Gordon A. Barr
Current Areas of Research:
Developmental Psychobiology. The general topic of study by this lab is how the development of neural and other physiological processes result in behavioral and physiological maturation. To that end, we study behavior within a developmental framework and examine how the maturation of biological systems that might cause those changes. This approach lends itself to the use of a variety of behavioral, anatomical, pharmacological, and genetic methods, all of which can be brought to bear on the biological question of interes t. Below are the areas of long standing interest.
Opiate abstinence. Large numbers of human infants are exposed in utero to illicit opiate drugs such as heroin and to prescribed opiates such as methadone. It is therefore important to understand the effects of acute and chronic exposure to drugs such as these on the immature organism. A necessary step in defining the long term effects of drug exposure early in development is to describe fully how the drug acts on neurobehavioral systems in the neonate. We have found that the infant undergoes a distinct opiate withdrawal, but that the signs and symptoms experienced by the neonate differ from those suffered by the adult. Nonetheless, the infant in abstinence shows developmentally appropriate behavioral signs of withdrawal, increased crying and a negative affective state. We are currently working to define the neural substrates of opiate withdrawal in the infant and relating that circuitry to known neural involvement in the adult animal. This knowledge will provide the basis for a rational treatment of opiate withdrawal in the human infant.
Nociception. The issue of how noxious stimuli are processed at various levels of the neuroaxis has been the subject of intense study for decades and significant progress has been made in our understanding of how noxious sensations are perceived, processed and dampened. Yet little is known of how pain processing differs between immature and adult organisms. The question of whether or not infants even experience pain has been controversial. Not long ago the prevailing medical opinion was that human infants did not perceive pain due to the immature state of their nervous system, and in particular the lack of myelination of axons. This assumption led directly to the inappropriate withholding of analgesics for painful surgical treatments. Recent studies have shown that the requisite pathways for the transmission of pain from the periphery to the central nervous system develop perinatally, but a detailed understanding of how these input systems become organized is still lacking. Understanding how pain sensation develops is a necessary first step in the development of appropriate therapeutic interventions to alleviate pain and suffering in the human neonate.
Analgesia. The problems of how to provide safe and effective analgesia for human infants are difficult because a major class of analgesic drugs, the opiates, act differently in the infant patient than they do in the adult patient. As a consequence analgesics are not used regularly for the alleviation of pain for human neonates in intensive care. Furthermore, the relationship of unwanted side effects to therapeutic effects changes with age. Classically, opiates have been known to induce analgesia by acting on the central nervous system and a major part of our work is aimed at understanding how those neural systems function during early development. The full description of changes in nociception, opiate induced antinoception, opioid peptide and receptor regulation will provide important information on the development of opiate induced pain relief in both human infants and adults.
Transgenics. We are particularly interested in establishing collaborations to study "knock out" mice to establish how defined genetic alterations can change function. This is a fruitful approach in development where the physiology of the "knock out" may change over time when the gene product is normally required at different stages of development. We are particularly interested in the study of inducible "knock outs" since the ability to knock out the gene at different stages of development will provide important clues as to the function of that gene during normal maturation. We are interested in hearing from any investigator interested in nervous system function and who wishes to collaborate. The goal is to develop fundable projects from this collaboration. Please contact Gordon Barr, Ph.D., if interested. gbarr@shiva.hunter.cuny.edu
Selected Publications: