The effect of repetitious concussions on cognitive functions in rats

AIM

In this study, we aimed to investigate the effect of repetitious concussions on the spatial learning and memory function in rats.

MATERIAL AND METHODS

46 adult, male Sprague-Dawley rats were assigned to three homogenous groups by stratified random sampling according to their basal performance during the first four days of the Morris water maze (MWM), as Control (n=10), Sham (n=10) and Concussion (n=26) groups. On the 12th day, the MWM experiment was repeated to evaluate the memory function. Rats in the concussion group were then subjected to the first head trauma. Some of the trauma-applied rats were sacrificed for histopathological examination 4 hours (n=4) and 24 hours (n=3) after the trauma. The spatial memory function of the rest of the rats was re-evaluated by MWM on the 20th day. Some of the rats were then subjected to the second head trauma (n=13), four of which were then sacrificed at the 4th hour, and three of which were sacrificed at the 24th hour. On the 27th day, six rats that had received single concussion and the remaining six that had received two concussions were re-evaluated for retention development by the third MWM experiment.

RESULTS

Escape latency curves showed a decrease in Sham and Control groups on the 20th and 27th days, and an increase in concussion group on the 20th day but no statistical significance was found between the groups.

CONCLUSION

Repetitious concussions did not significantly affect spatial learning-memory functions in rats, and may lead to a counter-adaptive mechanism against concussive injury.

Clinical significance of TRAIL and TRAIL receptors in patients with head and neck cancer

BACKGROUND

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a death ligand currently under clinical trials for cancer. The molecular profile of TRAIL and TRAIL receptors has not yet been mapped for patients with laryngeal squamous cell carcinoma (SCC) or patients with oral cavity squamous cell carcinoma (OCSCC).

METHODS

Paraffin-embedded tissues from 60 patients with laryngeal SCC and 14 patients with OCSCC were retrospectively analyzed using immunohistochemistry.

RESULTS

An increase in decoy-R1 (DcR1) but a decrease in decoy-R2 (DcR2) expression were observed in patients with laryngeal SCC and in patients with OCSCC compared with control individuals with benign lesions. Clinical and pathologic grading revealed distinctive TRAIL and TRAIL receptor profiles in patients with squamous cell carcinoma of the head and neck (SCCHN).

CONCLUSIONS

TRAIL and a TRAIL receptor expression profile might be useful to follow-up disease progression by virtue of its connection with clinical staging and pathologic grading in patients with laryngeal SCC.

Fetal allogeneic umbilical cord cell transplantation improves motor function in spinal cord-injured rats

AIM

The objective of this study was to investigate whether the transplantation of fetal umbilical cord tissue cells as a source of stem cells into the acutely injured spinal cord would produce some regenerations and/or functional recovery in a rat model of spinal cord injury.

MATERIAL AND METHODS

Five pregnant albino Wistar rats of 12 days gestation were used for obtaining an umbilical cord cell graft. At the second stage of the experiment only Th8-Th9 laminectomy was performed in Group A animals while Group B animals underwent spinal cord hemitransection. The cultured fetal umbilical cord cells coated with Alginate Gel were placed into the lesion cavity immediately after surgery in Group C animals. Group D animals received only Alginate gel sponges into the injured area. All experiment groups were analyzed histologically and immunohistochemically (GFAP, Ki-67, and Pan cadherin) and for motor function after surgery.

RESULTS

The umbilical cord cell transplanted animals showed a significant motor recovery compared to non-transplanted animals at 8 and 21 days after spinal cord injury (p=0.008). Significant GFAP and Ki-67 expressions were noted in transplanted animals (p=0.048) suggesting astroglial proliferation.

CONCLUSION

Our findings support the possibility of some functional recovery after umbilical cord cell transplantation following spinal cord injury.

Immunohistochemical FHIT expression still exists in early lesions of basal cell carcinoma

In this study, we evaluated the expression of Fragile Histidine Triad (FHIT) in basal cell carcinoma (BCC). The FHIT locus was found to be altered in numerous types of cancer [6,7,18,20,22,25,26]. However, we found only one study dealing with FHIT expression in BCC [11]. In our study, we used immunohistochemical methods for the evaluation of FHIT expression in tissue samples of 42 BCC cases. The control group was formed by intradermal melanocytic nevi (IMN). Ki-67 labeling index was used to compare cellular proliferation of BCC with internal and external controls. The study group was further separated into two subgroups, according to the intensity of FHIT staining. The Ki-67 indexes of these subgroups were also compared with each other. As a primary result, there was no significant decrease in FHIT expression in early lesions of BCC. As a second finding, there was no correlation between the intensity of FHIT staining and Ki-67 labeling index. As a third finding, there was no difference in Ki-67 labeling index between early lesions of BCC and non-neoplastic epidermis. The results were unexpected, since FHIT expression has been reported to be lost in an above mentioned study [11]. We concluded that FHIT expression remains to be positive, at least in early lesions of BCC.

