Substance P-immunoreactive innervation from the retina to the suprachiasmatic nucleus in the rat.
The present study examined substance P (SP) innervation in the suprachiasmatic nucleus (SCN) of the rat. In the colchicine-untreated rat, SP-immunoreactive fibers formed a dense oval plexus in the ventral part of the SCN. After bilateral eye enucleation, there was a marked reduction in SP-immunoreactive fibers in the ventral part of the SCNs. The SP-immunoreactive neurons in the retinal ganglion cell layer were retrogradely labeled after injection of Fluoro-gold into the SCN. These findings indicate the presence of the SP innervation from the retina to the SCN in the rat. The role of SP in the retino-hypothalamic tract was discussed from the light-dark cycle.
Takatsuji
K
K
Osaka Prefectural College of Nursing, Japan.
Miguel-Hidalgo
J J
JJ
Tohyama
M
M
D000818:Animals; D001370:Axonal Transport; D015353:Eye Enucleation; D005456:Fluorescent Dyes; D006735:Horseradish Peroxidase; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D009412:Nerve Fibers / Q000502:physiology / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains; D012160:Retina / Q000033:anatomy & histology / Q000166:cytology / Q000502:physiology*; D012165:Retinal Ganglion Cells / Q000166:cytology / Q000502:physiology*; D013266:Stilbamidines; D013373:Substance P / Q000032:analysis*; D013493:Suprachiasmatic Nucleus / Q000033:anatomy & histology / Q000166:cytology / Q000502:physiology*; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; D014909:Wheat Germ Agglutinins
C049774:2-hydroxy-4,4'-diamidinostilbene, methanesulfonate salt; D005456:Fluorescent Dyes; D013266:Stilbamidines; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; D014909:Wheat Germ Agglutinins; D013373:Substance P; D006735:Horseradish Peroxidase