Objective—To determine the effects of continuous
low-dose infusion of lipopolysaccharide (LPS) on the
expression of E-selectin and intercellular adhesion
molecule-1 (ICAM-1) mRNA and neutrophil accumulation
in the lungs, liver, spleen, small intestine, and
pancreas in dogs.
Animals—11 healthy adult Beagles.
Procedure—Dogs received a continuous infusion of a
low dose (10 µg/kg/h, IV) of LPS ( Escherichia coli055:B5)
or saline (0.9% NaCl) solution (20 mL/kg/h, IV) for 8
hours. Activity levels of tumor necrosis factor-α (TNF-α),
interleukin-1β (IL-1β), and interleukin-6 (IL-6) and the number
of WBCs in circulation were examined before and 1,
2, 4, and 8 hours after the onset of LPS infusion.
Expression of E-selectin and ICAM-1 mRNA and the
number of neutrophils in each tissue were examined.
Results—After the onset of LPS infusion, serum
TNF-α and IL-1β activities transiently increased.
Thereafter, IL-6 activity increased, and high IL-6 activity
was maintained throughout the experiment. In
dogs in the LPS group, expression of E-selectin
mRNA increased only in the lungs, and expression of
ICAM-1 mRNA increased in the lungs and liver; the
number of neutrophils in the tissue increased in the
lungs and liver.
Conclusions and Clinical Relevance—Results suggested
that expression of E-selectin and ICAM-1
mRNA increased during sepsis, particularly in the
lungs and liver, and that this increase was associated
with neutrophil accumulation. Hence, inhibiting the
activation of endothelial cells in the lung and liver may
decrease organ damage caused by accumulated neutrophils
and help regulate multiple-organ dysfunction.
(Am J Vet Res 2005;66:1259–1266)
OBJECTIVE To histologically evaluate and compare features of myofibers within the elongated soft palate (ESP) of brachycephalic and mesocephalic dogs with those in the soft palate of healthy dogs and to assess whether denervation or muscular dystrophy is associated with soft palate elongation.
SAMPLE Soft palate specimens from 24 dogs with ESPs (obtained during surgical intervention) and from 14 healthy Beagles (control group).
PROCEDURES All the soft palate specimens underwent histologic examination to assess myofiber atrophy, hypertrophy, hyalinization, and regeneration. The degrees of atrophy and hypertrophy were quantified on the basis of the coefficient of variation and the number of myofibers with hyalinization and regeneration. The specimens also underwent immunohistochemical analysis with anti-neurofilament or anti-dystrophin antibody to confirm the distribution of peripheral nerve branches innervating the palatine myofibers and myofiber dystrophin expression, respectively.
RESULTS Myofiber atrophy, hypertrophy, hyalinization, and regeneration were identified in almost all the ESP specimens. Degrees of atrophy and hypertrophy were significantly greater in the ESP specimens, compared with the control specimens. There were fewer palatine peripheral nerve branches in the ESP specimens than in the control specimens. Almost all the myofibers in the ESP and control specimens were dystrophin positive.
CONCLUSIONS AND CLINICAL RELEVANCE These results suggested that palatine myopathy in dogs may be caused, at least in part, by denervation of the palatine muscles and not by Duchenne- or Becker-type muscular dystrophy. These soft palate changes may contribute to upper airway collapse and the progression of brachycephalic airway obstructive syndrome.
Objective—To determine whether small intestinal
ischemia and reperfusion affects intestinal intramucosal
pH (pHi), arterial and portal venous blood gas
values, and intestinal blood flow (IBF) and to investigate
relationships between regional intestinal tissue
oxygenation and systemic variables in dogs.
Animals—15 healthy adult Beagles.
Procedure—Occlusion of superior mesenteric artery
(SMA) for 0, 30, or 60 minutes, followed by reperfusion
for 180 minutes, was performed; IBF, pHi, arterial and
portal venous blood gas values, arterial pressure, and
heart rate were measured at various time points; and
intestinal mucosal injury was histologically graded.
Results—Occlusion of the SMA induced significant
decreases in pHi and IBF. After the release of the
occlusion, IBF returned rapidly to baseline values, but
improvement in pHi was slow. Arterial and portal
venous blood gas analyses were less sensitive than
tonometric measurements of pHi, and there was no
correlation between results of blood gas analyses and
tonometric measurements. Histologic score for intestinal
mucosal injury increased significantly, depending
on duration of ischemia, and there was a correlation
between tonometric results and the histologic score.
Conclusion and Clinical Relevance—Results suggest
that it is difficult to accurately evaluate local oxygenation
disorders by monitoring at the systemic
level, whereas clinically pHi is the only reliable indicator
of inadequate regional intestinal tissue oxygenation
in dogs. (Am J Vet Res 2002;63:804–810)