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Electrical stimulation of wrist and fingers for hemiplegic patients.

Passive cyclical electrical stimulation was applied during a four-week treatment program to the wrist and finger extensors of 16 hemiplegic patients with flexor spasticity. The study noted the effects of this treatment on the patients' sensation; spasticity; passive range of motion of the wrist, metacarpophalangeal, and proximal interphalangeal joints; and strength in the wrist extensor muscles. Patients were divided into chronic and subacute groups. Both groups received electrical stimulation for three half-hour periods a day, seven days a week, as a substitute for all other range-of-motion techniques. Flexion contractures were prevented in the subacute group of patients at the wrist, metacarpophalangeal, and proximal interphalangeal joints. A statistically and clinically significant increase in wrist extension range occurred in the chronic group that had wrist flexion contractures before the electrical stimulation. Increased extension was noted at the metacarpophalangeal and proximal interphalangeal joints of patients in the chronic group. Those patients with some voluntary wrist extension before the treatment began were able to increase their extension strength during stimulation. No changes in skin sensation were noted and only a general trend in decreasing spasticity was apparent.

Adult↗

Prevention of quadriceps wasting after immobilization: an evaluation of the effect of electrical stimulation.

Eighteen male and 20 female patients who underwent reconstruction of their anterior cruciate ligament (ACL) with a flap from the patellar tendon were randomly assigned into either closed cast, isometric muscle training and electric stimulation (ES group), or closed cast and isometric training alone (control group). The degree of quadriceps wasting was determined from computerized tomographic scans (CT) before and 6 weeks after surgery. Electrical stimulation was given with a battery operated stimulator that produced a rectangular asymmetric balanced biphasic pulse shape. The pulse rate was 40 Hz and the pulse width 300 microseconds. Patients received 30 min of stimulation three times daily during 5.5 weeks. Female control patients showed a larger decrease in quadriceps area on CT than male control patients (P less than .001). No significant difference was found between male electrically stimulated patients and control patients. In female patients, there was on the contrary, a highly significant difference in favor of electrical stimulation (P less than .001) When the different parts of the quadriceps were studied, a significantly lower degree of atrophy of the vastus medialis was found after electrical stimulation. Vastus lateralis did not show any difference. Measurements of CT attenuation, pre- and post-operatively, showed a decrease in attenuation of 17% for the vastus medialis and lateralis of the operated leg after immobilization, indicating an increase in fat content. In the rectus femoris, however, there was an increase in attenuation of 14.6%. Percutaneous muscle biopsies from the vastus lateralis obtained before, one week after, and 6 weeks after surgery revealed that the cross-sectional area of the individual muscle fibers decreased less in the electrically stimulated than in controls, but the difference was not significant. There were no differences between the two groups in the activity of an oxidative enzyme, citrate synthase, or a glycolytic enzyme, phosphofructokinase (PFK). We conclude that females reacted more favorably than males to electrical stimulation of quadriceps during an immobilization period after knee surgery.

Adult↗

An artificial neural system for closed loop control of locomotion produced via neuromuscular electrical stimulation.

The use of neuromuscular electrical stimulation for restoration of gait in spinal cord injured subjects has been seriously pursued by many investigators for the past 15 years. By and large, however, systems to date require the intervention of a person, be it the patient or an observer, and are restricted to control of stimulation onset and termination. Further, existing systems are not adaptable to environmental and patient variations. This work proposes a system that relies on neural computing to determine proper muscle activation patterns from biomechanical signals. The intelligent system is trained to perform gait under supervision, after which it can be used to control muscle stimulation in an unknown environment. Computer simulations suggest that the best neural architecture for control of gait is a neural network including units corresponding to movement history. Separate networks for the stance and swing phases, respectively, were found to work better than a single neural network trained on the entire gait cycle. The artificial neural device proposed here also includes a voice recognition system that will allow for voluntary locomotion. A safety circuit has been designed to preclude acceptance of unwanted vocal commands in the latter system.

Computer Simulation↗

Electrical stimulation versus electromyographic biofeedback in the recovery of quadriceps femoris muscle function following anterior cruciate ligament surgery.

