Monoaminergic regulation of the levels of beta-endorphin-like immunoreactivity (beta-ENDi) in rat hypothalamic nuclei.
To examine the role of monoamines in regulating beta-endorphin levels in discrete brain nuclei, the levels of beta-endorphin-like immunoreactivity (beta-ENDi) were determined in the hypothalamic nuclei of rats 2 h after they were treated with monoaminergic drugs. Sulpiride decreased the levels of beta-ENDi in the nucleus paraventricularis, nucleus arcuatus and median eminence. Domperidone decreased the levels of beta-ENDi in the nucleus aracuatus and median eminence. L-DOPA increased the levels of beta-ENDi in the nucleus anterior hypothalami and median eminence. Phenylephrine or prazosine did not alter the levels of beta-ENDi. Yohimine decreased the levels of beta-ENDI in the nucleus anterior hypothalami. Isoproterenol increased the levels of beta-ENDi in the nucleus arcuatus, and propranolol reversed this effect. These results suggest that dopamine and noradrenaline (via beta-adrenoceptors) may regulate beta-endorphinergic neurons in the rat hypothalamus.
Nohtomi
A
A
Department of Neurophsychiatry, Faculty of Medicine, Kysuchu University, Fukuoka, Japan.
Itoh
M
M
Yufu
N
N
Fukahori
M
M
Kawasaki
H
H
D000818:Animals; D001337:Autonomic Agents / Q000494:pharmacology*; D015306:Biogenic Monoamines / Q000502:physiology*; D004294:Domperidone / Q000494:pharmacology; D007031:Hypothalamus / Q000032:analysis / Q000187:drug effects*; D008297:Male; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D011941:Receptors, Adrenergic / Q000187:drug effects / Q000502:physiology; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology; D013469:Sulpiride / Q000494:pharmacology; D001615:beta-Endorphin / Q000032:analysis* / Q000502:physiology
D001337:Autonomic Agents; D015306:Biogenic Monoamines; D011941:Receptors, Adrenergic; D011954:Receptors, Dopamine; D004294:Domperidone; D001615:beta-Endorphin; D013469:Sulpiride