Combination of hypothyroidism and stress abolishes early LTP in the CA1 but not dentate gyrus of hippocampus of adult rats. Brain Res 2001 Dec 20;922(2):250-60
Date
12/18/2001Pubmed ID
11743957DOI
10.1016/s0006-8993(01)03181-xScopus ID
2-s2.0-0035924361 (requires institutional sign-in at Scopus site) 148 CitationsAbstract
Clinical experience suggests that both hypothyroidism and stress interfere with mental concentration and memory. This electrophysiological study examined the effect of hypothyroidism and stress, separately or combined, on long-term potentiation (LTP), a widely accepted cellular model for learning and memory. Measurements of early LTP (E-LTP) were carried out in the hippocampus of urethane-anesthetized adult Wistar rats. Hypothyroidism was achieved by thyroidectomy, and the 'intruder' stress was used as a model of chronic psychosocial stress. Stimulating electrodes were placed in the left CA3 region and right angular bundle and a recording electrode was placed in the right CA1 or the dentate gyrus (DG). The results showed that in the CA1 region of the hippocampus, hypothyroid or stress partially blocked E-LTP. However, when hypothyroidism and stress were combined, they eliminated E-LTP. In contrast, no significant change in E-LTP was seen in the DG of the three groups of rats. These results suggest that impaired memory because of hypothyroidism or stress may be related to impairment of the E-LTP in the Schaffer collateral synapses but not of that of the perforant path synapses.
Author List
Gerges NZ, Stringer JL, Alkadhi KAAuthor
Nashaat Gerges PhD Chair, Professor in the School of Pharmacy Administration department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsBody Weight
Corticosterone
Dentate Gyrus
Electric Stimulation
Excitatory Postsynaptic Potentials
Hypothyroidism
Long-Term Potentiation
Male
Memory Disorders
Perforant Pathway
Rats
Rats, Wistar
Stress, Physiological
Synapses
Synaptic Transmission
Thyroidectomy
Thyroxine
