of tools for transneuronal tracing of neural circuits. This effort, which is fundamental to the goals of our investigation of neural circuitry, incorporates a mechanistic approach. It is supported by my recent successful NIH application with Dr. Peter Strick to establish a National Center for Neuroanatomy with Neurotropic Viruses at the University of Pittsburgh. Dr. Strick and I serve as Co-Directors of this Center.

Current studies focus upon circuitry through which the brain stem, hypothalamus and limbic forebrain control autonomic function. Toward this end, we have used neurotropic viruses to define the neural circuits that modulate sympathetic and parasympathetic components of the autonomic nervous system. These studies, which examined the central transport of virus from autonomic targets (e.g., stomach, spleen, kidney), have provided important insights into the way in which the nervous system controls autonomic outflow. Nevertheless, the synaptology that permits the central autonomic network to exert integrated regulatory control over autonomic outflow is only understood in general principles. Our efforts are devoted to defining the detailed synaptology through which the central autonomic network exerts regulatory oversight over peripheral autonomic function.

To define the functional organization of central circuits that modulate autonomic function we are developing novel approaches that permit functional microdissection of the network. These include the use of lentivirus vectors to define the efferent projections of phenotypically defined neurons and conditional replication of pseudorabies virus (PRV). Our conditional replication studies build upon the proof-of-principle approach developed by DeFalco and colleagues and published in Science in 2001. It involves the use of a recombinant strain of PRV that is dependent upon the presence of the protein cre recombinase (CRE) to become replication competent. Since cre recombinase is not present in the mammalian genome, a means of reliable delivery of the transgene is a rate-limiting step to application of the technology. DeFalco and colleagues generated a transgenic mouse in which cre recombinase was differentially expressed in NPY neurons. Our approach has been to develop vectors to deliver CRE to targeted populations of neurons. We have shown that restricted expression of CRE can be achieved in catecholamine neurons by placing CRE expression under the control of a synthetic dopamine-beta-hydroxylase promoter. In developing this vector we incorporated a GRP reporter gene as a mechanism of unambiguously determining that the CRE transgene was being expressed. An unexpected outcome of this approach was the demonstration that the GFP reporter fills both the somatodendritic and axonal compartments of catecholamine neurons. We have exploited this novel technology to define the efferent projections of brainstem catecholamine neurons involved in cardiovascular regulation and are applying it for anterograde tracing of projection fields of other catecholamine neurons. Our first study applying this novel approach was published this year in the Journal of Comparative Neurology.

The collective intent of my research program is to pursue an integrated experimental plan that develops knowledge of the mechanisms of viral invasiveness and then exploits that knowledge for transneuronal analysis of the functional organization of neuronal circuits.

Recent Publications

• Card JP, Sved JC, Craig B, Raizada M, Vazquez J, Sved AF: Efferent projections of rat rostroventrolateral medulla C1 catecholamine neurons: Implications for the central control of cardiovascular regulation. J Comparative Neurology 499: 840-859, 2006.
• Card JP, Levitt P, Gluhovsky M, Rinaman L: Early experience modifies the postnatal assembly of autonomic emotional motor circuits in rats. J Neurosci 25: 9102-9111, 2005.

• Aston-Jones G, Zhu Y, Card JP: Numerous GABAergic afferents to locus coeruleus in the pericoerulear dendritic zone: Possible interneuronal pool. J Neurosci 24: 2313- 2321, 2004.

• Cano G, Card JP, Sved AF: Dual viral transneuronal tracing of central autonomic circuits involved in the innervation of the two kidneys in rat. J Comp Neurol 471: 462-481, 2004.
• Cano G, Passerin AM, Schlitz JG, Card JP, Morrison SF, Sved AF: Anatomical substrates for the central control of sympathetic outflow to intercapsular adipose tissue during cold exposure. J Comp Neurol 460: 303-326, 2003.
• Card JP: Pseudorabies virus neuroinvasiveness: A window into the functional organization of the brain. Advances in Viral Research, volume 56, Neurovirology, Viruses and the Brain. Academic Press: 39-71, 2001.

• Rinaman L, Levitt P, Card JP: Progressive postnatal assembly of limbic-autonomic circuits revealed by central transneuronal transport of pseudorabies virus. J Neurosci 20: 2731-41, 2000.
• Card JP, Enquist LW, Moore RY: The progression of viral infection through multisynaptic circuits innervating rat striatum is dependent upon viral concentration and terminal field density. J Comp Neurol 407: 438-452, 1999.
• Card JP: Exploring brain circuitry with neurotropic viruses: New horizons in neuroanatomy. Anat Rec (The New Anatomist) 253: 176-185, 1998.
• Card JP, Levitt P, Enquist LW: Different patterns of neuronal infection after intracerebral injection of two strains of pseudorabies virus. J Virol 72: 4434-41, 1998.

• Card JP: Pseudorabies virus replication and assembly in rodent CNS. In ViralVectors: Tools for Study and Genetic Manipulation of the Nervous System, MG Kaplitt and AD Loewy, eds., Academic Press, San Diego: 319-347, 1995.