Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats
We examined the biocompatibility of carbon nanotubes (CNTs) injected i.p. into rats (1 mg/kg body mass) by recording EEG from the frontal and occipital cortex and performing the water maze router test before and after such injection. For EEG, the energy and average power spectral density of wavel...
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Інститут фізіології ім. О.О. Богомольця НАН України
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irk-123456789-1482022019-02-18T01:23:48Z Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats Azimirad, V. Hosseinpour, M. Shahabi, P. Alimohammadi, M. Sadighi, M. Hatami, H. We examined the biocompatibility of carbon nanotubes (CNTs) injected i.p. into rats (1 mg/kg body mass) by recording EEG from the frontal and occipital cortex and performing the water maze router test before and after such injection. For EEG, the energy and average power spectral density of wavelet coefficients in the β, α, and θ bands were considered the features. In the water maze router experiment, the distance, time, and speed of rats were investigated as behavioral factors. Comparison of EEG signals before and after injection showed that introduction of CNTs exerted no significant effect on electrophysiological brain indices. A comparison of behavioral factors before and after injection, however, showed that injections of CNTs increased the pacing distance and time to find the desired platform and decreased somewhat the speed in the water maze router experiment. A possible reason of this phenomenon is the possible influence of CNTs on ion fluxes in brain neurons. Ми досліджували біосумісність вуглецевих нанотрубок (ВНТ), ін’єкованих щурам (1 мг/кг маси тіла, внутрішньоочеревинно), відводячи ЕЕГ та застосовуючи поведінковий тест із водним лабіринтом перед такою ін’єкцією та після неї. Параметрами ЕЕГ вважали енергію та усереднені щільності спектральної потужності вейвлет-коефіцієнтів для бета-, тета- та альфа-ритмів. В експерименті з водним лабіринтом поведінковими факторами були відстань, час та швидкість руху щурів у пошуках цільової платформи. Порівняння сигналів ЕЕГ перед ін’єкцією ВНТ та після неї показало, що введення нанотрубок істотно не впливало на електрофізіологічні показники мозку. Порівняння ж поведінкових показників перед ін’єкцією та після неї, проте, засвідчило, що введення ВНТ викликало вірогідне збільшення шляху до платформи і тривалості її пошуків, а також деяке зменшення швидкості пересування у водному лабіринті. Можливою причиною такого феномену є вплив ВНТ на іонні токи в нейронах мозку. 2015 Article Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats / V. Azimirad, M. Hosseinpour, P. Shahabi, M. Alimohammadi, M. Sadighi, H. Hatami // Нейрофизиология. — 2015. — Т. 47, № 3. — С. 240-247. — Бібліогр.: 41 назв. — англ. 0028-2561 http://dspace.nbuv.gov.ua/handle/123456789/148202 616–71 en Нейрофизиология Інститут фізіології ім. О.О. Богомольця НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| language |
English |
| description |
We examined the biocompatibility of carbon nanotubes (CNTs) injected i.p. into rats (1 mg/kg
body mass) by recording EEG from the frontal and occipital cortex and performing the
water maze router test before and after such injection. For EEG, the energy and average
power spectral density of wavelet coefficients in the β, α, and θ bands were considered the
features. In the water maze router experiment, the distance, time, and speed of rats were
investigated as behavioral factors. Comparison of EEG signals before and after injection
showed that introduction of CNTs exerted no significant effect on electrophysiological brain
indices. A comparison of behavioral factors before and after injection, however, showed that
injections of CNTs increased the pacing distance and time to find the desired platform and
decreased somewhat the speed in the water maze router experiment. A possible reason of this
phenomenon is the possible influence of CNTs on ion fluxes in brain neurons. |
| format |
Article |
| author |
Azimirad, V. Hosseinpour, M. Shahabi, P. Alimohammadi, M. Sadighi, M. Hatami, H. |
| spellingShingle |
Azimirad, V. Hosseinpour, M. Shahabi, P. Alimohammadi, M. Sadighi, M. Hatami, H. Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats Нейрофизиология |
| author_facet |
Azimirad, V. Hosseinpour, M. Shahabi, P. Alimohammadi, M. Sadighi, M. Hatami, H. |
| author_sort |
Azimirad, V. |
| title |
Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats |
| title_short |
Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats |
| title_full |
Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats |
| title_fullStr |
Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats |
| title_full_unstemmed |
Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats |
| title_sort |
effects of injection of carbon nanotubes on eeg and results of a behavioral test in rats |
| publisher |
Інститут фізіології ім. О.О. Богомольця НАН України |
| publishDate |
2015 |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/148202 |
| citation_txt |
Effects of Injection of Carbon Nanotubes on EEG and Results of a Behavioral Test in Rats / V. Azimirad, M. Hosseinpour, P. Shahabi, M. Alimohammadi, M. Sadighi, H. Hatami // Нейрофизиология. — 2015. — Т. 47, № 3. — С. 240-247. — Бібліогр.: 41 назв. — англ. |
| series |
Нейрофизиология |
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| first_indexed |
2025-07-12T18:36:10Z |
| last_indexed |
2025-07-12T18:36:10Z |
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| fulltext |
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 47, № 3240
UDC 616–71
V. AZIMIRAD,1 M. HOSSEINPOUR,1 P. SHAHABI,2 M. ALIMOHAMMADI,1
M. SADIGHI,2 and H. HATAMI3
EFFECTS OF INJECTION OF CARBON NANOTUBES ON EEG AND RESULTS
OF A BEHAVIORAL TEST IN RATS
Received January 17, 2014
We examined the biocompatibility of carbon nanotubes (CNTs) injected i.p. into rats (1 mg/kg
body mass) by recording EEG from the frontal and occipital cortex and performing the
water maze router test before and after such injection. For EEG, the energy and average
power spectral density of wavelet coefficients in the β, α, and θ bands were considered the
features. In the water maze router experiment, the distance, time, and speed of rats were
investigated as behavioral factors. Comparison of EEG signals before and after injection
showed that introduction of CNTs exerted no significant effect on electrophysiological brain
indices. A comparison of behavioral factors before and after injection, however, showed that
injections of CNTs increased the pacing distance and time to find the desired platform and
decreased somewhat the speed in the water maze router experiment. A possible reason of this
phenomenon is the possible influence of CNTs on ion fluxes in brain neurons.
Keywords: carbon nanotubes, EEG, wavelet, water maze router, spatial memory.
1 Department of Mechanotronics, School of Engineering Emerging Techno
logies, University of Tabriz, Tabriz, Iran.
2 Neuroscience Research Centre, Tabriz University of Medical Sciences,
Tabriz, Iran.
3 Department of Biology, Faculty of Science, University of Tabriz, Tabriz,
Iran.
Correspondence should be addressed to V. Azimirad
(email: azimirad@tabrizu.ac.ir).
INTRODUCTION
Nanotechnology is an emerging field; in particular,
applications of precisely engineered nanomaterials
in neuroscience have been proposed [1�. Regarding
the properties of these tissues, a neural interface with
nanoscale components is more suitable than that with
microscale devices [2�. Carbon nanotubes (CNTs) are
an important class of synthetic nanomaterials; they
occupy a pioneering position in nanotechnology due
to their unique electrical, mechanical, thermal, and
chemical characteristics.
Hence, these mater ia ls are promis ing in
different areas of nanomedicine and, especially, of
nanoneuroscience [1, 3�. Their distinct architecture
allows these objects to effectively penetrate biological
barriers [4�. Having special physicochemical
properties, CNTs are useful for nanomedicine
applications; in particular, they improve the
performance of drug molecules as target delivery
carriers [5�. Although it has been stated that the
welldispersed CNTs have better biocompatibility
in comparison with agglomerated forms [6, 7�, the
biocompatibility of these materials has not been fully
demonstrated. However, the capabilities of CNTs
as substrates for neuronal growth, integration with
neurons, and enhancing neuronal functions are being
explored [810�. The high electrical conductivity and
excellent mechanical properties of CNTs make them
a desirable material for neuroprosthetic devices [3�.
Some other substantial properties are the dispersibility
of CNTs in physiological solvents, large surface area,
and capability of being functionalized with drugs
or imaging agents [1�. The emergence of CNTs as a
delivery vector for the CNS is based on their structural
properties. The effectiveness of CNTs in recording
neuronal electrical events has been demonstrated
[11�. Another application of CNTs is intracellular and
extracellular recording by using CNT probes [12�.
Despite an explosion of research into applications,
there is little information on the biocompatibility of
CNTs.
