TY - JOUR
T1 - Effect of vagatomy on hyperactivity and increased dopamine turnover induced by intraperitoneal administration of thyrotropin-releasing hormone
AU - Ogawa, Norio
AU - Asanuma, Masato
AU - Kondo, Yoichi
AU - Hirata, Hiroshi
AU - Nakayama, Naoharu
AU - Mori, Akitane
N1 - Funding Information:
Acknowledgements. This work was supported in part by Grants-in Aid for Scientific Research on Priority Areas and Scientific Research from the Ministry of Education, Science and Culture and by grants from the Ministry of Health and Welfare, Japan. The authors are in debt to Dr. Y. Fujiwara, Department of Neuropsychiatry, Okayama University Medical School, for his helpful comments.
PY - 1994/1/7
Y1 - 1994/1/7
N2 - Thyrotropin-releasing hormone (TRH) injected intraperitoneally at doses of 10 mg/kg and 20 mg/kg induced marked hyperactivity in rats. Although regional levels of brain dopamine and its metabolites (DOPAC and HVA) in vagotomized rats did not differ from those in sham-operated controls, the (DOPAC + HVA)/dopamine ratio, an indicator of dopamine turnover, was significantly higher in the nucleus accumbens of TRH-treated sham-operated rats than that in untreated sham-operated controls. TRH injection induced hyperactivity only in sham-operated rats and not in subdiapragmatic bileaterally vagotomized rats. Similarly, bilateral vagotomy completely abolished the TRH-induced increase in dopaminergic turnover in the nucleus accumbens. These results suggest that the dopaminergic system in the nucleus accumbens is involved in hyperactivity induced by TRH, and that TRH mainly affects peripheral receptors. The vagal nerve may be the major pathway from the visceral organs to the brain involved in the etiology of hyperactivity.
AB - Thyrotropin-releasing hormone (TRH) injected intraperitoneally at doses of 10 mg/kg and 20 mg/kg induced marked hyperactivity in rats. Although regional levels of brain dopamine and its metabolites (DOPAC and HVA) in vagotomized rats did not differ from those in sham-operated controls, the (DOPAC + HVA)/dopamine ratio, an indicator of dopamine turnover, was significantly higher in the nucleus accumbens of TRH-treated sham-operated rats than that in untreated sham-operated controls. TRH injection induced hyperactivity only in sham-operated rats and not in subdiapragmatic bileaterally vagotomized rats. Similarly, bilateral vagotomy completely abolished the TRH-induced increase in dopaminergic turnover in the nucleus accumbens. These results suggest that the dopaminergic system in the nucleus accumbens is involved in hyperactivity induced by TRH, and that TRH mainly affects peripheral receptors. The vagal nerve may be the major pathway from the visceral organs to the brain involved in the etiology of hyperactivity.
KW - Dopamine turnover
KW - Hyperactivity
KW - Nucleus accumbens
KW - Thyrotropin-releasing hormone
KW - Vagatomy
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U2 - 10.1016/0006-8993(94)91536-9
DO - 10.1016/0006-8993(94)91536-9
M3 - Article
C2 - 8137153
AN - SCOPUS:0028088928
VL - 633
SP - 167
EP - 170
JO - Molecular Brain Research
JF - Molecular Brain Research
SN - 0006-8993
IS - 1-2
ER -