Microvascular system of the lumbar dorsal root ganglia in rats. Part II: neurogenic control of intraganglionic blood flow.
OBJECTIVE
The dorsal root ganglion (DRG) should not be overlooked when considering the mechanism of low-back pain and sciatica, so it is important to understand the morphological features of the vascular system supplying the DRG. However, the neurogenic control of intraganglionic blood flow has received little attention in the past. The authors used an immunohistochemical technique to investigate the presence and distribution of autonomic and sensory nerves in blood vessels of the DRG.


METHODS
Ten Wistar rats were used. To investigate the mechanism of vasomotion on the lumbar DRG, the authors used immunohistochemical methods. Sections were incubated overnight with antisera to tyrosine hydroxylase (TH), aromatic L-amino-acid decarboxylase (AADC), 5-hydroxytryptamine, substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal peptide (VIP), somatostatin (SOM), neuropeptide Y (NPY), leucine-enkephalin, and cholineacetyl transferase (Ch-E). The avidin-biotin complex method was used as the immunohistochemical procedure, and the sections were observed under a light microscope.


RESULTS
In the immunohistochemical study, TH-, AADC-, SP-, CGRP-, VIP-, SOM-, NPY-, and Ch-E-positive fibers were seen within the walls of blood vessels in the DRG. This study revealed the existence of a comprehensive perivascular adrenergic, cholinergic, and peptidergic innervation of intraganglionic blood vessels, with a possible role in neurogenic regulation (autoregulation) of intraganglionic circulation.


CONCLUSIONS
The presence of perivascular nerve plexuses around intraganglionic microvessels suggests that autonomic nerves play an important role in intraganglionic circulation.
Kobayashi
Shigeru
S
Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences, The University of Fukui, Matsuoka, FukuiJapan.
Mwaka
Erisa Sabakaki
ES
Baba
Hisatoshi
H
Kokubo
Yasuo
Y
Yayama
Takafumi
T
Kubota
Masafumi
M
Nakajima
Hideaki
H
Meir
Adam
A
D000818:Animals; D001369:Axons / Q000502:physiology; D005727:Ganglia, Spinal / Q000098:blood supply* / Q000502:physiology; D007150:Immunohistochemistry; D008159:Lumbar Vertebrae; D008833:Microcirculation; D055806:Microvessels / Q000294:innervation* / Q000502:physiology*; D009046:Motor Neurons / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011984:Sensory Receptor Cells / Q000502:physiology
D018377:Neurotransmitter Agents