Prolonged methamphetamine exposure during a critical period in neonatal Sprague-Dawley rats does not exacerbate egocentric and allocentric learning deficits but increases reference memory impairments.

Prolonged methamphetamine exposure during a critical period in neonatal Sprague-Dawley rats does not exacerbate egocentric and allocentric learning deficits but increases reference memory impairments. Int J Dev Neurosci. 2020 Feb 11;: Authors: Williams MT, Amos-Kroohs RM, Vorhees CV Abstract Children exposed to methamphetamine (MA) in utero have cognitive deficits. MA administration in rats for 5-10 days between postnatal day (P)6-20 produces cognitive deficits. The purpose of this study was to determine if extending MA administration by 5 days within P6-20 would exacerbate allocentric (Morris water maze) and egocentric (Cincinnati water maze) learning deficits. Sprague-Dawley female and male offspring (split-litter design) were administered saline (SAL) or MA (10 mg/kg) four times daily from P6-20 to create four groups: (1) SAL from P6-20, (2) MA from P6-20 (MA6-20), (3) MA from P6-15 (MA6-15), or (4) MA from P11-20 (MA11-20); the latter groups received saline on days they did not receive MA. Egocentric, allocentric, and conditioned freezing tests began on P60. The MA6-15 and MA6-20 groups showed egocentric deficits, all MA groups had allocentric deficits but no differences in conditioned freezing compared with SAL controls. The MA6-15 and MA6-20 groups had similar deficits in learning and memory that were larger than in the MA11-20 group. Learning in both mazes was sex dependent, but no interactions with MA were found. The data dem...
Source: International Journal of Developmental Neuroscience - Category: Neuroscience Authors: Tags: Int J Dev Neurosci Source Type: research