Both electrical stimulation and electromyographic biofeedback have been shown to be more effective than voluntary isometric exercise alone in the recovery of quadriceps femoris muscle force following anterior cruciate ligament (ACL) reconstruction. In a comparison of these two modalities, 30 patients with ACL reconstruction were randomly assigned to either a group receiving electrical stimulation in conjunction with voluntary isometric exercise or a group receiving biofeedback in conjunction with voluntary isometric exercise. Following 6 weeks of a rehabilitative exercise protocol, the quadriceps femoris muscle isometric peak torque in the operative limb was compared with that in the nonoperative limb. A t test of independent samples indicated that the biofeedback group recovered a significantly greater percentage of their nonoperative limb's peak torque than did the electrical stimulation group. Measurements of active knee extension were taken at weeks 1, 2, 4, and 6 of the exercise program. A two-way analysis of variance (groups x weeks) indicated no significant difference between the rate at which each group recovered full active extension. The authors concluded that biofeedback is more effective than electrical stimulation in facilitating the recovery of peak torque and that biofeedback is comparable to electrical stimulation in the recovery of active knee extension.

Adolescent↗

[Changes in the position of the ureterovesical junction during maximal voluntary contractions and during maximal vaginal electric stimulation of the pelvic floor muscles].

The objective of the study was to evaluate and compare the effect of the maximal voluntary muscle contraction of the pelvic floor (PFM) and contractions of the PFM evoked by maximal electric stimulation using an electrostimulation apparatus Conmax by monitoring the position of the urethrovesical junction by ultrasound. The trial comprised 20 women with confirmed stress incontinence of urine. With the patients in a supine position with abducted lower extremities an electrostimulation probe was inserted into the vagina. This was followed by perineal ultrasound (US) examination using an ACUSON 128 XP-10 apparatus and a convex tube 5 MHz. The ultrasound examination was made using the electrostimulation probe--at rest and during maximal voluntary contraction of the PFM. This was followed by maximal electric stimulation and after five minutes during stimulation the US examination was repeated. It was performed also during maximal electric stimulation (MES) concurrently with maximal voluntary contraction of the PFM. For electrostimulation a Conmax appartus was used. The applied frequency was 50 Hz, amplitude from 0 to 90 mA (grade 0-6), duration of pulse 0.75 ms. The maximum intensity of stimulation was determined by the patient, i.e. when stimulation was not yet painful. During US the authors investigated the gamma angle, i.e. the angle between the axis of the symphysis and the connecting line between the UV junction and the lower borderline of the symphysis. The mean difference of the gamma angle during voluntary contraction of the PFM and at rest was 13.6. During contraction caused by maximal electric stimulation of the PFM and at rest this difference was 21.3. The difference did not differ significantly during maximal electric stimulation of the PFM and during maximal electric stimulation and voluntary contraction of the PFM. From the trial ensues that contraction of the pelvic floor muscles during maximal electric stimulation is stronger as compared with the intensity of contraction caused by maximal voluntary contraction. The results confirm the favourable therapeutic effect of MES muscles of the pelvic floor in the treatment of urinary incontinence in women. These changes help to increase the muscular tonus and contractibility of pelvic floor muscles and thus promote also elevation of the neck of the urinary bladder. Elevation of the neck of the urinary bladder promotes normalization of intraabdominal transfer of pressure to the proximal urethra.

Electric Stimulation Therapy↗

Gastric electrical stimulation for medically refractory gastroparesis.

BACKGROUND & AIMS: This study investigated the efficacy of gastric electrical stimulation for the treatment of symptomatic gastroparesis unresponsive to standard medical therapy. METHODS: Thirty-three patients with chronic gastroparesis (17 diabetic and 16 idiopathic) received continuous high-frequency/low-energy gastric electrical stimulation via electrodes in the muscle wall of the antrum connected to a neurostimulator in an abdominal wall pocket. After implantation, patients were randomized in a double-blind crossover design to stimulation ON or OFF for 1-month periods. The blind was then broken, and all patients were programmed to stimulation ON and evaluated at 6 and 12 months. Outcome measures were vomiting frequency, preference for ON or OFF, upper gastrointestinal tract symptoms, quality of life, gastric emptying, and adverse events. RESULTS: In the double-blind portion of the study, self-reported vomiting frequency was significantly reduced in the ON vs. OFF period (P < 0.05) and this symptomatic improvement was consistent with the significant patient preference (P < 0.05) for the ON vs. OFF period determined before breaking the blind. In the unblinded portion of the study, vomiting frequency decreased significantly (P < 0.05) at 6 and 12 months. Scores for symptom severity and quality of life significantly improved (P < 0.05) at 6 and 12 months, whereas gastric emptying was only modestly accelerated. Five patients had their gastric electrical stimulation system explanted or revised because of infection or other complications. CONCLUSIONS: High-frequency/low-energy gastric electrical stimulation significantly decreased vomiting frequency and gastrointestinal symptoms and improved quality of life in patients with severe gastroparesis.

