Paradoxical actions of the NO donor SIN-I on single laryngeal motoneurons in the nucleus ambiguus.
In order to study the pharmacological action of the NO donor SIN-1 upon laryngeal motoneurons, we focally iontophoresed SIN-1 onto single motoneurons identified by antidromic stimulation of the recurrent nerve. SIN-1 produced opposing effects on motoneuron activities. Of 34 identified motoneurons, 38.2% showed a statistically significant decrease (decreasing group), while 29.4% showed an increase in their antidromic response to SIN-1 application (increasing group), respectively. The remaining neurons did not show any change (no change group). When the antidromic spike amplitude during the precontrol period was compared between the three groups, both the increasing and decreasing groups exhibited larger antidromic spikes than those measured in the no change group. The results are discussed in terms of dual pharmacological actions of NO.
Yajima
Y
Y
Department of Physiology, Hyogo College of Medicine, Nishinomiya Hyogo, Japan.
Hayashi
Y
Y
Hayakawa
T
T
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D004305:Dose-Response Relationship, Drug; D007823:Laryngeal Nerves / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D008297:Male; D008526:Medulla Oblongata / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D008981:Molsidomine / Q000031:analogs & derivatives* / Q000494:pharmacology; D009046:Motor Neurons / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D020030:Nitric Oxide Donors; D009569:Nitric Oxide; C002385:linsidomine; D008981:Molsidomine