Faculty Collaboration Database

Adverse effect of the combination of hypothyroidism and chronic psychosocial stress on hippocampus-dependent memory in rats. Behav Brain Res 2004 Nov 05;155(1):77-84

Date

08/25/2004

Pubmed ID

15325781

DOI

10.1016/j.bbr.2004.04.003

Scopus ID

2-s2.0-4344651290 (requires institutional sign-in at Scopus site)   107 Citations

Abstract

Both hypothyroidism and stress interfere with cognitive function in patients. This study examined the effect of hypothyroidism and stress on hippocampus-dependent learning and memory in rats using the novel radial arm water maze (RAWM), which measures spatial working memory. Hypothyroidism was accomplished by thyroidectomy and 2 weeks later a form of intruder stress was used as the chronic psychosocial stressor. After 4-6 weeks of stress, rats were trained to learn (during the acquisition phase; four trials) and then remember (during two memory test trials occurring 15 and 120 min after the acquisition phase) the within-day location of a hidden escape platform, which was in different arm every day. The number of errors (entry into arms other than the platform arm) was noted. Within-day learning of the platform location was largely unaffected by the experimental manipulations, indicating that rats in all groups were equally capable of finding the platform to escape from the water with similar numbers of errors (P > 0.005). The number of days a rat took to reach a criterion (DTC; a maximum of one error in three consecutive days) indicated that chronic stress or hypothyroidism, alone, resulted in a mild impairment of spatial memory, and the combination of chronic stress and hypothyroidism resulted in a more severe and long-lasting memory impairment. The data indicated that the combination of stress and hypothyroidism produced more deleterious effects on hippocampal function than either chronic stress or hypothyroidism alone.

Author List

Gerges NZ, Alzoubi KH, Park CR, Diamond DM, Alkadhi KA

Author

Nashaat Gerges PhD Chair, Professor in the School of Pharmacy Administration department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Behavior, Animal
Escape Reaction
Hippocampus
Hypothyroidism
Male
Maze Learning
Memory Disorders
Rats
Rats, Wistar
Stress, Psychological
Thyroidectomy
Time Factors