Adult↗

A reliable technique for the induction of locomotor-like activity in the in vitro neonatal rat spinal cord using brainstem electrical stimulation.

The use of brainstem electrical stimulation (BES) to evoke locomotion in in vivo preparations, such as the decerebrate cat, is well established. In contrast, despite the popularity of in vitro rodent spinal cord models, BES has not been adapted for routine induction of locomotion in these preparations. We describe a simple and reliable method of inducing locomotor-like activity in the in vitro neonatal rat spinal cord using BES. Relatively large amplitude (0.5-10mA), long duration (4-20ms) and low frequency (0.8-2.0Hz) pulses were delivered through a metal-in-glass electrode placed in contact with the ventral surface of the brainstem, without the need for precise targeting of specific sites. During continuous BES, locomotor-like activity (0.15-0.63Hz) persisted for over 45min. Episodes of locomotor-like activity could be recruited repeatedly for hours, using short periods (60s) of BES alternating with brief rest periods. Additional observations confirmed that the rhythmogenic effect of BES is mediated by excitation of spinal projections at the brainstem level, rather than spinal cord activation due to electrotonic spread of stimulus from the brainstem electrode. Endogenous activation of locomotor networks using BES offers important advantages over bath-applied application of neurochemicals to induce stepping in the in vitro rat model.

Animals↗

Changes in the perioral muscle responses to cortical TMS induced by decrease of sensory input and electrical stimulation to lower facial region.

OBJECTIVE: To determine the changes in the motor cortex due to repetitive electrical stimulation and cutaneous anesthesia in lower facial region. METHODS: A total of 11 subjects participated in the study of repetitive electrical stimulation, and 10 other subjects in the study of lower facial anesthesia. Facial nerve root and face associated cortical MEPs by transcranial magnetic stimulation (eight-shaped coil) were recorded from perioral muscles pre- and post- electrical stimulation and lower facial anesthesia. Cheek near to the corner of the mouth was transcutaneously stimulated by bipolar surface electrode giving repetitive electrical shocks at 5 Hz. Five percent lidocain/prilocain local anesthetic cream was applied to left or right lip-cheek region. RESULTS: There was no significant change in perioral MEP responses after 10-30 min of 5 Hz electrical stimulation. We found a significant increase of amplitude in cortical MEP recordings during lower facial anesthesia especially in cases of cortical magnetic stimulations ipsilateral and contralateral to the anaesthetized side and in perioral recordings contralateral to the anaesthetized side. CONCLUSIONS: The present study demonstrates that topical anesthesia to the lower facial region leads to cortical modulation and fast plastic changes in both hemispheres that are directed to the normal side.

Adult↗

Mechanism of antiarrhythmic efficacy of propafenone as assessed by programmed electrical stimulation in conscious dogs.

Programmed electrical stimulation (PES) was performed in 18 conscious, chronically instrumented mongrel dogs 6-21 days after a 4-h occlusion of the left anterior descending coronary artery (LAD). At baseline, 8 of 10 animals responded with sustained ventricular tachycardia (SVT) and 2 of 10 responded with ventricular fibrillation (VF). Cumulative administration of 2 and 4 mg/kg propafenone intravenously (i.v.) prevented induction of the baseline arrhythmia in 7 of 10 (p less than 0.05) and 5 of 10 (p = 0.1) animals, respectively. Cumulative administration of two doses of saline to 8 control animals with SVT inducible at baseline did not affect subsequent inducibility. QRS duration was only slightly prolonged after 2 mg/kg propafenone (+3.5 +/- 1.1 ms, p less than 0.05). Administration of 4 mg/kg was associated with a further increase in QRS duration (+8.0 +/- 2.3 ms, p less than 0.01) and a decrease in sinus cycle length (-60.0 +/- 17.2 ms, p less than 0.05). Propafenone consistently and significantly prolonged ventricular refractoriness only in responders. Furthermore, at both dosages, there was a negative correlation between drug-induced increases in ventricular refractoriness and baseline refractoriness (r = -0.72, p = 0.02; r = -0.81, p = 0.005 with 2 mg/kg and 4 mg/kg propafenone, respectively). Thus, the lesser antiarrhythmic efficacy of 4 mg/kg as compared with 2 mg/kg may result from excessive increases in intraventricular conduction time and/or unfavorable hemodynamic effects of this dose. Furthermore, our study confirms an association of the antiarrhythmic efficacy of propafenone with increases in ventricular refractoriness. In addition, the present investigation demonstrated that such increases in refractoriness are most likely to occur at short baseline values.

