Neonatal raphe lesions increase dopamine fibers in prefrontal cortex of adult rats.
In order to characterize how the dopamine (DA) and serotonin (5HT) systems may be interacting in medial prefrontal cortex (mPFC) during postnatal development, the specific toxin 5,7-dihydroxytryptamine (5,7-DHT) was used to induce lesions of the nucleus raphe dorsalis (NRD) in neonatal rats and the density of tyrosine hydroxylase-immunoreactive varicosities (TH-IRv) was assessed. During the early adult period, lesioned rats showed a significant increase in the density of the TH-IR fibers in layers V and VI when compared with sham-treated animals. These results suggest that postnatal development in medial prefrontal cortex may be associated with a competitive interaction between cortical monoaminergic systems, such that an early disturbance in the development of the 5HT innervation can potentially induce a hyperinnervation of DA fibres.
Bolte Taylor
J
J
Laboratory for Structural Neuroscience, McLean Hospital, Belmont, MA 02178, USA.
Cunningham
M C
MC
Benes
F M
FM
D000818:Animals; D004298:Dopamine / Q000502:physiology*; D007150:Immunohistochemistry; D008297:Male; D009412:Nerve Fibers / Q000502:physiology*; D017397:Prefrontal Cortex / Q000502:physiology*; D011903:Raphe Nuclei / Q000502:physiology*; D051381:Rats; D012701:Serotonin / Q000502:physiology*; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis; D017557:Ventral Tegmental Area / Q000502:physiology; D014741:Video Recording; D014886:Weaning
D012701:Serotonin; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine