The effect of electrical muscle stimulation on the prevention of disuse muscle atrophy in patients with consciousness disturbance in the intensive care unit.

PURPOSE: Disuse atrophy of the lower limbs of patients with consciousness disturbance has often been recognized as "an unavoidable consequence," such that the mechanism was not investigated diligently. In this study, we examined the preventive effects of electrical muscle stimulation (EMS) against disuse atrophy of the lower limbs in patients in coma after stroke or traumatic brain injury in the intensive care unit. MATERIALS AND METHODS: We evaluated changes in cross-sectional area of lower limb muscles weekly with computed tomography in 6 control group patients and 9 EMS group patients. Electrical muscle stimulation was performed daily from day 7 after admission. We evaluated the anterior thigh muscle compartment, posterior thigh muscle compartment, anterior leg muscle compartment, and posterior leg muscle compartment. RESULTS: In the control group, the decrease in cross-sectional area progressed in all compartments every week (P < .0001). Cross-sectional areas of all compartments at day 14 were significantly decreased in the control group compared with those in the EMS group at day 7 (P < .001). We were able to limit the rate of muscle atrophy as measured in the cross-sectional areas to within 4% during the period of EMS (days 7-42) in 5 patients. The difference between the control and the EMS groups was statistically significant (P < .001). CONCLUSION: Electrical muscle stimulation is effective in the prevention of disuse muscle atrophy in patients with consciousness disorder.

Cerebrospinal fluid concentrations of anti-inflammatory mediators in early-phase severe traumatic brain injury.

In our previous study of patients with early-phase severe traumatic brain injury (TBI), the anti-inflammatory interleukin (IL)-10 concentration was lower in cerebrospinal fluid (CSF) than in serum, whereas proinflammatory IL-1beta and tumor necrosis factor (TNF)-alpha concentrations were higher in CSF than in serum. To clarify the influence of additional injury on this disproportion between proinflammatory and anti-inflammatory mediators, we compared their CSF and serum concentrations in patients with severe TBI with and without additional injury. All 35 study patients (18 with and 17 without additional injury) had a Glasgow Coma Scale score of 8 or less upon admission. With the exception of additional injury, clinical characteristics did not differ significantly between groups. CSF and serum concentrations of two proinflammatory mediators (IL-1beta and TNF-alpha,) and three anti-inflammatory mediators (IL-1 receptor antagonist [IL-1ra], soluble TNF receptor-I [sTNFr-I], and IL-10) were measured and compared at 6 h after injury. CSF concentrations of proinflammatory mediators were much higher than the corresponding serum concentrations in both patient groups (P < 0.001). In contrast, serum concentrations of anti-inflammatory mediators were much higher than the paired CSF concentrations in patients with additional injury (P < 0.001), but serum concentrations were lower than or equal to the corresponding CSF concentrations in patients without additional injury. CSF concentrations of IL-1beta, IL-1ra, sTNFr-I, and IL-10 were significantly higher (P < 0.01 for all) in patients with high intracranial pressure (ICP; n = 11) than in patients with low ICP (n = 24), and were also significantly higher (P < 0.05 for all) in patients with an unfavorable outcome (n = 14) than in patients with a favorable outcome (n = 21). These findings indicate that increased serum concentrations of anti-inflammatory mediators after severe TBI are mainly due to additional extracranial injury. We conclude that anti-inflammatory mediators in CSF may be useful indicators of the severity of brain damage in terms of ICP as well as overall prognosis of patients with severe TBI.

Specific localization of an inwardly rectifying K(+) channel, Kir4.1, at the apical membrane of rat gastric parietal cells; its possible involvement in K(+) recycling for the H(+)-K(+)-pump.

Hydrochloric acid (HCl) is produced in parietal cells of gastric epithelium by a H(+)-K(+) pump. Protons are secreted into the gastric lumen in exchange for K(+) by the action of the H(+)-K(+)-ATPase. Luminal K(+) is essential for the operation of the pump and is thought to be supplied by unidentified K(+) channels localized at the apical membrane of parietal cells. In this study, we showed that histamine- and carbachol-induced acid secretion from isolated parietal cells monitored by intracellular accumulation of aminopyrine was depressed by Ba(2+), an inhibitor of inwardly rectifying K(+) channels. Among members of the inwardly rectifying K(+) channel family, we found with reverse transcriptase-polymerase chain reaction analyses that Kir4.1, Kir4.2 and Kir7.1 were expressed in rat gastric mucosa. With immunohistochemical analyses, Kir4.1 was found to be expressed in gastric parietal cells and localized specifically at their apical membrane. The current flowing through Kir4.1 channel expressed in HEK293T cells was not affected by reduction of extracellular pH from 7.4 to 3. These results suggest that Kir4.1 may be involved in the K(+) recycling pathway in the apical membrane which is required for activation of the H(+)-K(+) pump in gastric parietal cells.