Animals↗

The use of therapeutic electrical stimulation in the treatment of hemiplegic cerebral palsy.

The effect of electrical stimulation of the anterior tibial muscles of children with hemiplegic cerebral palsy was studied. 10 children received electrical stimulation, applied by their parents daily for an hour for 35 days; they were compared with 10 matched controls. Active and passive ranges of movement of the ankle, and knee and ankle motion during walking were measured before and after therapy using electrogoniometers. The results showed a significant increase in passive range of movement among children receiving electrical stimulation. Gait analysis of knee and ankle motion showed little change.

Cerebral Palsy↗

Post-stimulus EMG complexes in the masseter muscle following gingival electrical stimulation in man.

Post-stimulus EMG complexes (PSECs) were elicited by means of electrical stimulation of the gingiva in six subjects during clenching in three biting positions, namely the maximal occlusion, the incisor edge-to-edge and the hyperpropulsive biting position. No interrelationship was found between the mechanically and electrically elicited PSECs. With electrical stimulation the PSEC morphology was not related to the biting position in contrast with the PSECs elicited with mechanical stimulation. Following gingival electrical stimulation, a P wave was not present in the PSEC.

Adolescent↗

Evidence that nitric oxide mediates non-adrenergic non-cholinergic relaxation induced by GABA and electrical stimulation in the rat isolated duodenum.

1. GABA (3 x 10(-4) M) and electrical stimulation (60 mV, 1 ms, 0.1 Hz) produced a non-adrenergic non-cholinergic (NANC) relaxation response in the rat isolated duodenum. 2. Tetrodotoxin (10(-6) M) incubation abolished GABA and electrical stimulation responses but not ATP (10(-3) M)-induced relaxation. 3. Desensitization to ATP (10(-3) M) or alpha, beta-methylene ATP (10(-5) M) and incubation with the P1 receptor antagonist 8-phenyltheophylline (10(-5) M) failed to affect relaxation induced by GABA and low frequency electrical stimulation. 4. The inhibitor of L-arginine-NO synthase N omega-Nitro-L-arginine methyl ester (L-NAME) (10(-4)-3 x 10(-4) M) reduced the NANC relaxations elicited by GABA and low frequency electrical stimulation in a dose-dependent manner. These effects were partially reversed by the addition of L-arginine (10(-3)-3 x 10(-3) M). ATP (10(-3) M)-induced relaxations were not modified by L-NAME (3 x 10(-4) M) incubation. 5. These results suggest that nitric oxide is involved in inhibitory NANC transmission in the rat duodenum. We provided original evidence that nitric oxide is involved in neurally mediated relaxations induced by GABA in rat isolated duodenum.

Adenosine Triphosphate↗

Vastus medialis electrical stimulation to improve lower extremity function following a lateral patellar retinacular release.

STUDY DESIGN: A single-case study design. OBJECTIVES: To examine the effect of electrical stimulation of the vastus medialis muscle on stiffness, pain and function for a patient with delayed functional progress following a lateral patellar retinacular release. BACKGROUND: Five months after an arthroscopic lateral patellar retinacular release, the patient, although highly motivated, had made little progress using routine exercises and taping. METHODS AND MEASURES: An electrical stimulation program producing approximately 300 contractions daily of the vastus medialis muscle was implemented. The electrical stimulation applied for 33 of the 36 days was a rectangular and balanced biphasic pulse of 625-micros duration, 70-Hz frequency, 8-second peak on-time, 3-second off-time, 1-second ramp-up, and 0.5-second ramp-down. Objective measures of stair climbing and hopping, together with the subjective measure of therapist-palpated superomedial patella displacement force, were recorded for each treatment visit. Other subjective measures were the patient's daily recordings of knee pain and stiffness. RESULTS: Patient-reported stiffness reduced rapidly as the actual and cumulative number of daily contractions of the vastus medialis muscle increased. After 8 days of electrical stimulation, the patient was able to ascend stairs unassisted and after another 21 days to hop unsupported. CONCLUSIONS: Stiffness rapidly reduced and function started to improve once the electrical stimulation program was implemented. Recovery during the 36 days of treatment with electrical stimulation was greater than during the previous 5 months using other methods. Compliance was not an issue, nor was muscle soreness.

Arthroscopy↗

Electrical stimulation of the midbrain increases heart rate and arterial blood pressure in awake humans.