Cohesive properties of CNTs stably occurring in
the body are considered a possible factor for toxic
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2015.—T. 47, № 3 241
EFFECTS OF INJECTION OF CARBON NANOTUBES ON EEG
influences. Another factor that may compromise the
biocompatibility of CNTs is the dispersibility status
and the type of surface functionalization of these
materials [13, 14�. Generally, simply dispersed CNTs
are more toxic than the covalently modified ones; in
particular, pristine multiwalled carbon nanotubes
(MWCNTs) dispersed by serum were found to be more
toxic than aminoMWCNTs [15�. It has been stated that
in rats CNTs cause inflammatory responses and the
formation of lesions known as granulomas [16�. The
toxicity investigation of MWCNTs in humans showed
that CNTs may cause inflammatory and fibrotic
reactions, protein exudation, and granulomas on the
peritoneal side of the diaphragm [17�. However, it was
reported in another study that MWCNTCOCL exerted
no observable signs of damage in the spleen [18�.
MWCNTs caused inhibition of neuronal calcium ion
channels, which is due to the yttrium traces released
from these objects [19�. Even with all previous studies
on the applications of CNTs in nanomedicine, no work
has been done on the effects of these nanotubes on
electrophysiological events in the brain and on spatial
memory.
EEG analysis has been extensively used as a tool for
diagnostic monitoring of brain injuries [20� or changes
in brain functions [21�. Hence, we investigated the
biocompatibility of MWCNTs and their effect on brain
activities through analyzing EEG signals before and
after injection of MWCNTs. Some features in the time
and frequency domains were selected in terms of the
wavelet functions. A behavioral study (water maze
router experiment) was also done before and after
injection of MWCNTs to estimate changes in spatial
memory.
METHODS
Carbon Nanotube Properties. Functionalized
MWCNTs with carboxyl were used. The COOH
content of these materials was 2 wt %. They had an
inner diameter of 5 to 10 nm, an outer diameter of 10 to
20 nm, and an individual length of ~30 µm, according
to the data provided by the manufacturer. Their purity
was more than 95 wt %. The form of MWCNTs is a
black solid powder.
Animals. The experiments were carried out on six
male Wistar rats with ages varying from 4 to 6 month
and with body mass from 280 to 300 g. The animals
were kept under standard conditions (temperature
22 ± 2°C and 12 h light/dark cycle with 08:00 AM
lights on); food and water were freely available
throughout the study.
Surgical Procedure. Rats were anaesthetized
with ketamine and xylazine (i.p., 80 and 5 mg/kg,
respectively). Using a stereotaxic instrument, all
animals were implanted with two cortical stainless
steel electrodes in the frontal and occipital cortex for
EEG recording. Electrodes were fixed in the socket by
means of their pins, and the socket was fixed to the
skull by dental cement.
EEG Recording and Injection. After 3daylong
recovery from surgery, the animals were settled in a
Faraday cage, and EEG signals were recorded in a
freely moving way using light flexible conductors.
EEG signals were recorded 1 h before and 1 h after
nanotube injection. One mg/kg body mass of MWCNT
corresponding to 0.3 mg/rat was i.p. injected. A sodium
chloride solvent was used for MWCNT suspension
preparing. The MWCNT concentration in the
suspension was 0.5 mg/ml. It was taken into account
that CNTs have no difficulty in crossing the blood
brain barrier [1, 22�. After control 1hlong recording
and CNT injection, EEG signals were recorded for 1 h
30 min after the above injection.
EEG Processing . Notch and lowpass filters
were used for removing noise; the lowpass
cutoff frequency was set to 32 Hz. According
to the statements of the international 1020
system, the amplitude of EEG signals from the
scalp is 0.1 to 200 µV, and the frequency range
is 0.5 to 50 Hz. The borders of EEG frequency
components were the following: δ, 0.5–3.5 Hz;
θ, 4–7 Hz; α, 8–13 Hz; β, 14–30 Hz, and γ, > 31 Hz.
The energy and average power spectrum density (PSD)
of the wavelet coefficients were used for feature
extraction [23�.
The energy of the signal (f (t)) is as follows:
(1)
Wavelet Packet Decomposition. Feature extraction
methods for EEG analysis mainly include the following
methods: (1) fast Fourier transform (FFT): The main
disadvantage of this method was that it only uses
the frequency information and does not use the time
domain information. (2) Autoregressive (AR) model.
From the AR spectrum, the power was calculated in
multifrequency bands, and the overall power was used
as an independent variable. In addition, the AR model
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 47, № 3242
V. AZIMIRAD, M. HOSSEINPOUR, P. SHAHABI et al.
coefficients or multivariate autoregressive (MVAR)
model coefficients were used as features. (3) Time–
frequency (TF) analysis. (4) Utilizing coefficients
of wavelet transform, i.e., extracting coefficients
of wavelet transform at the useful frequency bands
according to transcendent information [24�.
