Farel - Research

Neural Development and Regeneration

D1 labeling of hindlimb nerves in an E12 fetus. The upper panel shows a fluorescence image of labeled axons. The bottom panel is a digitally enhanced version to show that the axons reach the distal tip of the limb, even at this very early stage of development.

Using both mammalian and non-mammalian species, we have evidence that neuron number increases in many regions of the nervous system as juveniles attain adult size. Neuron proliferation has been ruled out as contributing to the increase in neuron number. Instead, a pool of committed, but incompletely differentiated immature neurons complete their differentiation during normal postnatal development, presumably in response to the demands of increasing body size. Such findings are of exceptional interest to developmental neurobiologists for two reasons. First, neuron addition in juveniles implies that mechanisms thought to be restricted to narrow windows of embryonic development may in fact persist through the life of the animal. Second, if developmental mechanisms of neuron addition persist into postnatal life, then the possibility of enlisting these mechanisms to restore neurons lost to injury or disease becomes more salient.

We are currently investigating how neurons are recruited during growth of the juvenile. We are also pursuing studies that demonstrate that differentiation of these immature neurons can occur following injury to neighboring regions of the nervous system, perhaps contributing to functional recovery following injury or disease. 

Paul Farel teaches in MS1 Block 3 and serves as Chair of the Health Sciences Library Advisory Committee. He is also a member of the Faculty Grievance Committee.