The diet of Clinitrachus argentatus (Blennioidei: Clinidae) in the northern Aegean and Marmara Seas

Differences in the diet composition of small (28-42 mm total length, L(T)) and large (43-75 mm L(T)) individuals of the cline Clinitrachus argentatus (Clinidae) were evident. Smaller individuals preyed mainly on copepods, whereas larger individuals ate mainly amphipods, isopods, brachyurans and polychaetes.

Evaluation of auditory brainstem potentials in children with acute Herpes simplex encephalitis

OBJECTIVE

In this study, auditory brainstem potentials (ABPs) were studied in children with Herpes simplex encephalitis (HSE) to determine the ABP abnormalities in HSE during childhood. We also wished to determine whether or not to use ABP in early diagnosis of HSE.

METHOD

The study includes 28 children; eight children with acute HSE, nine with nonspecific encephalitis, and 11 healthy age-matched control subjects. The diagnosis of HSE was confirmed by the demonstration of Herpes simplex virus type 1 in CSF by polymerase chain reaction. Recordings of ABPs were performed by using Nihon Kohden Neuropack 2 device.

RESULTS

The study includes eight children (four females and four males) with acute HSE, nine children (five males and four females) with nonspecific encephalitis, and 11 healthy age-matched control subjects (six males and five females). Age ranges of the patients and controls were between six months and 12 years. There was not statistically significant difference between the groups for age and gender (p > .05). There were significant differences in the mean latencies of the wave IV on the right ear and in the mean interpeak latencies (IPLs) of the waves III-V on the right and left ears between the nonspecific encephalitis group and the control group (p < .05). However, there were no statistically significant differences between the HSV and control groups (p > .05). In addition, there was no significant difference between HSV and nonspecific groups (p > .05).

CONCLUSIONS

Our findings revealed that there were mild ABP abnormalities in children with nonspecific encephalitis, but no ABP abnormality in patients with HSV encephalitis. However, we think that more extensive and detailed studies should be performed to determine whether or not there were ABP abnormalities in childhood HSV encephalitis.

Glioblastoma multiforme mimicking arteriovenous malformation

Glioblastoma multiforme is the most common intracranial neoplasm of all primary central nervous system tumors. Glial tumors can present in different forms. Intracranial hemorrhage may occur in all central nervous system tumors to a varying degree and extent and may even be massive. A 58-year-old man presented with intraparenchymal hemorrhage manifesting as severe headache and vomiting. Cranial computed tomographic scans revealed a right posterior temporoparietal intraparenchymal hemorrhage. Cerebral angiography revealed a 3 x 2 cm right inferior parietal arteriovenous malformation. The patient underwent surgical treatment with a diagnosis of arteriovenous malformation. Postoperatively, the histological diagnosis was glioblastoma. Glioblastoma may mimic an arteriovenous malformation. Close follow-up of such patients is essential.

INHIBIN B LEVELS IN PERIPHERAL VEIN DO NOT CORRELATE WITH INHIBIN B LEVELS IN THE SPERMATIC VEIN IN ADOLESCENTS WITH VARICOCELE

This study was conducted to evaluate the inhibin B with FSH and LH levels on spermatogenesis in varicocele patients. The study group consisted of 10 adolescent with left idiopathic varicocele of grade II and III. Blood specimens were obtained from dilated spermatic vein and peripheral vein simultaneously. Peripheral samples were also collected from 7 healthy children as controls. Inhibin B was measured with ELISA inhibin B kits. FSH and LH were analyzed by radioimmunoassay techniques. The results were analyzed using Mann-Whitney U and Spearman's rank tests. A value of p < 0.05 was considered significant. Peripheral FSH, LH and inhibin B levels were the same in the study and control group (p > 0.05). Mean inbibin B levels of spermatic vein were significantly higher than the control and peripheral blood of the study groups (p < 0.05). FSH, LH, and inhibin B levels correlated poorly each other (p > 0.05). Preoperative serum inhibin B concentration could not reliably predict a response to varicocelectomy, but the increase in inhibin B levels after treatment might suggest an improvement in testicular function.

