Effect of injection of thyrotropin-releasing hormone into nucleus accumbens on pain discharges in nucleus parafascicularis of the thalamus in rats.
Glass microelectrode recording method was used to investigate the effect of injection of thyrotropin-releasing hormone (TRH) into nucleus accumbens, nucleus amygdalae or nucleus caudatus on unit discharges from pain-excitation neurons (PEN) in nucleus parafascicularis of the thalamus in rats. The results showed that: 1) Injection of TRH into the nucleus accumbens resulted in a significant inhibition of pain discharges from PEN in nucleus parafascicularis, while injection of TRH into nucleus amygdalae, nucleus caudatus exerted no significant effect. 2) Pretreatment with atropine abolished the above-mentioned effect of TRH. 3) Pretreatment with haloperidol also abolished the above-mentioned inhibitory effect of TRH. 4) Pretreatment with naloxone, propranolol or phentolamine did not affect the inhibitory effect of TRH. These results suggested that nucleus accumbens might be a special area in response to TRH and the effect of TRH seems to be involved in both cholinergic M-receptor and dopaminergic receptor.
Nie
Z G
ZG
Department of Physiology, Tongji Medical University, Wuhan.
Liu
Z Y
ZY
D000818:Animals; D004594:Electrophysiology; D005260:Female; D008032:Limbic System / Q000502:physiology; D008297:Male; D008845:Microinjections; D009619:Nociceptors / Q000502:physiology*; D009714:Nucleus Accumbens / Q000502:physiology; D010146:Pain / Q000503:physiopathology*; D051381:Rats; D011919:Rats, Inbred Strains; D012684:Sensory Thresholds; D013787:Thalamic Nuclei / Q000502:physiology*; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology*
D013973:Thyrotropin-Releasing Hormone