Adrenocorticotropin and growth hormone secretions after intracerebroventricular administration of neostigmine in rats: their relationships to hypothalamic monoaminergic neuronal activities.
Serum adrenocorticotropic hormone (ACTH) and growth hormone (GH) concentrations were assessed simultaneously with hypothalamic neuronal activities of norepinephrine (NE), dopamine (DA), and serotonin (5-HT) 60 min after the third cerebroventricular administration of neostigmine (a cholinesterase inhibitor) in awake rats. Serum ACTH and GH concentrations were significantly increased and decreased, respectively. Neostigmine caused significant increases in hypothalamic NE and DA activities and a significant decrease in hypothalamic 5-HT activity. The reciprocal changes of serum ACTH and GH concentrations were similar to those of hypothalamic NE and 5-HT activities. Multiple regression analyses with stepwise procedure revealed that hypothalamic NE and 5-HT activities were respectively significant determinants of serum ACTH and GH concentrations. Apart from the direct influence of neostigmine on ACTH and GH secretions, it is suggested that the changes in hypothalamic monoaminergic activities play an important role in modulating ACTH and GH secretions following the administration of neostigmine.
Gotoh
M
M
Department of Laboratory Medicine, Aichi Medical University, Japan.
Hirooka
Y
Y
Tajima
T
T
Iguchi
A
A
Smythe
G A
GA
D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000818:Animals; D015306:Biogenic Monoamines / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D013006:Growth Hormone / Q000378:metabolism*; D007031:Hypothalamus / Q000166:cytology / Q000502:physiology*; D007276:Injections, Intraventricular; D008297:Male; D009388:Neostigmine / Q000008:administration & dosage* / Q000494:pharmacology; D009474:Neurons / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar
D015306:Biogenic Monoamines; D009388:Neostigmine; D000324:Adrenocorticotropic Hormone; D013006:Growth Hormone