Corticotropin-releasing factor receptor type 1, but not type 2, in the ventromedial hypothalamus modulates dopamine release in female rats.
Corticotropin-releasing factor (CRF) plays an important role in stress responses and is mediated through two subtypes of receptors, CRF receptor type 1 (CRFR1) and CRF receptor type 2 (CRFR2). Each CRF receptor might have a different function through several neurotransmitter systems; however, the mechanism remains unclear. To clarify the role of each receptor in dopamine (DA) metabolism, we measured the change of extracellular concentrations of DA and the metabolites in the ventromedial hypothalamus (VMH) that played important roles in the stress response of freely moving female rats in response to the direct administration of comparative CRFR1 selective agonist, CRF, or CRFR2 selective agonist, Urocortin II (Ucn II), into the brain region. Administration of 10 microg CRF increased extracellular concentrations of DA compared with 2 microg CRF immediately after injection, and this effect was not observed after 60 min of 10 microg CRF injection. On the other hand, this change did not always occur after Ucn II administration. These results suggest that the activation of CRFR1, but not CRFR2, modulates the release of DA in VMH.
Muramatsu
Tomohiro
T
Department of Neuropsychiatry, Osaka City University Medical School, 1-4-3 Asahi-machi, Abeno-ku, Osaka City, Osaka 545-8585, Japan. muramatsut@med.osaka-cu.ac.jp
Inoue
Koki
K
Iwasaki
Shinichi
S
Yamauchi
Tsuneo
T
Hayashi
Teruaki
T
Kiriike
Nobuo
N
D015102:3,4-Dihydroxyphenylacetic Acid / Q000032:analysis; D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D006719:Homovanillic Acid / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D018019:Receptors, Corticotropin-Releasing Hormone / Q000502:physiology*; D054832:Urocortins; D014697:Ventromedial Hypothalamic Nucleus / Q000378:metabolism*; D000099052:CRF Receptor, Type 1
C101531:CRF receptor type 2; D018019:Receptors, Corticotropin-Releasing Hormone; D054832:Urocortins; D015102:3,4-Dihydroxyphenylacetic Acid; D000099052:CRF Receptor, Type 1; D003346:Corticotropin-Releasing Hormone; D004298:Dopamine; D006719:Homovanillic Acid