Air Quality Criteria for Lead Volume II of II - (NEPIS)(EPA) - US ...

AX5-22
Subject
Rat, female,
22 wks
Rat
Wistar
Rat, LE,
postweaning
Rat, LE, male
Postweaning
Rat, LE, male
Postweaning
Rat, LE, male
Postweaning
Exposure
Protocol
Table AX5-3.4. Summary of Key Studies on Neurobehavioral Toxicity
Peak Blood Pb
or [Pb] Used Observed Effects Reference
75 or 300 ppm Pb(Ac) 2 39 µg/dL Significantly impaired on the alteration task with variable intertrial delays. Alber and Strupp
(1996)
750 ppm Pb(Ac) 2 15 µg/dL Pb-induced deficits in AAL in rats exposed to Pb either during pre-weaning
or pre- and postweaning: postweaning-only exposure caused reduced deficits
in AAL.
50 ppm Pb(Ac)2 15.1 µg/dL Quinpirole at 0.05 mg/kg reversed the effects of Pb on FI performance;
eticlopride had no effect on response rates in Pb-treated animals.
50 or 150 ppm Pb for 3 mo 10.8 and
28.5 µg/dL
50 or 150 ppm Pb for 3 mo 9.7 and
26.2 µg/dL after
3 and 7 mo
50 or 150 ppm Pb for 3 mo 16.0 and
28.0 µg/dL
FR: 150-ppm rats—significantly higher response rates and component resets
than the low dose group and controls. Waiting behavior: wait time was lower
in both treated groups. 150-ppm rats—increased number of reinforcers and a
higher response to reinforcement ratio than low dose and controls.
D2 agonist quinpirole reversed the Pb-induced effects on FR-response rate,
FR resets, wait reinforcers, and wait time.
Altmann et al.
(1993)
Areola and
Jadhav (2001)
Brockel and
Cory-Slechta
(1998)
Brockel and
Cory-Slechta
(1999a)
No Pb-induced effects on sustained attention. Brockel and
Cory-Slechta
(1999b)
Rat, SD, adult 500 ppm Pb(Ac)2 20.9 µg/dL Chronic Pb exposure attenuated the reinforcing effect of brain stimulation. Burkey and
Nation (1994)
Rat, SD 0.2% Pb(Ac) 2 during gestation
and lactation, postweaning
only, or continuously
PND 56: 3.8,
25.3, and
29.9 µg/dL
No Pb-associated effects in learning performance with just maternal or
postweaning exposure. Continually exposed rats tended to avoid less
frequently and in two-way active avoidance training, did not respond
more frequently.
(Chen et al.
(1997a)