The discrete wavelet transforms decompose the
signal into approximate and detailed information. The
core process is filtering; x(n) was filtered by low
pass coefficients, h(n), and highpass coefficients,
g(n), respectively. In each level, the downsampled
outputs of the highpass and lowpass filters provided
the detail Di and approximation Ai, respectively. The
first approximation was further decomposed, and the
process was continued until the desired result was
obtained. Hence, the Daubechies mother wavelet of
order 4 was used, and EEG signals were decomposed
into three levels on the wavelet basis (Fig. 1).
There were three levels, 48, 816, and 1632 Hz,
which are similar to the θ, α, and β ranges. The power
spectral density for these coefficients was calculated
as the feature, and the wavelet coefficients are shown
in Fig. 2 AC.
Spectral Estimation Method. Spectral density
methods extracted information from a signal to
describe the distribution of its power in the frequency
domain. The PSD was defined as the Fourier transform
of the autocorrelation function [25�. Here, the Welch’s
method was applied for estimating the PSD. It
divided timeseries data into overlapping segments by
computing a modified periodogram of each segment.
A hamming window with 64 lengths was selected, and
then the PSD estimates were averaged.
Water Maze Router Experiment. The water maze
router experiment was used for investigating the
behavioral effect of MWCNTs on the learning ability
and spatial memory of rats. The animals were put into
a circular tank filled with water, and they swam to
find a hidden platform below the water (22 to 32°C)
surface. The experiment was done in a semidark space
and a black tank with a black platform; therefore, the
rats were able to minimally use their visual system for
identifying and finding the platform. Three factors, the
distance, time, and speed of rats to find the platform,
were set as variables. The training duration was
considered to be 5 days, and four trials were done
every day. Finally, the values of variables in injected
rats were compared with the values of corresponding
variables in the control (before injection).
Statistical Analysis . Statistical analysis was
performed using SPSS. The pairedsample ttest was
done on results of the time and frequency domains.
The P significance values were set at 0.05.
RESULTS
EEG Signal Analyses. Results of EEG signal analysis
are presented in Table 1. It summarizes the results
of average PSD of wavelet coefficients (β, α, and θ)
and energy before (control group) and after injection
(injection group) of MWCNTs.
As shown in Table 1 and Fig. 2, the average PSD and
overall energy values before injection were, in general,
F i g. 1. Scheme of the analysis of EEG
recods.
Р и с. 1. Схема аналізу записів ЕЕГ.
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2015.—T. 47, № 3 243
EFFECTS OF INJECTION OF CARBON NANOTUBES ON EEG
higher than their corresponding values after injection, but
these differences did not reach the significance level (P >
> 0.05 for all of them). Hence, injected CNTs exerted no
significant effect on the brain functions, and it could be
concluded that these materials are biocompatible with
the CNS. On the other hand, the obtained subsequence
from the behavioral study was different.
Results of the Water Maze Router Experiment.
As was mentioned, the time, distance and speed factors
were calculated in this experiment for two groups of
rats including the control (before injection) and post
injection (after to injection). Results of the experiment
are presented in Table 2. It summarizes values of the
means, standard deviations, and Pvalues for the time,
distance, and speed factors.
According to Table 2, the Pvalues for the distance
and speed factors were lower than 0.05. Therefore, the
differences between results were significant. For the
time factor, the Pvalue was 0.07. This value was more
than 0.05, but it was considered close to significant
(Pvalues changed from 0.05 to 0.10). The results for
the time factor in two groups of rats including the
control group and the CNTinjected group are shown
in Fig. 2.
As Fig. 3A shows, the time factor in the injection
group was higher than that in the control group. The
results for the distance factor are shown in Fig 3B.
According to this panel, the distance factor of the
injection group was greater than that in the control
group. The results for the speed factor in the two
groups are shown in Fig. 3C. This panel demonstrates
that the speed factor in the injection group was higher
than the control group. As was mentioned above,
according to the results of CNT injection into the rats’
body, CNTs exerted no significant effect (Pvalue
>0.05) on EEG signals. The results of the water maze
router experiment, however, showed that CNTs had a
negative effect on spatial memory, and their injection
increased the time and distance factors and decreased
the speed factor.
