Другие статьи

Цель нашей работы - изучение аминокислотного и минерального состава травы чертополоха поникшего
2010

Слово «этика» произошло от греческого «ethos», что в переводе означает обычай, нрав. Нравы и обычаи наших предков и составляли их нравственность, общепринятые нормы поведения.
2010

Артериальная гипертензия (АГ) является важнейшей медико-социальной проблемой. У 30% взрослого населения развитых стран мира определяется повышенный уровень артериального давления (АД) и у 12-15 % - наблюдается стойкая артериальная гипертензия
2010

Целью нашего исследования явилось определение эффективности применения препарата «Гинолакт» для лечения ВД у беременных.
2010

Целью нашего исследования явилось изучение эффективности и безопасности препарата лазолван 30мг у амбулаторных больных с ХОБЛ.
2010

Деформирующий остеоартроз (ДОА) в настоящее время является наиболее распространенным дегенеративно-дистрофическим заболеванием суставов, которым страдают не менее 20% населения земного шара.
2010

Целью работы явилась оценка анальгетической эффективности препарата Кетанов (кеторолак трометамин), у хирургических больных в послеоперационном периоде и возможности уменьшения использования наркотических анальгетиков.
2010

Для более объективного подтверждения мембранно-стабилизирующего влияния карбамезапина и ламиктала нами оценивались перекисная и механическая стойкости эритроцитов у больных эпилепсией
2010

Нами было проведено клинико-нейропсихологическое обследование 250 больных с ХИСФ (работающих в фосфорном производстве Каратау-Жамбылской биогеохимической провинции)
2010


C использованием разработанных алгоритмов и моделей был произведен анализ ситуации в системе здравоохранения биогеохимической провинции. Рассчитаны интегрированные показатели здоровья
2010

Специфические особенности Каратау-Жамбылской биогеохимической провинции связаны с производством фосфорных минеральных удобрений.
2010

Combined effect of high doses of irradiation and emotional stress on reflex activity of rats

The article presents a comparative analysis of the isolated radiation exposure at a dose of 6.0 Gray (Gy) and stress factors, as well as the effects of their combined influence to the conditioned reflex activity of rats. The positive dynamics of the conditioned passive avoidance reflex (CPAR) was found in animals with combined exposure of radiation and stress, where there was a slower, in comparison with experimental rats, time spent in the safe compartment of the installation.

Relevance. The problem of studying the effects of combined exposure of ionizing radiation and emotional stress on the functional activity of the brain continues to be relevant, as among the various segments of the population of radioactively contaminated areas are found such negative neuropsychiatric disorders as increased anxiety, conflict, alienation, depression, memory loss, impaired concentration [1,2]. Together, such effects can have significant consequences and acquire social significance, affecting to the performance of the adult population of radioactively contaminated territorias [3].

In connection with the above-mentioned, the purpose of our research was to study the the conditioned-reflex activity parameters of rats in case of combined effect of high doses of gamma radiation and the stress factor in the experiment.

Materials and methods. The series of carried out researches was made on 88 white outbred rats, weighing 200-220 grams, which were subsequently divided into 4 groups: I group - intact animals (n=22); II group - rats, which were once irradiated on the day of the research on the medical linear electron accelerator Clinac 600 C at a dose of 6.0 Gray (n=22); III group - animals undergoing chronic immobilization stress (CIS), during 5 days for 4 hours (n = 22); IV group - rats, which were irradiated by external acute ionization at a dose of 6.0 Gy. in combination with the subsequent chronic immobilization stress (CIS) during 5 days for 6 hours (n=22). The animals of I group were compared group for II group of rats. Accordingly, irradiated animals (II group) served as a control for III group of rats.

The conditioned passive avoidance reflex (CPAR), which based on emotional negative reinforcement [4], was carrying out on the

Table 1 The number of rats that completely reproduced the reflex passive avoidance throughout the experiment

Study groups, n-number of rats

The number of rats that completely reproduced the passive avoidance reflex (%)/observation period

1 сут.

2 сут.

7 сут.

14 сут.

I group intact animals (n=22);

100%

100%

100%

100%

II group rats, which were once irradiated on

41%

41%

4,5%

11,8%

the day of the research on the medical linear electron accelerator Clinac 600 C at a dose of 6.0 Gray (n=22);

рк0,001

р1<0,001

р1<0,001

р1<0,001

III group animals undergoing chronic

54,5%

31,8%

27%

0%

immobilization stress (CIS), during 5 days for 4 hours (n = 22);

pK0,001

p1<0,001

p1<0,001

p1<0,001

IV group rats, which were irradiated at a

50%

18,2%

31,2%

23,5%

dose of 6.0 Gy. in combination with the

p2<0,001

p2<0,001

p2<0,001

p2<0,001

subsequent CIS

рз<0,001

рз<0,001

рз<0,001

рз<0,001

Notes:

       

p1 the significance of differences compared with group I; p2the significance of differences compared with group II; p3 the significance of differences compared with group III.

