Effect of Serum from Schizophrenics on Evoked Cortical Potentials in the Rat

1965 ◽  
Vol 111 (473) ◽  
pp. 339-344 ◽  
Author(s):  
D. Stenhouse ◽  
R. Antebi ◽  
E. M. A. Dear ◽  
R. N. Herrington ◽  
C. McCance
Keyword(s):  
Cerebral Cortex ◽  
Rat Cerebral Cortex ◽  
Sensory Area ◽  
Normal Individuals ◽  
Schizophrenic Patients ◽  
Evoked Cortical Potentials ◽  
Stimulation Of ◽  
Cortical Potentials

German (1961, 1963) reported that serum from schizophrenic patients, in contrast to that from normal individuals and non-schizophrenic patients, when applied topically to the rat cerebral cortex, increased the amplitude of potentials evoked in the somato-sensory area by stimulation of the contralateral forepaw. Furthermore, similar changes were found when urine extracts were tested in the same manner (German and Kemali, 1963; Kemali, 1964).

Effects of Serum from Schizophrenics on Evoked Cortical Potentials in the Rat

1963 ◽  
Vol 109 (462) ◽  
pp. 616-623 ◽  
Author(s):  
G. A. German
Keyword(s):  
Cerebral Cortex ◽  
Clinical Picture ◽  
Biological Systems ◽  
Mental Condition ◽  
Biochemical Processes ◽  
Schizophrenic Patients ◽  
Evoked Cortical Potentials ◽  
Cortical Potentials

Many experiments have been reported suggesting that the serum of schizophrenic patients differs in some way from the serum of non-schizophrenic subjects, either in respect of some specific constituent or of the alterations in function which it can produce when added to various biological systems (Heath, 1957; Walaszek, 1960; Bergen, Koella, Czicman and Hoagland, 1961). These reports suggest that schizophrenia is a pathological mental condition resulting from some disorder of metabolism or of biochemical processes, and it would be logical to expect that this disorder would be most manifest as a disturbance of the neurological activity in the cerebrum—perhaps more specifically in the cerebral cortex—since the clinical picture in schizophrenia is primarily one of gross derangement of the processes of perception, attention and thinking.

A Further Study of the Effects of Serum from Schizophrenics on Evoked Cortical Potentials in the Rat

1965 ◽  
Vol 111 (473) ◽  
pp. 345-347 ◽  
Author(s):  
G. A. German ◽  
R. N. Antebi ◽  
E. M. A. Dear ◽  
C. McCance
Keyword(s):  
Cerebral Cortex ◽  
Electrical Response ◽  
Cutaneous Stimulation ◽  
Control Subjects ◽  
Schizophrenic Patients ◽  
Evoked Cortical Potentials ◽  
Cortical Potentials

In 1963, one of us reported that serum from schizophrenic patients, applied topically to the cerebral cortex of the rat, produced a large increase in the amplitude of the electrical response evoked in the cortex by cutaneous stimulation (German, 1963). This effect was not observed when serum from non-schizophrenic control subjects was used.

Stable Abnormalities in the Lateralisation of early Cortical Somatosensory Evoked Potentials in Schizophrenic Patients

1985 ◽  
Vol 146 (6) ◽  
pp. 585-593 ◽  
Author(s):  
J. E. Cooper ◽  
H. Andrews ◽  
C. Barber
Keyword(s):  
Evoked Potentials ◽  
Somatosensory Evoked Potentials ◽  
Tactile Stimulus ◽  
The Other ◽  
Technical Problems ◽  
Affective Illness ◽  
Schizophrenic Patients ◽  
Evoked Cortical Potentials ◽  
Stimulation Of ◽  
Cortical Potentials

SummaryDuring the investigation of somatosensory evoked cortical potentials arising from a complex vibro-tactile stimulus to the forefingers, an abnormal lack of lateralisation of response was found in 10 out of 21 schizophrenic patients. Eight patients with severe affective illness all had the expected degree of lateralisation of cortical potentials, as did 12 out of 15 normals. Three normals and 3 schizophrenic patients had a loss of lateralisation of the evoked response on stimulation of one hand but a normal lateralisation on stimulation of the other. The considerable technical problems of this and related techniques are discussed, but it is suggested that further exploration of this technique is justified. At this stage, no conclusion can be drawn about the cause of the abnormalities.