T a b l e 1. Paired-Sample Statistics for the Mean Powers of the Wavelet Coefficients and Energy Analysis of EEG
Т а б л и ц я 1. Статистика парних виборок для середніх значень потужності вейвлет-коефіцієнтів та аналіз енергії для ЕЕГ
Parameter Groups Means n s.d. P values
Energy Injected
Control
0.000001
0.000002
6
6
0.4665115
0.4362918
0.102
Average power of the β band
(D1 coefficient)
Injected
Control
0.00
0.000619
6
6
0.000
0.0000882
0.500
Average power of the α band
(D2 coefficient)
Injected
Control
0.00
0.00931
6
6
0.000
0.0000252
0.743
Average power of the θ band
(D3 coefficient)
Injected
Control
0.00
0.000883
6
6
0.000
0.0001162
0.845
T a b l e 2. Paired-Sample Statistics for the Time, Distance, and Speed Factors in the Water Maze Router Test
Т а б л и ц я 2. Статистика парних виборок для факторів часу, відстані та швидкості в тесті з водним лабіринтом
Name Groups Means n s.d. P values
Distance Injected
Control
6.3543E2
2.8265E2
5
5
67.7117917
62.62852
0.00
Speed Injected
Control
49.0000
56.6500
5
5
5.3268189
5.25179
0.031
Time Injected
Control
58.2720
41.9960
5
5
3.1471845
12.47923
0.070
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 47, № 3244
V. AZIMIRAD, M. HOSSEINPOUR, P. SHAHABI et al.
–0.04
–0.05
–0.05
–0.04
–0.04
0.5
0.5
0.5
0.5
0.5
1.0
1.0
1.0
1.0
1.0
1.5
1.5
1.5
1.5
1.5
2.0
2.0
2.0
2.0
2.0
2.5
2.5
2.5
2.5
2.5
3.0
3.0
3.0
3.0
3.0
3.5
3.5
3.5
3.5
3.5
4.0
4.0
4.0
4.0
4.0
4.5
4.5
4.5
4.5
4.5
5
5
5
msec
msec
msec
msec
msec
5
5
–0.02
–0.02
–0.02
0
0
0
0
0
0
0
0
0
0
0.02
0.02
0.02
0.04
0.05
0.05
A
B
C
0.04
0.04
–0.05
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 msec5
0
0
0.05
F i g. 2. Wavelet coefficients for different levels before and after
injection of carbon nanotubes. A–C) Coefficients for the second (A,
D1), third (B, D2), and fourth (C, D3) levels.
Р и с. 2. Вейвлеткоефіцієнти для різних рівнів перед ін’єкцією
вуглецевих нанотрубок та після неї.
DISCUSSION
Carbon nanotubes have many applications in
neuroscience, e.g., in the treatment of glioblastoma
tumors [26� and neural tissue repair using neural stem
cells (NSCs) [27� The CNT films are mechanically
compatible with neural tissues and could be used as
implants or repairing devices for neurologyrelated
injuries [28�. CNTmediated therapy is a valuable
option for the treatment of neurodegenerative diseases,
including the treatment of stroke [29�. The success of
carbon nanotube applications in medicine is, however,
closely dependent on their interaction with neurons,
especially with respect to possible changes in the
neural excitability, ion conductance, and synaptic
transmission [11�. Some reports showed that the
electrophysiological properties of neurons are affected
after passage of electrical current through CNTbased
substrates [3032�. So far, only a few studies have
0
0
20
200
40
400
60
600
10
100
30
300
50
500
70
700
800
sec
cm
A
B
C
0
20
40
60
10
30
50
70
cm/sec
F i g. 3. Means of the time factor (A), distance factor (B), and speed
factor (C) before and after CNT injection.
Р и с. 3. Середні значення факторів часу (А), шляху (В) та
швидкості (С) перед ін’єкцією вуглецевих нанотрубок та після
неї.
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2015.—T. 47, № 3 245
EFFECTS OF INJECTION OF CARBON NANOTUBES ON EEG
been reported regarding the biocompatibility of CNT
within the brain tissue in vivo.
The first study using CNT for the treatment
of dissociated hippocampal neuronal cultures
demonstrated the maintenance of neuronal viability,
induction of morphological modifications in neurons,
enhancement of neurites, and outgrowth and increasing
suppression of growth cones. Furthermore, it was shown
that MWCNTs may affect the Ca2+ dynamics in neurons
(reduction of depolarizationdependent influx of Ca2+)
[33�. Investigation of internalization and toxicity of
MWCNTs and their effects on microglia cells showed
that these objects are uptaken by microglia cells without
manifestations of toxicity. According to these results,
no changes in cell proliferation were observed in the
presence of CNTs [34�.
