Electroconvulsive seizures modulate levels of thyrotropin releasing hormone and related peptides in rat hypothalamus, cingulate and lateral cerebellum.
We have studied the neuroanatomic extent of electroconvulsive (ECS)-responsive prepro-TRH and TRH-related gene expression and its possible interaction with forced swimming. Young adult male Wistar rats were treated in a 2x2 Latin square protocol of swimming, no swimming, three daily ECS or sham ECS. Sixteen different brain regions were dissected and immunoreactivity measured for TRH (pGlu-His-Pro-NH(2)); TRH-Gly, a TRH precursor; Ps4, a prepro-TRH-derived TRH-enhancing decapeptide, and EEP (pGlu-Glu-Pro-NH(2)). ECS, in addition to elevating TRH-immunoreactivity (TRH-IR), TRH-Gly-IR, Ps4-IR and EEP-IR levels in the limbic regions, as we have previously reported, also significantly increased Ps4-IR levels in hypothalamus, posterior cingulate and lateral cerebellum, and increased TRH-Gly-IR levels in hypothalamus. Interestingly, the combination of ECS and swimming significantly reduced the levels of TRH-Gly-IR in the anterior cingulate compared to the sham ECS-no swim group. The combined use of high-pressure liquid chromatography and the EEP radioimmunoassay (RIA) revealed that pGlu-Tyr-Pro-NH(2) and/or pGlu-Phe-Pro-NH(2) occur in amygdala, anterior cingulate, frontal cortex, entorhinal cortex, lateral cerebellum and striatum and make a substantial contribution to the EEP-IR and TRH-IR. We conclude that ECS can alter the expression and secretion of TRH-related peptides in the hypothalamus, cingulate and lateral cerebellum. Such effects have not previously been reported in these limbic and extra-limbic regions which are increasingly implicated in the autonomic, behavioral and volitional changes which accompany severe depression and its treatment.
Pekary
A E
AE
Research, VA Greater Los Angeles Healthcare System, Los Angeles, CA 90073, USA. epekary@ucla.edu
Meyerhoff
J L
JL
Sattin
A
A
D000818:Animals; D002531:Cerebellum / Q000166:cytology / Q000378:metabolism*; D004565:Electroconvulsive Therapy; D004597:Electroshock; D006179:Gyrus Cinguli / Q000166:cytology / Q000378:metabolism*; D007031:Hypothalamus / Q000166:cytology / Q000378:metabolism*; D008297:Male; D009124:Muscle Proteins / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000378:metabolism*; D013312:Stress, Physiological / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D013973:Thyrotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000378:metabolism*
D009124:Muscle Proteins; C081025:PS4 protein, Oryctolagus cuniculus; D013973:Thyrotropin-Releasing Hormone; C040476:thyrotropin-releasing hormone, Gly; C059697:pyroglutamyl-glutamyl-proline amide; D011761:Pyrrolidonecarboxylic Acid