HIGH-FREQUENCY MONOPOLAR ELECTRICAL STIMULATION OF THE RAT CEREBRAL CORTEX

Neurosurgery ◽  
2007 ◽  
Vol 60 (1) ◽  
pp. 189-197 ◽  
Author(s):  
Masahiro Oinuma ◽  
Kyouichi Suzuki ◽  
Takashi Honda ◽  
Masato Matsumoto ◽  
Tatsuya Sasaki ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Electrical Stimulation ◽  
High Frequency ◽  
Rat Cerebral Cortex ◽  
Stimulation Of

EGTA-sensitive and -insensitive forms of particulate adenylate cyclase in rat cerebral cortex: regulation by divalent cations and GTP

1985 ◽  
Vol 63 (8) ◽  
pp. 1007-1016 ◽  
Author(s):  
P. V. Sulakhe
Keyword(s):  
Enzyme Activity ◽  
Cerebral Cortex ◽  
Adenylate Cyclase ◽  
Gray Matter ◽  
Rank Order ◽  
Divalent Cations ◽  
Rat Cerebral Cortex ◽  
Chloride Salt ◽  
Low Concentrations ◽  
Stimulation Of

Interactions of several divalent cations (Mn2+, Ca2+, Co2+, Sr2+, and Zn2+) with EGTA-inhibitable adenylate cyclase were investigated in washed membranes (particles) isolated from the gray matter of rat cerebral cortex. The EGTA-inhibitable (called sensitive) enzyme activity was assayed in the presence of Triton X-100 since this detergent caused a marked increase (up to 20-fold) in the enzyme activity. The effects of various divalent metals (all added as chloride salt) indicated the presence of two distinct sites called site I and site II. At low concentrations (less than micromolar) Mn2+, Co2+, and Ca2+ increased (up to 10-fold) the enzyme activity to the same extent and appeared to act via binding to site I (high affinity site). The rank order of affinity was Mn2+ ≥ Co2+ > Ca2+. Zn2+ showed the highest affinity and Sr2+ the lowest towards binding to site I; both these metals increased the enzyme activity to lesser extents than Mn2+, Co2+, or Ca2+. GTP was not required for the stimulation of this enzyme by low concentrations of Ca2+. The interaction of Mn2+ with site II (low affinity site) caused further increase in the enzyme activity, whereas Co2+, Ca2+, and Sr2+ were inhibitory at concentrations >10 μM. Isolated fraction contained loosely and tightly associated pools of calmodulin. Myelin basic protein, but not calcineurin, inhibited the EGTA-sensitive adenylate cyclase activity. The EGTA-insensitive enzyme activity was increased by norepinephrine by mechanisms that depended on GTP and was inhibited by Ca2+. The stimulation of the EGTA-insensitive enzyme modulated the Mg2+ requirement such that Mg2+ binding to the low affinity site (site II) apparently occurred with higher affinity. The likely significance of these results is discussed with regard to (i) the presence of two classes of adenylate cyclase in rat cerebral cortex gray matter and (ii) the regulation of their activities by calmodulin-requiring and GTP-requiring mechanisms.

Monocular and Binocular Visual Evoked Potentials before and after Cataract Surgery

1979 ◽  
Vol 49 (3) ◽  
pp. 699-704
Author(s):  
J. L. Andreassi ◽  
S. S. Zalkind ◽  
J. A. Gallichio ◽  
N. E. Young
Keyword(s):  
Evoked Potentials ◽  
Cataract Surgery ◽  
Visual Evoked Potentials ◽  
Mature Cataract ◽  
Before And After ◽  
Evoked Cortical Potentials ◽  
Stimulation Of ◽  
Visual Evoked ◽  
Cortical Potentials

Visual evoked cortical potentials (VEPs) were recorded from an individual with a mature cataract in one eye. Stimulation was both monocular and binocular and VEPs were obtained from three occipital scalp sites. Comparisons of recordings taken prior to cataract removal and after removal showed a dramatic increase in amplitude of potentials derived through stimulation of the affected eye. Slight differences in hemispheric amplitude prior to surgery suggest a greater degree of opacity in one portion of the affected lens.

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