TY - JOUR
T1 - Upregulation of intracellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 after unilateral nerve injury in the peripheral taste system
AU - Cavallin, Melissa Ann
AU - McCluskey, Lynnette Phillips
PY - 2007/2/1
Y1 - 2007/2/1
N2 - In the peripheral taste system, activated macrophages are recruited to both sides of the tongue after unilateral sectioning of the chorda tympani nerve (CT). Neural degeneration elicits macrophage entry in other systems by upregulating vascular adhesion molecules. We hypothesized that CT sectioning leads to a bilateral increase in intracellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 expression on lingual vessels. To test this hypothesis, rats were euthanized at time points from 6 hr to 7 days post-sectioning. Frozen sections of tongue were processed for immunohistochemical staining for ICAM-1 and VCAM-1. Tongue homogenates from additional rats were analyzed with ELISA. ICAM-1 expression increases first on the denervated side of the tongue at 24 hr post-section and then on the uninjured side at 48 hr post-section. ICAM-1 remains elevated through Day 7 post-sectioning on both sides of the tongue. Dietary sodium restriction, which prevents the macrophage response to nerve sectioning, had no effect on ICAM-1 levels. VCAM-1+ vessels are increased on the denervated side of the tongue at 24-48 hr post-section in control-fed rats. However, dietary sodium restriction prevents the increase. These results indicate that vascular adhesion molecules are differentially regulated by CT sectioning. We suggest that macrophage entry, migration, and modulation of taste function are downstream of dynamic expression of adhesion molecules.
AB - In the peripheral taste system, activated macrophages are recruited to both sides of the tongue after unilateral sectioning of the chorda tympani nerve (CT). Neural degeneration elicits macrophage entry in other systems by upregulating vascular adhesion molecules. We hypothesized that CT sectioning leads to a bilateral increase in intracellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 expression on lingual vessels. To test this hypothesis, rats were euthanized at time points from 6 hr to 7 days post-sectioning. Frozen sections of tongue were processed for immunohistochemical staining for ICAM-1 and VCAM-1. Tongue homogenates from additional rats were analyzed with ELISA. ICAM-1 expression increases first on the denervated side of the tongue at 24 hr post-section and then on the uninjured side at 48 hr post-section. ICAM-1 remains elevated through Day 7 post-sectioning on both sides of the tongue. Dietary sodium restriction, which prevents the macrophage response to nerve sectioning, had no effect on ICAM-1 levels. VCAM-1+ vessels are increased on the denervated side of the tongue at 24-48 hr post-section in control-fed rats. However, dietary sodium restriction prevents the increase. These results indicate that vascular adhesion molecules are differentially regulated by CT sectioning. We suggest that macrophage entry, migration, and modulation of taste function are downstream of dynamic expression of adhesion molecules.
KW - Chorda tympani nerve
KW - Dietary sodium restriction
KW - Macrophage recruitment
KW - Neural degeneration
KW - Neuroimmune interactions
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U2 - 10.1002/jnr.21128
DO - 10.1002/jnr.21128
M3 - Article
C2 - 17131425
AN - SCOPUS:33846865556
SN - 0360-4012
VL - 85
SP - 364
EP - 372
JO - Journal of Neuroscience Research
JF - Journal of Neuroscience Research
IS - 2
ER -