Effect of dopamine on the hypothalamo-pituitary-adrenocortical system after injection in the nucleus raphe dorsalis.
Dopamine (DA) injected into the dorsal raphe nucleus (DRN) increased plasma corticosterone (PCS) level as well as serotonin (5-HT) content in the mesencephalon and hippocampus 30 min after the administration. At the same time, 5-HT content of the hypothalamus was decreased. A stress applied 2 min after the injection elevated PCS level but diminished hypothalamic 5-HT content in control, but not in DA-treated animals. PCS level and 5-HT content of the hypothalamus in DA-treated + stressed animals did not differ from the values found in DA-treated rats, but mesencephalic and hippocampal 5-HT content did not increase. It is concluded that DA injected into the DRN suppresses the response to stress of the hypothalamo-pituitary-adrenocortical system.
Fekete
M
M
Institute of Physiology, University Medical School, Pécs, Hungary.
Hartmann
G
G
Zakirov
D
D
Halvax
L
L
Lissák
K
K