[Gaba innervation of serotonergic neurones innervating the thoracic marrow of the rat. Immunocytochemical and autoradiographic combination after retrograde axonal transport with tritiated serotonin ].
Anatomical relationship between GABA terminals and serotonergic neurons that innervate the thoracic spinal cord was studied using combined methods: autoradiography following (3H) 5-HT retrograde transport and immunocytochemistry for GABA. Following (3H) 5-HT injections into the thoracic spinal cord, serotonergic neurons of raphe pallidus and magnus were specifically radiolabelled. At optic and electron microscopic levels, radiolabelled cells of raphe magnus and pallidus were in contact with GABA immunoreactive pre-synaptic nerve terminals. Some radiolabelled cell bodies were contacted by both GABA immunoreactive and immunonegative terminals. These results indicate the existence of a direct GABAergic input onto the medullary serotonergic neurons projecting to the thoracic spinal cord and suggest both GABAergic and non-GABAergic regulation of these serotonergic neurons. Thus, combination of both a specific tracing technique and immunocytochemistry offers considerable advantages of specificity and sensibility for the study of interrelationship between chemically defined neuronal pathways and/or of transmitter co-existence.
Araneda
S
S
Département de Cytologie, URA CNRS 1199, Université Pierre et Marie Curie, Paris, France.
Magoul
R
R
Calas
A
A
D000818:Animals; D001345:Autoradiography / Q000379:methods; D001369:Axons; D007150:Immunohistochemistry; D007395:Interneurons / Q000737:chemistry / Q000648:ultrastructure*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000032:analysis*; D013116:Spinal Cord / Q000737:chemistry / Q000648:ultrastructure*; D005680:gamma-Aminobutyric Acid / Q000032:analysis*
D012701:Serotonin; D005680:gamma-Aminobutyric Acid
Mise en évidence d'une innervation gabaergique de neurones serotonergiques innervant la moëlle thoracique du rat. Couplage de l'immunocytochimie et de l'autoradiographie après transport axonal rétrograde lié à la sérotonine tritiée.