Distribution and synaptology of dopaminergic fibers in the mature and developing lateral septum of the rat.
The dopamine innervation of the adult and developing lateral septum of the rat was investigated with light and electron microscope immunocytochemistry using anti-dopamine antibodies. Light microscopic analysis showed that the pattern of innervation of the lateral septum exhibited a marked reorganization during the first 2 postnatal weeks, when it acquired features comparable to the adult. Ultrastructural analysis suggested that there may be two different dopamine inputs in the lateral septum. The first develops earlier in life and, through symmetrical axodendritic synapses, affects remote parts of neurons and may cause inhibition. The second develops later and, through asymmetrical axosomatic synapses, affects neuronal somata and may cause excitation. These findings may explain the reported contradictory results concerning the physiological role of dopamine in neurons of the lateral septum.
Antonopoulos
J
J
Department of Anatomy, School of Veterinary Medicine, University of Thessaloniki, Greece. jant@vet.auth.gr
Dinopoulos
A
A
Dori
I
I
Parnavelas
J G
JG
D000818:Animals; D000831:Animals, Newborn; D004298:Dopamine / Q000502:physiology*; D016253:Microscopy, Immunoelectron; D009412:Nerve Fibers / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D012688:Septum Pellucidum / Q000166:cytology / Q000254:growth & development* / Q000648:ultrastructure; D013569:Synapses / Q000502:physiology*
D004298:Dopamine