Are locus coeruleus neurons involved in blinking?
To investigate the involvement of the noradrenergic locus coeruleus (LC) in the reflex blink circuit, c-Fos and neuronal tracer experiments were performed in the rat. LC neurons involved in reflex blink were localized by analyzing c-Fos protein expression after electrical stimulation of the supraorbital nerve. Subsequently, neuronal tracers were injected in two different nuclei which are part of the reflex blink circuit. Anterograde tracer experiments in the sensory trigeminal complex (STC) explored the trigemino-coerulear connection; retrograde tracer experiments in the latero-caudal portion of the superior colliculus (SC) established coerulear-collicular connections. The combination of retrograde tracer injections into the latero-caudal SC portion combined with electrical stimulation of the supraorbital nerve identified c-Fos positive LC neurons that project to the latero-caudal SC. Our results revealed the existence of a STC-LC-SC loop.
Dauvergne
Céline
C
Laboratoire de Physiologie de la Manducation, UP7, 4 place Jussieu, 75252 Paris Cedex 05, France.
Smit
Albertine Ellen
AE
Valla
Jocelyne
J
Diagne
Monique
M
Buisseret-Delmas
Catherine
C
Buisseret
Pierre
P
Pinganaud
Gabrielle
G
Vanderwerf
Frans
F
D000344:Afferent Pathways / Q000166:cytology* / Q000502:physiology; D000818:Animals; D001767:Blinking / Q000502:physiology*; D005143:Eyelids / Q000294:innervation*; D007150:Immunohistochemistry; D008125:Locus Coeruleus / Q000166:cytology* / Q000502:physiology; D009474:Neurons / Q000166:cytology* / Q000502:physiology; D051381:Rats