Her-2/neu gene amplification in paraffin-embedded tissue sections of meningioma patients

AIM

Meningiomas arise from the meningoendothelial cells and are one of the most common tumors of the central nervous system. The HER-2/neu gene is located on the 17q11.2-q12 chromosome region and encodes an epidermal growth factor receptor. HER- 2/neu gene amplification and/or over expression have been studied most widely in breast carcinomas. Previous studies have shown the importance of HER-2/neu gene amplification on the prognosis of meningioma cases. In this study, we aimed to detect HER-2/neu gene copy number in archive materials of 55 meningioma patients by fluorescent in situ hybridization (FISH).

MATERIAL AND METHODS

The patients included in the study had undergone surgery in the neurosurgery department of our hospital between 1999 and 2002. Tissue samples were classified histologically according to WHO 2007 guidelines. Interphase FISH was performed on 3 to 4microm thick paraffin embedded tissue sections for the detection of HER- 2/neu gene amplification status.

RESULTS

We found HER-2/neu gene amplification in 7 (12.73%) patients. Another 2 patients had only one signal for the HER-2/neu region. We confirmed this finding by a second hybridization with the chromosome 17p13.1 (p53) probe.

CONCLUSION

According to our results, HER-2/neu amplification could be regarded as an additional genetic factor playing role in meningioma pathogenesis together with known chromosomal abnormalities.

Extraventricular neurocytoma--report of a case

Neurocytomas are typically located within the supratentorial ventricular system. Extraventricular neurocytoma is a rare brain tumour that poses diagnostic difficulty. We report a case of cerebral extraventricular neurocytoma. A 44-year-old man presented with a 6-month history of tonic-clonic seizures. Magnetic resonance imaging demonstrated a left frontoparietal mass lesion. The patient underwent surgical therapy, and a radical excision was performed. The histological appearance and immuno-histochemical findings of the tumour are consistent with an extraventricular neurocytoma with anaplastic features. An excellent prognosis can be expected if a gross total resection is achieved. Postoperatively, radiotherapy and chemotherapy may be used as adjuvant therapies.

Pap smear findings in chronic renal failure patients compared with the normal population according to Bethesda 2001

Dialysis remains the most common treatment for end-stage renal disease (ESRD). Although the increased risk of cancer after renal transplant is well documented, there is less certainty about the risk of cancer in patients treated only with dialysis. From 1997 to 2002, 262 ESRD patients received a Pap test at Başkent University. The smears of 149 patients who had ESRD for more than 9 months were compared with the smears of 150 otherwise healthy patients. All of the Pap smears were re-examined according to Bethesda 2001 criteria. The mean age of the patients was 42.88 years. Regarding micro-organisms, no statistically significant difference between the groups were observed. In 36 Pap smears, a shift in flora suggestive of bacterial vaginosis was detected. There were statistically significant differences between the groups. When age was considered as a marker of atrophy, atrophy in patients younger than 50 years was statistically different between the groups. Also, we determined that the shift in flora suggestive of bacterial vaginosis and atrophy in patients aged younger than 50 years did not depend on the length of hemodialysis. Of 13 patients (4.3%) who had epithelial cell abnormalities there were not statistically significant differences between the groups. In conclusion, according to our study, CRF seems not to be a predictive factor for cervical cancer. Shift in flora suggestive of bacterial vaginosis and atrophy in patients aged younger than 50 years might be the natural effects of uremia, and they appear not to be dependent on the length of the hemodialysis period.

Nogo-A inhibitory peptide (NEP1-40) increases pan-cadherin expression following mild cortical contusion injury in rats

BACKGROUND

Nogo-A is a myelin-associated neurite outgrowth inhibitory protein that limits elongation of central nerve fibers, neuronal regeneration and plasticity. We investigated the effect of delivering an inhibitory peptide that neutralizes Nogo-A on neuronal recovery following mild cortical contusion injury.

METHODS

41 rats were allocated into the control and NEP1-40 treatment groups. PBS was applied following trauma over the parietal cortex after opening the dura in the control group. NEP1-40 solution was immediately applied following trauma after opening the dura in the treatment group. Each group was further divided into 3 subgroups and sacrificed on the third, eighth, and 21st days after injury. The brains were removed for analysis.

