Ph.D. (M.I.T.) F.R.S.C.
Ophthalmology Research Group
Graduate Program in Neuroscience
Tel: (604) 822-1388
Fax: (604) 822-0361
Mail: 2211 Wesbrook Mall,
Canada, V6T 2B5
Our lab's research interests center around molecular
mechanisms of neuronal plasticity and cell death. In addition, we study the mechanisms
by which the visual and auditory systems process sensory information, and the normal
and abnormal development of these capabilities.
- Gene therapy for the nervous system. We are using Herpes simplex
viral vectors to insert neuroprotective and other genes into neurons that are at
risk in several different neurodegenerative disorders, including models for
Huntington disease, stroke and glaucoma. The goal is to use neuronal gene therapy
to develop new strategies for the treatment of neurological diseases.
- Studies of the mechanism of the critical period: We have
found that early in postnatal life, there is a
critical period during which the visual cortex
experiences strong neuroplasticity. In adult
animals, this plasticity normally wanes. We are
using techniques such as in situ
hybridization, immunohistochemistry, brain slice
electrophysiology, and molecular biological
techniques (including PCR and subtractive
hybridization), to understand the pattern of
macromolecules that are expressed selectively in
the developing visual cortex, in order to
determine the molecular mechanisms that underlie
this critical period. We are also using growth
factor therapy and various forms of gene therapy
(see above) to try to reinstate the critical
period in adult animals, to provide for new
therapeutic approaches to long-standing diseases
of early childhood.
- We are using Herpes simplex viral vectors to insert
genes into neurons that may be defective in
expressing certain transmitters or receptors, or
into neurons which have stopped expressing
particular genes (for instance, after the
critical period has ended). The long-term goal
is to use this method to develop new therapies
for neurological disease characterized by
deficient production of enzymes, transmitters,
receptors, etc., and also to try to reinstate
the critical period mechanisms that have been
previously switched off.
- Neurotransmitter receptors are an important
information-regulating device within the
cerebral cortex. We are studying the
localization, development, and function of over
a dozen neurotransmitter receptors in the
cerebral cortex. We are trying to understand why
so many neurotransmitters appear to be
associated with different classes of cortical
cells, In addition, we are building on earlier
observations that the organism's exposure
history affects the development and distribution
of these neurotransmitter receptors, to study
the role of these receptors and their second
messengers in development and plasticity.
- Studies of the sensory organization of the visual and
auditory cortex: We and others have found that
the cortical surface contains a distorted map of
the sensory world. In addition, cortical neurons
with different properties are laid out in banded
or other regular patterns across this surface.
Using multiple-electrode maps, voltage-sensitive
dyes, and video microscopy techniques, we are
studying the pattern of cortical activation
ssociated with particular visual and auditory
stimuli, and trying to determine whether certain
forms of visual stimulation result in regular
patterns, or efficient flow of neural activity,
across the cortical surface.
(1994). Mechanisms of brain development and their
role in health and well-being. Daedalus 123:155-165.
Jia WG, McDermott
M, Goldie J, Cynader M, Tan J, Tufaro F (1994).
Selective destruction of gliomas in immunocompetent
rats by thymidine kinase-defective Herpes simplex
virus type 1. J National Cancer Inst 86:1209-1215.
Prasad S, Cynader
M (1994). Identification of cDNA clones expressed
selectively during the critical period for visual
cortex development by subtractive hybridization.
Brain Research 639:73-84.
Dyck RH, Cynader
MS (1993). Autoradiographic localization of
serotonin receptor subtypes in cat visual cortex:
transient regional, laminar, and columnar
distributions during postnatal development. J Neurosci 13:4316-4338.