Projections from and to the superior colliculus in the nucleus of the optic tract combined with postembedding GABA immunocytochemistry in the rabbit.
The reciprocal connection between the nucleus of the optic tract and the superior colliculus has been described for several species. In both nuclei GABA is an important transmitter and recently it has been shown that GABA plays a significant role in this connection. To investigate this reciprocal connection at the ultrastructural level in the rabbit, anterograde and retrograde tracers were injected in the superior colliculus. Ultrathin sections were incubated with anti-GABA to elucidate the presence of GABA in retrogradely labeled neurons or anterogradely labeled terminals in the nucleus of the optic tract. The present results show that GABA is present in several neurons projecting from the nucleus of the optic tract to the superior colliculus and that all neurons involved in this projections are contacted by GABA immunopositive terminals. In the projection from the superior colliculus to the nucleus of the optic tract GABA play a less significant role.
Nunes Cardozo
B
B
Department of Morphology, The Netherlands Ophthalmic Research Institute, Amsterdam.
Wortel
J
J
D000344:Afferent Pathways / Q000648:ultrastructure; D000818:Animals; D002772:Cholera Toxin; D004525:Efferent Pathways / Q000648:ultrastructure; D005829:Geniculate Bodies / Q000033:anatomy & histology*; D017979:Gold Colloid; D011817:Rabbits; D012160:Retina / Q000033:anatomy & histology; D013477:Superior Colliculi / Q000033:anatomy & histology*; D014795:Visual Pathways / Q000648:ultrastructure*; D005680:gamma-Aminobutyric Acid / Q000032:analysis*
D017979:Gold Colloid; D005680:gamma-Aminobutyric Acid; D002772:Cholera Toxin