RESULTS

Immunohistochemical staining of the injured cortex for pan-cadherin revealed a significant increase in staining in the NEP 1-40 treatment group at the 8th and 21st days after injury. Electron microscopic evaluation revealed better cytoarchitectural preservation in the axons of the animals treated with NEP 1-40.

CONCLUSION

We observed improved preservation of injured neurons after topical application of NEP 1-40 following mild cortical injury. Pan-cadherin expression may correlate with the recovery of neurons and axonal bodies. Electron microscopical findings confirmed better preservation of neuronal structures after NEP1-40 treatment. Pan-cadherin is a good marker for neuronal recovery after cortical injury.

Diagnostic pitfalls in the evaluation of fine needle aspiration cytology of the thyroid: correlation with histopathology in 260 cases

OBJECTIVES

Fine needle aspiration cytology (FNAC) of the thyroid is a non-invasive, cost-effective screening procedure that is valuable for distinguishing neoplastic lesions from non-neoplastic nodules. The aim of this study was to determine the diagnostic accuracy of FNACs performed at our institution by correlating FNAC results with histopathological diagnoses.

METHODS

Two hundred and seventy-one aspiration cytology specimens followed by thyroidectomy were included in the study, and the results of 260 adequate FNACs were compared with their histological diagnoses.

RESULTS

The sensitivity and specificity of thyroid FNAC for detecting neoplasia were 92.6% and 91.6%, respectively. There were 15 (5.7%) false positives and six (2.3%) false negatives.

CONCLUSIONS

The results showed that follicular cells that exhibit some of the features of papillary carcinoma could be observed in a cytology slide of Hashimoto's thyroiditis, leading to a diagnostic pitfall. In addition, cellularity and overlapping cytological criteria in hyperplasia might lead to a false diagnosis.

Tentorium schwannoma mimicking meningioma: an unusual location

A 60-year-old female was admitted to our clinic complaining of a long-lasting headache. Cranial magnetic resonance imagining examination of the patient revealed a 22x24 mm extra-axial, well-demarcated, mass lesion based on the left tentorium. The patient underwent a craniotomy and the tumor was totally excised with the adjacent tentorium. The histopathological examination of the tumor complied with the diagnosis of schwannoma. The rest of the clinical course was uneventful and the patient was released from the hospital without any neurological deficit. Intracranial schwannomas can rarely originate from atypical dural locations and radiological techniques are not always helpful in distinguishing tentorial schwannoma from tentorial meningioma. We presented a patient with a tentorium schwannoma mimicking meningioma and discussed the current literature.

Intraventricular dysembryoplastic neuroepithelial tumor: case report

OBJECTIVE

The most common localization of dysembryoplastic neuroepithelial tumors (DNTs) is the supratentorial cortex, often in the temporal lobe. However, intraventricular localization of a DNT is extremely rare.

CLINICAL PRESENTATION

A 30-year-old woman presented with a 1-year history of epileptic seizures. The seizures had not been controlled despite standard doses of antiepileptics.

INTERVENTION

Neuroimaging results demonstrated a lesion located in the occipital horn of the right lateral ventricle. The lesion was totally removed. Based on histopathological and immunohistochemical evaluation, a DNT was diagnosed. Over the course of the next 8 months, the patient's epileptic seizures were under control. The most recent neuroimaging examinations revealed neither residual nor recurrent tumor.

CONCLUSION

Because DNTs are surgically curable and neither radiotherapy nor chemotherapy is required after surgery, recognition of an intraventricular DNT in this location is extremely important.

The accuracy and diagnostic yield of computerized tomography guided stereotactic biopsy in brain lesions

OBJECTIVES

Radiological imaging techniques provide early detection of neurological diseases but they do not always provide an adequate and reliable diagnosis. With the help of stereotactic biopsy techniques, it is possible to access brain lesions safely and with high precision. We described the surgical method used in our clinic and discussed our results with the help of the current literature.

METHODS

Ninety-four patients underwent computerized tomography-guided stereotactic brain biopsy in our clinic. Anatomical locations, diagnostic yield and accuracy of the procedure, morbidity and mortality rates were analyzed.

RESULTS

A total of 100 stereotactic surgery procedures were performed on 94 patients. The localizations of the lesions were 13.83% frontal, 21.27% temporal, 27.66% parietal, 4.25% occipital, 4.25% multiple, 27.66% deep seated and 1.06% suprasellar. The histopathological diagnoses were 61.71% neuro-epithelial tumors, 8.51% metastases and 10.64% infectious lesions. Diagnostic yield was 86.16% and the accuracy was 90% in our series.

