David R. Riddle, Ph.D.
Assistant Professor
(University of Michigan, 1990)

We investigate the regulation of axonal and dendritic growth and the formation and maintenance of neuronal circuits in the developing, adult and aging central nervous system. Studies of the developing cerebral cortex focus on dendritic growth and activity-dependent modulation of circuit development and refinement. Studies of the aging brain are examining the effects of Insulin-like Growth Factor I on neuronal stem cells, neurogenesis and neuronal differentiation, testing the potential of IGF-I to ameliorate cognitive deficits associated with aging. The laboratory uses both in vivo and in vitro models and applies a variety of anatomical, cell-biological and physiological methods, including confocal microscopy, quantitative morphology, particle-mediated gene transfer (biolistics), immunocytochemistry, and cell and tissue culture.

 Selected Publications:

Riddle DR, Lo DC, Katz LC (1995) NT-4 mediated rescue of lateral geniculate neurons from effects of monocular deprivation. Nature 378(6553):189-192.

Purves D, White LE, Riddle DR (1996) Is neural development Darwinian? Trends in Neurosci 19: 460-464.

Riddle DR, Katz LC, Lo DC (1997) Focal delivery of neurotrophins into the central nervous system using fluorescent latex microspheres. Biotechniques 23: 928-937.

Niblock MM, Brunso-Bechtold JK, Riddle DR (2000) Insulin-like growth factor I stimulates dendritic growth in primary somatosensory cortex. J Neurosci 20(11): 4165-4176.

Niblock MM, Brunso-Bechtold JK, Riddle DR (2000) Laminar variation in neuronal viability and trophic dependence in neocortical slices. Journal Neuroscience Research 65: 455-462.

Lichtenwalner RJ, Forbes ME, Bennett SA, Lynch CD, Sonntag WE, and Riddle DR (2001) Intracerebroventricular infusion of insulin-like growth factor-1 ameliorates the age-related decline in hippocampal neurogenesis.  Neuroscience 107: 603-613.

Sonntag WE, Brunso-Bechtold JK, and Riddle DR  (2001)  Age-related decreases in growth hormone and insulin-like growth factor (IGF)-1:  implications for brain aging.  Journal of Anti-Aging Medicine, 4:311-330.

Grill JD and Riddle DR (2002) Age-related and laminar-specific dendritic changes in the cingulate cortex.  Brain Res, 937: 8-21.

Riddle, DR, Sonntag WE, and Lichtenwalner, RJ (2003) Microvascular plasticity in aging. Ageing Research Reviews 2(2): 149-168.

E-mail: driddle@wfubmc.edu