International Journal of Neuroscience

DEMIR, NECDET; AKKOYUNLU, GOKHAN; AGAR*, AYSEL; YARGICOGLU**, PIRAYE; TANRIOVER, GAMZE; DEMIR, RAMAZAN

doi: 10.1080/00207450290025815pmid: 12424820

The present study demonstrated the ultrastructural effects of diabetes and cadmium on the peripheral nervous system. In this study we used 52 healthy Swiss male albino rats. They were divided into four groups: control (C), diabetic (D), cadmium (Cd), and diabetic and cadmium (D+Cd). The diabetic condition was induced by intravenous injection of 5 mg alloxan/100 g body weight, via the caudal vein. Cd and D+Cd groups were injected with CdCl2 intraperitoneally (2 mg/Kg/week) for two months. At the end of the experimental period, animals were sacrificed and their sciatic nerves were dissected. The tissue samples were investigated by using light and electron microscopic techniques. Upon investigation, it was seen that myelinated axons in sciatic nerve of diabetic and Cd treatment groups had onion-bulb type myelin destruction, melting, and protrusion. Basal lamina of capillary endothelia of D, Cd, and D+Cd groups were thickened and the endothelial apical membrane was rough. In conclusion, Cd toxicity exacerbated the destructive effect of diabetes on the peripheral nervous system.

KURUP, RAVI KUMAR; KURUP, PARAMESWARA ACHUTHA

doi: 10.1080/00207450290025824pmid: 12424821

The isoprenoid pathway related cascade was assessed in 15 patients with obsessive compulsive disorder (OCD) and la Tourette s syndrome (TS). The pathway was also assessed in right hemispheric dominant, left hemispheric dominant, and bihemispheric dominant individuals to assess whether hemispheric dominance has any correlation with these disease states. The levels of serum digoxin, HMG CoA reductase activity, and dolichol were found to be decreased in OCD and la Tourette s syndrome as well as in left hemispheric dominant individuals with a corresponding increase in RBC Na &#180 +;-K &#180 +; ATPase activity, serum ubiquinone, and magnesium levels. There was an increase in tyrosine and its catabo lites, and a reduction in tryptophan and its catabolites in the serum. The total and individual glycosaminoglycan (GAG) fractions, carbohydrate residues of glycoproteins, and the concentration of glycolipids decreased in the serum. The activity of GAG degrading enzymes and glycohydrolases were decreased. The RBC membrane glycoconjugates were increased while the membrane cholesterol:phospholipid ratio was decreased. The activity of free radical scavenging enzymes increased while the concentration of free radicals decreased significantly. On the other hand, there was hyperdigoxinemia and the reverse biochemical patterns in those with right hemispheric dominance. Membrane Na &#180 +;-K &#180 +; ATPase stimulation can result in decreased intracellular Ca &#180 2+; and increased magnesium levels. Increased levels of dopamine can lead to a tic syndrome, while reduced levels of serotonin and increased dopamine can both lead to obsessive compulsive disorder. Decrease in fucose and sialo-ligands, increased immunosuppressive morphine levels, decreased T-cell calcineurin signal transduction related to decreased intracellular calcium, reduced free radical production, and altered presentation of bacterial glycoconjugate antigens can lead to a hypoimmune response and recurrent respiratory infection in OCD patients. OCD and la Tourette s syndrome are associated with left hemispheric chemical dominance.

BILICI, MUSTAFA; CAKIRBAY, HASIM; GULER, MUSTAFA; TOSUN, MEHMET; ULGEN, METIN; TAN, UNER

doi: 10.1080/00207450290025833pmid: 12424822

There are some reports that classical neuroleptics may lead to osteoporosis or reduced bone mineral density (BMD). However, there is no adequate information about the effects of atypical neuroleptics on BMD. The aim of this study was to measure BMD in schizophrenic patients taking class -ical and atypical neuroleptics, compared to healthy controls. Seventy- five patients with schizophrenia (40 taking classical neuroleptics [CN], 35 taking atypical neuroleptics [AN]) and 20 healthy controls (HC) were included in the study. Spine (L1 L4) BMD was measured by dual-energy X-ray absorptiometry. ANOVA showed that BMD was higher in HC than AN and CN. In addition, there was a negative correlation between the duration of neuroleptic treatment and BMD and the duration of the illness. These findings suggest that atypical neuroleptics may be safer than the classical neuroleptics in terms of reduced BMD.