Electrical stimulation of the hypothalamus, basal ganglia or pedunculopontine nucleus in decorticate animals results in locomotion and a cardiorespiratory response resembling that seen during exercise. This has led to the hypothesis that parallel activation of cardiorespiratory and locomotor systems from the midbrain could form part of the 'central command' mechanism of exercise. However, the degree to which subcortical structures play a role in cardiovascular activation in awake humans has not been established. We studied the effects on heart rate (HR) and mean arterial blood pressure (MAP) of electrically stimulating the thalamus and basal ganglia in awake humans undergoing neurosurgery for movement disorders (n = 13 Parkinson's disease, n = 1 myoclonic dystonia, n = 1 spasmodic torticollis). HR and MAP increased during high frequency (> 90 Hz) electrical stimulation of the thalamus (HR 5 +/- 3 beats min(-1), P = 0.002, MAP 4 +/- 3 mmHg, P = 0.05, n = 9), subthalamic nucleus (HR 5 +/- 3 beats min(-1), P = 0.002, MAP 5 +/- 3 mmHg, P = 0.006, n = 8) or substantia nigra (HR 6 +/- 3 beats min(-1), P = 0.001, MAP 5 +/- 2 mmHg, P = 0.005, n = 8). This was accompanied by the facilitation of movement, but without the movement itself. Stimulation of the internal globus pallidus did not increase cardiovascular variables but did facilitate movement. Low frequency (< 20 Hz) stimulation of any site did not affect cardiovascular variables or movement. Electrical stimulation of the midbrain in awake humans can cause a modest increase in cardiovascular variables that is not dependent on movement feedback from exercising muscles. The relationship between this type of response and that occurring during actual exercise is unclear, but it indicates that subcortical command could be involved in 'parallel activation' of the locomotor and cardiovascular systems and thus contribute to the neurocircuitry of 'central command'.

Adult↗

Reduction in excitability of the auditory nerve following electrical stimulation at high stimulus rates.

While recent studies have suggested that electrical stimulation of the auditory nerve at high stimulus rates (e.g., 1000 pulses/s) may lead to an improved detection of the fine temporal components in speech among cochlear implant patients, neurophysiological studies have indicated that such stimulation could place metabolic stress on the auditory nerve, which may lead to neural degeneration. To examine this issue we recorded the electrically evoked auditory brainstem response (EABR) of guinea pigs following acute bipolar intracochlear electrical stimulation using charge-balanced biphasic current pulses at stimulus rates varying from 100 to 1000 pulses/s and stimulus intensities ranging from 0.16 to 1.0 microC/phase. Charge density was held constant (approximately 75 microC cm-2 geom/phase) in those experiments. To monitor the recovery in excitability of the auditory nerve following this acute stimulation. EABR thresholds, wave I and III amplitudes and their latencies were determined for periods of up to 12 h following the acute stimulation. Higher stimulus rates and, to a lesser extent, higher intensities led to greater decrements in the post-stimulus EABR amplitude and prolonged the recovery period. While continuous stimulation at 100 pulses/s induced no decrement in the EABR, stimulation at 200 and 400 pulses/s produced an increasingly significant post-stimulus reduction of the EABR amplitude, which showed only partial recovery during the monitoring period. No EABR response could be evoked immediately following stimulation at 1000 pulses/s, using a probe intensity 16-19 dB below the stimulus intensity. However, partial EABR recovery was observed for wave III following stimulation at the lowest stimulus intensity (0.16 microC/phase). These stimulus-induced reductions in the EABR amplitude were also reflected in increased thresholds and latencies. Providing stimulus rate and intensity were held constant, stimulation at different charge densities (37.7, 75.5 and 150.7 microC cm-2 geom/phase) had no influence on the post-stimulus EABR recovery. Significantly, the introduction of a 50% duty cycle into the stimulus pulse train resulted in a more rapid and complete post-stimulus recovery of the EABR compared to continuous stimulation. These data suggest that stimulus rate is a major contributor to the observed reduction in excitability of the electrically stimulated auditory nerve. This reduction may be a result of an activity-induced depletion of neural energy resources required to maintain homeostasis. The present findings have implications for the design of safe speech-processing strategies for use in multichannel cochlear implants.

Animals↗

[An experimental study on the auditory brainstem response to electrical stimulation of the cochlea].

