[Modulation of periaqueductal gray neuronal activity by influences of brain stem monoaminergic structures].
Studies of spontaneous firing (SF) in the midbrain periaqueductal gray (PAG) neurons before and after stimulation of nucleus raphe magnus, locus coeruleus and substantia nigra were performed on the rat anesthetized with Hexenal (200 mg/kg). Three types of neurons different in SF structure were found. Stimulation of indicated structures increased SF rate in 11-14.5% and decreased 31-47% of the studied neurons of the third group. Simultaneous stimulation of two structures did not induce a remarkable increase of SF rate. If one of two simultaneously stimulated structures suppressed SF the ultimate effect was, as a rule, depression of SF. Greatest suppression of SF was observed if stimulation of nucleus raphe magnus was induced. Role of PAG in organization of the brain stem component of antinociceptive mechanism is discussed.
Piliavskiĭ
A I
AI
Iakhnitsa
V A
VA
Bulgakova
N V
NV
Limanskiĭ
Iu P
IuP
D000818:Animals; D015306:Biogenic Monoamines / Q000502:physiology*; D001933:Brain Stem / Q000502:physiology*; D004558:Electric Stimulation; D008564:Membrane Potentials / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D010487:Periaqueductal Gray / Q000166:cytology / Q000502:physiology*; D051381:Rats
D015306:Biogenic Monoamines
Moduliatsiia aktivnosti neĭronov tsentral'nogo cerogo veshchestva srednego mozga vliianiiami monoaminergicheskikh struktur stvola.