DAGCI, T.; TAN, M.; KOYLU, E. O.; TAN, U.; POGUN, S.

doi: 10.1080/00207450290025842pmid: 12424823

Systemic kainic acid (KA) administration to rats triggers wet dog shakes (WDS) followed by epileptic seizures. Although WDS are often associated with the occurrence of seizures, we have recently shown that following nitric oxide (NO) synthesis inhibition, the number of WDS decreased; subsequently the onset of seizure activity was shortened, and the number of convulsions was increased. Somatostatin (SS), whose release appears to be controlled by NO, inhibits seizure activity. There are sex differences in seizure susceptibility as well as in SS and NO activities in brain. The present study was undertaken to assess the effect of octreotide (OC), a stable SS analogue, on KA-induced WDS and seizures in rats, with emphasis on possible sex differences. WDS and seizures were induced by KA in male and female (proestrus) Sprague Dawley rats; OC or saline was injected 30 min before KA and the behavior was monitored for 120 min after KA. Octreotide increased the number of WDS and decreased the number of convulsions; this effect was more pronounced in males. Onset of KA-induced seizure ac tivity was earlier in females than males; however, there was no effect of OC on seizure latency. Seizure activity started after the termination of WDS. These results show OC has opposite effects on WDS and convulsions, in that it stimulates the former and inhibits the latter. These results support our previous findings that WDS and seizure activity involve separate mechanisms and suggest that WDS may have an inhibitory effect on limbic seizures.

PALMIERI, RIANN M.; HOFFMAN, MARK A.; INGERSOLL, CHRISTOPHER D.

doi: 10.1080/00207450290025851pmid: 12424824

The Hoffmann reflex (H-reflex) has been widely used throughout neuroscience research, as it allows for the assessment of alpha motoneuron excit ability arising from a specific motoneuron pool. Recently, a protocol has been developed allowing for the simultaneous examination of the soleus, peroneal, and tibialis anterior motoneuron pools elicited from a single peripheral stimulus. In order for this protocol to be useful, the reliability of the measures must be established. The purpose of the current study was to determine the intersession reliability of the soleus, peroneal, and tibialis anterior H-reflexes and their corresponding M-waves elicited from a single stimulus to the sciatic nerve. Ten healthy neurologically sound individuals (age: 23 &#45 7 yrs; height: 175 &#45 12 cm; mass: 76 &#45 22 kg) volunteered to participate in this investi gation. To obtain the measurements, the sciatic nerve was stimulated just prior to its bifurcation into the tibial and common peroneal nerves in the popliteal fossa. A 1-ms square wave pulse was delivered in 0.2V increments until the maximum M wave was seen in each muscle. The maximum H-reflex and M-waves were collected from each muscle and their ratios calculated. Intersession reliability over 2 consecutive days was estimated using intraclass correlation coefficients (ICC [2,1]). Intersession reliability for the soleus Max H, Max M, and H:M ratio were 0.9953, 0.9514, and 0.9747, respectively. The peroneal reliability measurements were as follows: 0.9979 (Max H), 0.9924 (Max M), and 0.9664 (H:M ratio). Intersession reliability was 0.8591, 0.9968, and 0.7810 for the tibialis anterior Max H, Max M, and H:M ratio, respectively. These results indicate that the H-reflex measured from the soleus, peroneal, and tibialis anterior musculature elicited with a single peripheral stimulus to the sciatic nerve is reliable between sessions. This protocol allows the clinician/researcher to reliably investigate the alpha motoneuron excitability of multiple motoneuron pools about the ankle at a single point in time.