Investigations with CNTs dispersed in various
surfactants showed that their cytotoxicity depends
on the surfactant type. For example, sodium docecyl
benzene sulfonate (SDBS) led to noticeable toxicity,
while sodium cholate (SC) did not induce the latter
[35, 36�. Investigation of the effect of MWCNTs
on potassium (K+) channels showed that the
activity of these channels was suppressed [37�. In
general, comparison of studies on the toxicity and
biocompatibility of CNTs is difficult; however, it can
be concluded that promising results were obtained in
the studies where chemically functionalized CNTs
were used [1�.
According to the obtained results, CNTs showed
a high biocompatibility with different cell types
and no negative effects on neuronal morphology,
cell viability, and basic cellular functions [38�. The
in vivo investigation of results of introduction of
MWCNTs revealed that they are biocompatible, and
no damage at the cellular structural level has been
observed until now [39�. At the same time, CNTs
can block the channel pores and interrupt the ion
permeability. Similarly, they caused a significant
impairment of the cytoplasmic Ca2+ elevation when
neurons were depolarized. This effect may be due to
the CNT interference with the functioning of Ca2+
channels [40�. According to one of the previous
works, injection of MWCNT can lead to a transient
and selflimiting local inflammatory response [41�.
The negative effect of CNTs on spatial memory
was, presumably, due to a disorder of ions in the
functioning of some channels and blocking of ion
fluxes. The main probable factor in this phenomenon
was suppression of potassium channels by MWCNTs.
This may cause changes in the resting and action
potentials and, therefore, affect the conduction of
some signals related to spatial memory.
The study was carried out in accordance with the statements
of the Council Directive regarding the protection of animals
used for experimental and other scientific purposes (86/609/
EEC, 1986, Strasbourg) and respective regulations of the Ethics
Committee at the Tabriz University of Medical Sciences, Tabriz,
Iran.
The authors of this study, V. Azimirad, M. Hosseinpour,
P. Shahabi, M. Alimohammadi, M. Sadighi, and H. Hatami,
confirm that the research and publication of the results were not
associated with any conflicts regarding commercial or financial
relations, relations with organizations and/or individuals who
may have been related to the study, and interrelations of co
authors of the article.
В. Азімірад1, M. Хоссейнпур1, П. Шахабі2,
М. Алімохаммаді1, М. Садігхі2, Х. Хатамі3
ВПЛИВИ ІН’ЄКУВАННЯ ВУГЛЕЦЕВИХ НАНОТРУБОК
НА ЕЕГ ТА РЕЗУЛЬТАТИ ПОВЕДІНКОВОГО ТЕСТУ У
ЩУРІВ
1 Школа прогресивних інженерних технологій Табризь
ського університету (Іран).
2 Центр нейронаукових досліджень Табризьського
університету медичних наук (Іран).
3 Табризьський університет (Іран).
Р е з ю м е
Ми досліджували біосумісність вуглецевих нанотрубок
(ВНТ), ін’єкованих щурам (1 мг/кг маси тіла, внутрішньо
очеревинно), відводячи ЕЕГ та застосовуючи поведінковий
тест із водним лабіринтом перед такою ін’єкцією та після
неї. Параметрами ЕЕГ вважали енергію та усереднені щіль
ності спектральної потужності вейвлеткоефіцієнтів для
бета, тета та альфаритмів. В експерименті з водним ла
біринтом поведінковими факторами були відстань, час та
швидкість руху щурів у пошуках цільової платформи. По
рівняння сигналів ЕЕГ перед ін’єкцією ВНТ та після неї
показало, що введення нанотрубок істотно не впливало на
електрофізіологічні показники мозку. Порівняння ж пове
дінкових показників перед ін’єкцією та після неї, проте, за
свідчило, що введення ВНТ викликало вірогідне збільшення
шляху до платформи і тривалості її пошуків, а також де
яке зменшення швидкості пересування у водному лабірин
ті. Можливою причиною такого феномену є вплив ВНТ на
іонні токи в нейронах мозку.
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 47, № 3246
V. AZIMIRAD, M. HOSSEINPOUR, P. SHAHABI et al.
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