[NO-ergic rat brain commissural neurons in the norm and during opiate administration].
Using histochemical reaction demonstrating NADPH-diaphorase (NADPH-d), the dynamics of NO synthesis was studied in the rat brain raphe nuclei following intravenous injection of morphine hydrochloride. In normal conditions NADPH-d activity was demonstrated in neurons of all raphe nuclei. Acute and chronic administration of morphine in different doses (0.5 mg/kg and 5 mg/kg) was found to inhibit NO-ergic activity of the major part of raphe nuclei neurons. The depression of NADPH-d activity was unequal in different nuclei. The NO-ergic changes are caused by an activation of opiate receptors, as they depend on morphine dose, while the application of opiate antagonist naloxone restores the NO-ergic function of raphe neurons. Formation of tolerance to opiate analgetic effect is accompanied by a significant, though short-lasting increase of NO synthesis activity. It is suggested that the changes in NO-ergic function of raphe neurons may influence brain serotonin balance after opiate administration.
Diuĭzen
I V
IV
Department of Histology, and Faculty of Postgraduate Training Department of Narcology, Vladivostok State Medical University, Laboratory of Pharmacology, Institute of Marine Biology, RAS Far Eastern Branch, Vladivostok.
Deridovich
I I
II
Kurbatskiĭ
R A
RA
Shorin
V V
VV
D000818:Animals; D004305:Dose-Response Relationship, Drug; D008297:Male; D009020:Morphine / Q000008:administration & dosage / Q000494:pharmacology*; D009252:NADPH Dehydrogenase; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D011903:Raphe Nuclei / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D009569:Nitric Oxide; D009020:Morphine; D009252:NADPH Dehydrogenase