CONCLUSION

Computerized tomography-guided stereotactic brain biopsy is a reliable and safe method. Main diagnostic problems in SBB are tissue heterogeneity, insufficient material and sampling error. These problems can be minimized by careful correlation of clinical, radiological and histopathological findings by an experienced team and by using modern technologies.

Antibodies neutralizing Nogo-A increase pan-cadherin expression and motor recovery following spinal cord injury in rats

STUDY DESIGN

A rat model of spinal cord injury was used to test the hypothesis that Nogo-A monoclonal antibody (NEP1-40) promotes morphologic and functional recoveries of injured spinal cord.

OBJECTIVE

Nogo-A is a myelin-associated neurite outgrowth inhibitory protein, which blocks elongation nerve fibers and limits neuronal regeneration after central nervous system injury.

METHODS

Forty-four rats were utilized and allocated into control (vehicle) and NEP1-40-treated groups. In all animals, the spinal cord was hemi-transected at Th-10 and phosphate-buffered saline solution was immediately applied on the injured area in the control group. NEP1-40 solution was immediately applied on the hemi-transected area in the treatment group. Each group was subdivided into three subgroups according to the postsurgical day of killing (3, 8 and 21 days). The spinal cords were removed for analysis.

RESULTS

Motor scores in the NEP1-40-treated groups were significantly higher than those in the vehicle groups both at 8 and 21 days post injury. Immunohistochemical staining for pan-cadherin, a marker of neuronal cell adhesion and axonal sprouting, revealed a significant increase in staining in the NEP1-40 treatment group at 8 and 21 days post injury. Transmission electron microscopical evaluation revealed degeneration of the myelin and loss of cytoarchitectural organization in the axons of controls. Better preservation and normal histologic features were observed in the NEP1-40-treated groups.

CONCLUSION

We have demonstrated improved preservation of injured axons and significant pan-cadherin expression after NEP1-40 treatment after the spinal cord injury. Inhibition of Nogo-A may improve the capacity for neuronal regeneration after spinal cord injury.

Expression of p53 in lesions and unaffected skin of patients with plaque-type and guttate psoriasis: A quantitative comparative study

Psoriasis is a common inflammatory and hyperproliferative skin disease characterized by hyperproliferation of keratinocytes. The pathogenesis of psoriasis has yet to be determined. The control of cell growth is a delicately balanced process, regulated by external signals or the internal genetic program of an individual cell. In psoriasis, these processes are disturbed and some candidate genes like p53 are suspected of being involved in the pathogenesis of the disease. The p53 protein is essential for the regulation of cell proliferation. The study was performed on 32 patients with psoriasis (24 plaque type, eight guttate type). Biopsy specimens for immunohistochemical determination of p53 protein expression were collected from both the lesional and the nonlesional skin sites that were not exposed to sun in all of the patients (n = 32). Taking the ultraviolet (UV) exposure of the skin into consideration, a third skin sample was taken from each patient (n = 7) who had lesions on the sun-exposed areas. Immunohistochemical assessment of p53 expression in skin was determined as p53 protein expression per 1000 cells (keratinocytes). The statistical analysis revealed that the expressions of p53 per 1000 cells were higher in non-sun-exposed lesional skin than the non-sun-exposed nonlesional skin, also in plaque-type psoriasis than guttate-type psoriasis (P = 0.000, P = 0.046, P = 0.037, respectively). There was a positive correlation between the p53 expression in non-sun-exposed lesional skin versus expression in sun-exposed lesional skin (cubic centimeters = 0.811, P = 0.027). Our results show a stronger association of elevated p53 expression with chronic rather than acute inflammatory psoriasis. This may indicate a mechanistic difference between plaque-type and guttate psoriasis. Alternatively, this could reflect a chronological course as the disease transitions from an acute to a chronic phase.

Spinal drop metastasis of choroid plexus papilloma

A rare case of choroid plexus papilloma (CPP) with spinal drop metastasis is presented. A 51-year-old woman was operated on for a tumor of the fourth ventricle with histopathological diagnosis of CPP. Seven years later, she was re-admitted with low back pain. MRI showed multilobulated tumor at the lumbosacral subarachnoidal space with histopathological diagnosis of CPP. Thus, CPP can spread via the cerebrospinal fluid pathways and cause drop metastasis.

Impact of aromatase inhibitors on adhesion formation in a rat model

OBJECTIVE

To investigate the antiadhesion potential of tamoxifen and anastrozole in a rat uterine horn model.