This animal research was undertaken to study some important issues for cochlear implantation. This included investigations of 1) the difference in the auditory brainstem responses (ABRs) to extra- and intracochlear electrical stimulations. 2) stimulus parameters and ABRs to a bipolar intracochlear stimulation, and 3) electrode placements and ABRs. There were no distinct differences in waveforms and input-output curves of ABRs between extracochlear electrical stimulation and intracochlear bipolar stimulation of the cochlea. Changes in amplitude and latency of ABRs were investigated at changes of the pulse amplitude or the pulse width of stimulating electric rectangular waves. Increase in the pulse amplitude or the pulse width resulted in increase of the amplitude of ABRs and no increase in the ABR latency. This results showed the amplitude of ABR was dependent on the amount of electricity; coulomb. Electrically evoked ABRs were studied for stimulations at different sites of the cochlea. The ABR elicited with a bipolar electrode placed at the third turn of the cochlea had a longer latency of each peak of ABR waves than the one at the basal turn. This indicates that electrical stimulation with a bipolar electrode can give rise to a localized excitation in the cochlea and a latency change along the longitudinal axis of the cochlea, so that it suggests a multichannel cochlea implant system can transmit more information as a spacious pattern than a single channel system.

Animals↗

Effects of electrical stimulation on GAP-43 expression in mouse sensory neurons.

Effects of electrical activity on GAP-43 expression were tested in mouse dorsal root ganglion (DRG) neurons subjected to electrical stimulation in culture. Patterned electrical stimulation was provided through extracellular electrodes placed in multicompartment cell culture chambers. Stimulation was delivered at 10 Hz, in 0.5 s bursts every 2 s for up to 3 days. Expression of GAP-43 was assessed by immunocytochemistry, two ELISA methods, and Northern blot analysis within three experimental protocols: (1) prior to synaptogenesis, (2) after synaptogenesis with spinal cord neurons, and (3) within the context of activity-dependent synaptic competition, in which synapses from active and inactive DRG neurons converge on the same postsynaptic neurons. None of the stimulation treatments produced a measurable change in GAP-43 or RNA message for the protein, although this electrical stimulus induces persistent changes in synaptic strength, and alters neurite outgrowth in these cultures. The decline in GAP-43 levels between 1 and 3 weeks in culture, which has been reported in other studies, was readily detectable by our measurements. We conclude that regulation of GAP-43 expression is not required for activity-dependent regulation of growth cone motility, synaptogenesis and synapse elimination, or changes in synaptic strength. Instead, post-translational modification, such as phosphorylation, may be the primary means of regulating any GAP-43 functions associated with these activity-dependent processes.

Animals↗

[Protective effect of electrical stimulating cerebellar fastigial nucleus on ischemia and reperfusion-injury of rat retina].

OBJECTIVE: To study the protective effect of electrical stimulating cerebellar fastigial nucleus on ischemia-reperfusion-injury of rat retina. METHODS: Rats were divided randomly into group of ischemia-reperfusion, group of electrical-stimulation-treated and group of sham-operated. The duration ischemia was 1 hour except sham-operated. In treated group, harvests of retinas followed electrical stimulation of cerebellar fastigial nucleus for 60 min after reperfusion for 6 hours; in reperfusion group, retinas were harvested only after 6 hours reperfusion. Retinal ischemia was produced in rats by ligating vessels and the optic nerve for 1 hour. Expression of inducible nitric oxide synthase (iNOS) in retina was measured by NADPH-NDP histochemistry; Apoptosis was measured by Tdt-dUTP terminal nick-end labeling (TUNEL) method. Morphology change was observed with the help of HPIAS-1000 auto-medical-imagined computer analyzer. RESULTS: (1) The thickness of inner retinal (including outer plexiform layer, inner nuclear layer, ganglion cell layer, optic nerve fiber and inner limiting membrane) and the inner plexiform layer were increased significantly in ischemia-reperfusion group than those in treated group. (2) The morphological changes of the scattered and condensed nucleus were observed more slightly under light microscopy in treated group than those in ischemia-reperfusion group. (3) Expression of inducible nitric oxide synthase (iNOS) in retinal ganglion cell in treated group is more significant than in ischemia-reperfusion group. (4) The amount of apoptosis cells in retina in treated group is significantly less than thatin ischemia-reperfusion group. CONCLUSIONS: (1) The results indicated that ischemia-reperfusion injury can induce retinal apoptosis. Retinal apoptosis can be inhibited by electrical stimulation cerebellar fastigial nucleus. (2) iNOS maybe involved in the mechanism of apoptosis. (3) Cerebellar fastigial nucleus electrical stimulation can protect ischemia-reperfused retina.

Animals↗