Progress Report U01 014829
Aims 1 & 2: To test L-NAP and other compounds for
therapeutic potential in preventing alcohol-induced
damage to the cerebellum in a neonatal rat model of 3rdtrimester alcohol exposure during binge drinking
Accomplishments:
1. Vitamin E fails to protect against neontal alcoholinduced cerebellar cell death or functional deficits,
assessed with caspase-3 activation, cell counts and
eyeblink conditioning {published in ACER}
2. L-NAP fails to protect against activation of caspase-3 or
loss of cerebellar Purkinje cells
3. Binge Alcohol on PD 4-9 induces dose-dependent
deficits on trace eyeblink conditioning
Activation of Caspase-3 in Cerebellar
Purkinje Cells (P4)
Progress Report:
Binge Neonatal Alcohol Exposure Impairs
Trace Eyeblink Conditioning
P4-9 Trace vs. LD
350
Adapative CR Max Amp
300
250
UD-D880
UD-T500
200
SI-D880
SI-T500
150
5gkg-D880
5gkg-T500
100
50
0
s1
s2
s3
s4
Sessions
s5
s6
Progress Report
Aim 3: To develop a neonatal mouse model of 3rdtrimester binge exposure and evaluate behavioral
correlates of alcohol-induced damage to hippocampal
formation and limbic cortex
Accomplishments:
• C57BL/6 mice given heavy binge exposure to alcohol
on P7 (2.5 g/kg in each of two injections, 2 hours apart)
• Activation of caspase-3 in caudate, cingulate cortex,
retrosplenial cortex, and hippocampal formation (Zhou)
• P7 binge exposure did not produce effects opposite
that predicted for conditional discrimination reversal
task (eyeblink conditioning
– enhanced responding during discrimination reversal:
impaired inhibitory learning?
Ongoing Study and Renewal Trajectory
Assess 3-day (P7-P9) binge exposure in B6 mice for
enduring consequences of forebrain damage
• Is there hippocampal – frontal cortical targeting?
• Is there age-dependent expression? [compare with P7]
(as seen by Wozniak et al, 2004 with P7 exposure)
– Behavioral Studies (tested at P30 and P70)
• water maze spatial learning
• Trace Eyeblink Conditioning
– Anatomical Studies
• Volumetric and cell count studies of hippocampal formation
(adults tested above)
– Screening for Neuroprotection (with Zhou)
• caspase-3 activation (forebrain)
• Behavior
• Cell counts
What Should the Consortium Basic
Science [Animal Models] Do?
Use two different C57BL/6 mouse models of alcohol
exposure to screen therapeutic agents
Implement animal model behavioral tasks that are directly
applicable to human population
Identify effects in B6 mice; confirm in rat model when
needed
• Prenatal Exposure (liquid diet starting on E7)
 L-NAP protection works for embryonic brain!
 Extend over development; identify mechanism(s) [Miller]
 Need adult testing to screen for long-term protection
• Binge Neonatal Exposure (injection on P7-9)
 Currently comparing effects of P7 vs. P7-9 on “hippocampaldependent” tasks
 Screen potential agents: Vitamin B3 (nicotinamide) may be a
good candidate protective agent (Ierec & Herrera, SfN, 2005)
What Could the Consortium Basic
Science [Animal Models] Do?
• Match assessment tasks in rodents to ones that have
parallels in humans (and can be or are used in the
consortium)
– Eyeblink (trace vs. delay; conditioned inhibition)
– Spatial navigation / spatial memory
– Fear / avoidance conditioning (behavioral & autonomic)
– Response to novelty
– Impulsivity? delay discounting task (insensitivity to
future or unpredictable consequences)
– Circadian regulation?
– HPA regulation / stress reactivity (CORT)
What Could the Consortium Basic
Science [Animal Models] Do?
• L-NAP Protection against prenatal exposure deficits in B6
Mouse Model (liquid diet beginning on E7)
– Behavioral Studies (testing L-NAP protection)
– Develop Behavioral Screening Battery for mice (in collaboration
with Stanton/JHU Center for Neurogenetics)
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•
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Spatial navigation & spatial working memory
Eyeblink Conditioning: Trace vs. Delay
Eyeblink Condiitioning: Conditioned Inhibition
Fear conditioning (contextual vs. signaled)
Fear conditioning (trace vs. delay)
Activity and response to novelty
Prepulse inhibition of acoustic startle
Tests of impulsivity (delay discounting task)?
– Anatomical Studies (adults tested above) with Zhou
– Find mechanisms of protection
What Could the Consortium Basic
Science [Animal Models] Do?
•
Pursue agents that may prevent neonatal damage
– Screening approach : outcome measures matched to
consortium
– Candidate therapeutics in depth (e.g., vitamin B3)
•
Pursue post-treatment interventions that may help ameliorate
the neonatal alcohol-induced damage (esp. targeting
cerebellar, hippocampal, or frontal cortical function)
– Potential interventions
• Exercise, targeted training, other “enrichment”
(currently outside CIFASD)
• Choline Supplementation (currently outside CIFASD)
• Pharmacological treatment (diffusely done across the
field)
•
Biomarkers!