DESIGN

Experimental animal study.

SETTING

University animal laboratory.

ANIMAL(S)

Forty-five female Wistar albino rats.

INTERVENTION(S)

We examined the effects of tamoxifen and anastrozole to reduce the extent and severity of postoperative adhesions in a rat uterine horn model: the control group received no therapy while the second and third groups received 500 mug/day tamoxifen and 0.2 mg/kg/day anastrazole, respectively, through an enteric tube, starting 5 days before surgery. These protocols were continued for 14 days after the surgery until the rats were killed.

MAIN OUTCOME MEASURE(S)

Adhesions were scored according to their extent and severity, and specimens were also evaluated and scored histologically according to the following features: inflammation, fibroblastic activities, foreign body reaction, collagen formation, and vascular proliferation.

RESULT(S)

Anastrozole had the lowest mean adhesion scores, and these scores were significantly different from those of the controls. However, there were no statistically significant differences between control and tamoxifen groups and between tamoxifen and anastrozole groups. Histologic scores were lowest in the anastrozole group, which were statistically different from those of the tamoxifen and anastrozole groups, whereas scores of the control group were not statistically different from those of the tamoxifen group.

CONCLUSION(S)

Anastrazole decreased postsurgical adhesion scores by both visual scores and histologic analyses in a rat model. Further experimental and clinical trials are required to confirm these results.

Treatment of Morgagni hernias by transabdominal approach

BACKGROUND

Recently, the thoracic approach has been suggested in the surgical treatment of Morgagni hernias with some reported advantages over abdominal surgery. This manuscript reports the authors' experience with childhood Morgagni hernias repaired via laparotomy.

SUBJECTS AND METHODS

Records of five cases of Morgagni hernias were evaluated with respect to age, presentation, operative data, complications, and outcome.

RESULTS

The average age of four male and one female patients was 34 months (range 6 months to 8 years). Predominant presenting symptoms were related to the respiratory system. The diagnoses were made by posterior-anterior and lateral chest X-rays and confirmed by barium enema contrast radiographs. Associated anomalies were detected in three cases. All cases were managed by abdominal approach through upper midline incisions reducing the herniated viscera (transverse colon in all and including omentum in one patient) and excising the hernia sac which was present in all patients. The postoperative period was uneventful in this series and no recurrence was detected in an average of four years of follow-up.

CONCLUSION

The transabdominal approach is appropriate in the surgical correction of paediatric Morgagni hernias.

The effect of mexiletine on the level of lipid peroxidation and apoptosis of endothelium following experimental subarachnoid hemorrhage

OBJECTIVE

The role of apoptosis in etiopathogenesis of vasospasm is not clearly understood yet. It is widely accepted that protection of the endothelial cells from the process of apoptosis could have beneficial effects on cerebral vasospasm after subarachnoid hemorrhage (SAH). Mexiletine blocks sodium and calcium channels and activates ATP-sensitive K(+) channels. Moreover, mexiletine is known to have potent antioxidant effects through inhibiting free-radical production.

METHODS

Twenty-one rabbits were allocated into three groups randomly. Group I was sham operated group (n=7). SAH occurred but no medication was given to the Group II rabbits (SAH only group) (n=7). Mexiletine (50 mg/kg, b.i.d., i.p.) was administered just before SAH and continued until 48 hours following SAH to the Group III rabbits (Mexiletine treated group) (n=7). The ApopTag peroxidase in situ apoptosis detection kit (Serologicals Corporation, former Intergen) was used to demonstrate apoptosis in a cross section of basillary arteries. Thiobarbituric acid reactive material was used to determine the lipid peroxidation levels.

RESULTS

There was a statistically significant difference between lipid peroxidation product levels of the control and SAH only groups (p<0.05). The level of lipid peroxidation production in Mexiletine treated group was significantly lower compared with SAH only group (p<0.05) but not significantly higher than the control group (p>0.05).

DISCUSSION

In the present study we investigated the antioxidant action of mexiletine on apoptosis of endothelium following a rabbit SAH model. This experimental study directly suggested that lipid peroxidation is an important step in development of apoptosis in endothelial cells and prevention of structural integrity of endothelial cell should play a beneficial role in attenuation of cerebral vasospasm. Mexiletine treatment prevented the increase in lipid peroxidation and cerebral vasospasm. Examination of endothelial cells by staining specific for apoptosis demonstrated significant protection of cell integrity in the treated group.