Work

GABA-mediated inhibition of locus coeruleus from the dorsomedial rostral medulla

Year: 1989
Type: article
Abstract: Recent anatomic studies in our laboratory (Aston-Jones et al., 1986) identified the nucleus prepositus hypoglossi (PrH) in the dorsomedial medulla as a major afferent of the locus coeruleus (LC). In the present studies, the influence of projections from PrH to LC was assessed in anesthetized rats. Focal electrical stimulation of PrH inhibited the spontaneous discharge of 42 of 47 LC neurons; the latency to onset of such inhibition was 19.8 +/- 2.5 msec and its duration was 172.4 +/- 10.4 msec. PrH-evoked inhibition of LC neurons was unaffected by administration of the opiate receptor antagonist naloxone or the alpha 2-receptor antagonist idazoxan but was substantially reduced by systemic picrotoxin, an antagonist of GABA. The GABAA receptor antagonist bicuculline methiodide blocked the inhibition from PrH, whether applied by local microinfusion or iontophoresis into the LC. These results lead us to propose that PrH provides a direct inhibitory synaptic input to LC, for which GABA is the likely transmitter.
Institution: New York University
Language: English
Open Access status: hybrid
OpenAlex ID: W1566547168
FWCI: 2.656
Cites: 24
Cited by: 179
Related to: 10