There are few catecholamine- or neuropeptide Y-containing synapses in the intermediolateral cell column of rat thoracic spinal cord.
1. A quantitative electron microscopic immunocytochemical technique was used to assess the number of synapses immunoreactive for tyrosine hydroxylase (TH), phenylethanolamine N-methyl-transferase (PNMT) and neuropeptide Y (NPY) in the intermediolateral cell column in segments T2 and T3 of rat thoracic spinal cord. 2. TH synapses comprised about 5%; PNMT synapses 1-2%; and NPY synapses 1-2% of the total number of synapses in the intermediolateral cell column. All three types of synapses were predominantly or exclusively on dendrites. 3. Our results suggest that catecholamine/NPY neurons may not provide a major synaptic input to sympathetic preganglionic neurons in rat upper thoracic spinal cord.
Llewellyn-Smith
I J
IJ
Centre for Neuroscience, School of Medicine, Flinders University, Bedford Park, Australia.
Minson
J B
JB
Pilowsky
P M
PM
Chalmers
J P
JP
D000818:Animals; D007150:Immunohistochemistry; D008297:Male; D009478:Neuropeptide Y / Q000032:analysis*; D010625:Phenylethanolamine N-Methyltransferase / Q000032:analysis*; D051381:Rats; D011921:Rats, Inbred WKY; D013116:Spinal Cord / Q000737:chemistry / Q000648:ultrastructure*; D013569:Synapses / Q000737:chemistry*; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis*
D009478:Neuropeptide Y; D014446:Tyrosine 3-Monooxygenase; D010625:Phenylethanolamine N-Methyltransferase