Neuropeptide Y, enkephalin and noradrenaline coexist in sympathetic neurons innervating the bovine spleen. Biochemical and immunohistochemical evidence.
The subcellular distribution of noradrenaline (NA), neuropeptide Y (NPY), Met- and Leu-enkephalin (ENK), substance P (SP), somatostatin (SOM), and vasoactive intestinal polypeptide (VIP) was investigated in homogenates of bovine splenic nerve. The distribution of noradrenergic peptide-containing nerves in the bovine celiac ganglion, splenic nerve and terminal areas in spleen was studied by indirect immunofluorescence histochemistry using antisera to tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (DBH), NPY, enkephalin peptides, SP, SOM, VIP, and peptide HI (PHI). After density gradient centrifugation, high levels of NPY- and ENK-like immunoreactivity (LI) were found in high-density gradient fractions, coinciding with the main NA peak. SP, SOM and VIP were found in fractions with a lower density, VIP being also enriched in a heavy fraction; the latter three peptides were present in low concentrations. Immunohistochemistry revealed that staining for NPY-LI and ENK-LI partly overlapped that for TH and DBH in celiac ganglia, splenic nerve axons and terminal areas of spleen. Almost all principal ganglion cells were TH- and DBH-immunoreactive. Many were also NPY-immunoreactive, whereas a smaller number were ENK-positive. In the celiac ganglion patches of dense SP-positive networks and some VIP/PHI- and ENK-immunoreactive fibers were seen around cell bodies. The results indicate that NPY and ENK are stored with NA in large dense-cored vesicles in unmyelinated axons of bovine splenic nerve. SP, SOM and VIP appear in different organelles in axon populations separate from sympathetic noradrenergic nerves.
Fried
G
G
Terenius
L
L
Brodin
E
E
Efendic
S
S
Dockray
G
G
Fahrenkrug
J
J
Goldstein
M
M
Hökfelt
T
T
D000320:Adrenergic Fibers / Q000032:analysis*; D000818:Animals; D002417:Cattle; D002458:Cell Fractionation; D002499:Centrifugation, Density Gradient; D004745:Enkephalins / Q000032:analysis; D005455:Fluorescent Antibody Technique; D005728:Ganglia, Sympathetic / Q000032:analysis; D009419:Nerve Tissue Proteins / Q000032:analysis*; D009478:Neuropeptide Y; D009638:Norepinephrine / Q000032:analysis; D013004:Somatostatin / Q000032:analysis; D013154:Spleen / Q000294:innervation*; D013194:Staining and Labeling; D013373:Substance P / Q000032:analysis; D014660:Vasoactive Intestinal Peptide / Q000032:analysis
D004745:Enkephalins; D009419:Nerve Tissue Proteins; D009478:Neuropeptide Y; D013373:Substance P; D014660:Vasoactive Intestinal Peptide; D013004:Somatostatin; D009638:Norepinephrine