CORTEX TRANSPLANTATION

Project: Research project

Description

Previous work has demonstrated survival of peptidergic,
diaphorase, and pyramidal neurons in fetal cortex transplants
which connect to host cortex and subcortical structures. This
proposal addresses the question of whether these transplants are
functional, and if so, whether this is due to appropriate
connections or to trophic interactions between host and
transplant. To answer whether transplants are functional, rats
are first trained to perform a forelimb motor task. One week
after lesioning forelimb motor cortex, one group receives fetal
frontal cortex, one receives fetal cerebellar, and one receives
gelfoam implants. The motor behavior of each transplanted group
is compared to the gelfoam implanted controls. Following this,
transplants are removed. It is hypothesized that forelimb motor
function will deteriorate following removal of functional
transplants. Secondly, it will be determined whether adult host
brain thalamic connections to fetal parietal cortex transplants are
functional. The whisker sensory barrelfield of adult rats is
removed, and fetal parietal cortex transplanted into the cavity.
Later, the vibrissae contralateral to the transplants are
stimulated. 2-deoxyglucose is injected and the resting and
stimulated transplant glucose metabolic rates determined using a
double label autoradiographic method. Transplants with
functional host connections should be metabolically activated
during the whisker sensory stimulation. Lastly, trophic effects of
fetal cortical transplants on neonatal host thalamus will be
examined. One week after removal of the frontal cortex of
newborn rats, either fetal frontal cortex, fetal cerebellum, fetal
parietal cortex, minced fetal frontal cortex, or gelfoam is
transplanted into lesion cavities. Since marked host thalamic
atrophy normally occurs ipsilateral to fetal frontal cortex lesions,
this will determine which transplants ameliorate the atrophy.
Host-transplant connections are examined in the above
experiments to determine which effects correlate with formation
of connections. Cortex injury due to strokes, head trauma, and other diseases can
lead to devastating, permanent motor and sensory impairments in
humans. The data from this proposal will help determine whether
fetal transplants might offer some hope for treating such deficits.
StatusFinished
Effective start/end date9/1/878/31/90

Funding

  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health

Fingerprint

Transplantation
Transplants
Frontal Lobe
Vibrissae
Forelimb
Absorbable Gelatin Sponge
Parietal Lobe
Hope
Pyramidal Cells
Deoxyglucose
Motor Cortex
Thalamus
Craniocerebral Trauma
Cerebellum
Atrophy
Stroke
Glucose
Wounds and Injuries

ASJC

  • Medicine(all)
  • Neuroscience(all)