ALLAM, MOHAMED FAROUK; DEL CASTILLO, AMPARO SERRANO; NAVAJAS, RAFAEL FERNÁANDEZ-CREHUET

doi: 10.1080/00207450290025860pmid: 12424825

A systematic review was conducted to estimate the pooled risk of smoking for Parkinson s disease in Chinese populations. The four identified case-control studies had odds ratios with 95% confidence intervals nearly or overlapping unity. Pooled odds ratio of these studies was 0.77 with 95% confidence interval 0.60 to 0.97. It was suggested that smoking induces debrisoquine 4-hydroxylase, which is responsible for the metabolism of antipsychotic drugs and the detoxification of certain environmental toxins known to cause dopaminergic neural damage. This could be the explanation of these contradictory results as cytochrome P-450 CYP2D6 debrisoquine hydroxylase gene polymorphism is known to be much lower in Chinese than in Caucasian people. This systematic review raises concerns about generalization of the conclusion previously settled by many cohort and case-control studies.

BON, LEOPOLDO; LUCCHETTI, CRISTINA; PORTOLAN, FLAVIO; PAGAN>, MAURO

doi: 10.1080/00207450290025888pmid: 12424826

The aim of this article was to describe an apparatus, called multipurpose neck robot (MUPRO), designed to record both the forces exerted at head level and the head rotations in the horizontal plane in the behaving monkey. It consists of a mechanical device, comprising a cardan joint, a potentiometer, an electromagnetic brake, and four flexion load cells, plus an oleodynamic system allowing head rotation in the horizontal plane between &#45 20° These components are assembled on a column bolted to the primate s chair. An electrical device provides DC power for the potentiometer and the brake. The apparatus enables us to measure both the force fields and the head movements during training sessions and electrophysiological investigations.

MAROSI, ERZSÉBET; BAZÁN, OSCAR; YAÑEZ, GUILLERMINA; BERNAL, JORGE; FERNÁNDEZ, THALÍA; RODRÍGUEZ, MARIO; SILVA, JUAN; REYES, ALFONSO

doi: 10.1080/00207450290025897pmid: 12424827

The objective of this study was to discover how narrow-band spectral measurements express emotional behavior. Electroencephalographic narrow-band absolute and relative spectral powers were calculated for every 1 Hz of frequency from the recordings of 40 healthy male university students during emotional tasks. Sentences evoking positive, negative, and neutral emotional states were used as stimuli. Repeated multivariate analyses of variance were computed with IQ as covariate. The results showed only a few significant relations between absolute power and emotion. Relative power reflected better the differences determined by emotional states. The frequencies between 7.6 and 9.5 Hz showed differ -ences between emotional states over the entire scalp with increased power during neutral state. Interaction between emotional states and cerebral regions revealed that all cerebral areas had an important role, especially frontal, parietal, and temporal regions. Hemispheric differences showed less power in the left hemisphere during positive emotional state (joy of love) in the 8.6 to 9.5 Hz band and in the right hemisphere during negative emotional state (frustration) in the 17.6 to 18.5 Hz band. Significant interaction between states, hemispheres, and electrode positions was observed in the frequency range of 17.6 to 19.5 Hz. As none of our results covered the range of any broad band, we may conclude that narrow-band calculations are more adequate for the study of emotions, because their use reduces the danger that frequency-specific effects go undetected or cancel each other.

FELL, JÜRGEN; ELFADIL, HAKIM; RÖSCHKE, JOACHIM; BURR, WIELAND; KLAVER, PETER; ELGER, CHRISTIAN E.; FERNÁNDEZ, GUILLÉN

doi: 10.1080/00207450290025905pmid: 12424828

The EEG during deep sleep exhibits a distinct cortically generated slow oscillation of around and below 1 Hz which can be distinguished from other delta (0.5 3.5 Hz) activity. Intracranial studies showed that this slow oscillation triggers and groups cortical network firing. In the present study, we examined whether the phases of the slow oscillation during sleep stage 4 are correlated with the magnitude of sigma (12 16 Hz) and gamma (>20 Hz) scalp activity. For this purpose, 10-min segments of uninterrupted stage 4 sleep EEG from 9 subjects were analyzed by applying wavelet techniques. We found that scalp recorded sigma, but not gamma, activity is modulated by the phases of the slow oscillation during deep sleep. Enhancement of sigma activity was observed to be triggered by the peak of the surface positive slow wave component, whereas reduction of sigma activity started around the peak of the negative component.