     

basis of a single electrical stimulation according to a modified method of J. Bures and O.Buresova (1963 y.). The strength of the performance skill was tested 24 hours after training [5]. The criterion for the performance of the passive avoidance reflex after application of the pain electrical-skin stimulation was the stay of animals in the light compartment of the camera 80% (144 s) or more of the total observation time (180 s) [6]. In all examinated groups, the keeping of the memory engram was studied during 14 days of the research.

The research results were processed statistically using the parametric Student's t-test using a set of standard Microsoft Excel programs [7].

Results and discussion. The results of studies are shown on Diagram 1, where it can be seen that on the first day of observation (24 hours after training) the duration of placing in

the illuminated compartment of the camera in the intact group was 177.45±1.53 seconds. The studied parameter turned out to be more than the 144-second criterion for the performance of a reflex [6]. The obtained data testified about successful performance of the conditioned passive avoidance reflex by the control animals. Further observations made possible to establish that the trained rats demonstrated indicators which exceeding the criterion of the performance of reflex on the 2nd (173.54±2.17 s), 7th (174.09±2.05 s) and 14th (176,35±1.35 s) day of the experiment. In this group, were registered the largest number of rats with a maximum residence time (180 s) in the light compartment of the camera. So, starting from the 1st day and until the end of the observation, the number of rats that fully reproduced CPAR, reached a maximum - 100% (Table 1).

JLaccuracy of differences between I and II groups;

accuracy of differences between I and III groups;

Diagram 1 The dynamics of the time spent in the light compartment of the camera in the study of the performance of passive avoidance reflex
in intact animals (group I) and experimental group rats

Analysis of the results which obtained in the II group, which undergo to a single external acute exposure at a dose of 6.0 Gy, showed that on the 1st day, as well as on the 2nd day of the study, the residence time in the light compartment of the camera decreased on average by 2 times compared with the intact group and amounted to 84.66±77.73 s (p1<0.001) and 82.85±79.92 s (p1<0.001), accordingly. In both groups, there were a low percentage of animals that fully reproduced the acquired skill (on average 41%). In the following days of the experiment was revealed a further progressive decrease in the degree of keeping of the acquired conditioned connection. So, on the 7th day of observation, the time spent in the safe compartment decreased to almost 90% in comparison with the I group of animals. Only 4.5% of the rats were able to stay in the light compartment of the experimental setup for 180 seconds. However, on the 14th day of observation, the percentage of animals that fully reproduced the reflex of passive avoidance increased 2 times (40.06±58.34; p1<0.001) compared with the previous indicator.

In animals of the third group which undergo to chronic immobilization, it was revealed that 1 week after the training procedure, the time in the light compartment of the camera was significantly less than in intact rats. In the study period, the duration of being in the illuminated part of the camera began to be 57.50±76.73 s (p2<0.001), which was on average 2.5 times less than the general criterion for the performance of reflex. No such animals were detected at all on the 14th day of observation.

In IV group rats, which exposed by the combined effects of radiation and chronic immobilization stress, signs of decrement CPAR were observed on the 2nd day of the study, when the time spent in the light part of the camera was more than 2 times

# accuracy of differences between II and IV groups

shorter and was 48.65±68.04 s At the same time, the number of animals that fully reproduced the acquired skill was the smallest (18.2%). Despite this, in the following days of observation, the dynamics of passive avoidance reaction was significantly

different from that in the II and III groups of experimental animals (diagram 2, 3): both the number of rats that completely reproduced passive avoidance reaction and time spent in the light compartment of the camera are increased.

120

Diagram 2 The dynamics of the time spent in the light compartment of the camera in the study of the performance of the passive avoidance
reflex in animals of the II and IV groups

ІП group IV group

ix>

0 ,

al day day a7 day aldday

+ accuracy of differences between III and IV groups

Diagram 3 The dynamics of the time spent in the light compartment of the camera in the case of studying the performance of the
passive avoidance reflex in animals of the III and IV groups

Conclusion. Thus, the results of the experiments showed that only in the group of animals which exposed to radiation is observed a steady decline in the residence time in the light compartment of the camera. The 14th day of the study is characterized by the shortest duration of stay of rats in a safe camera and the absence of animals that completely reproduced the acquired skill. In the II and IV groups, the dynamics of passive avoidance reaction was different: in both groups there was a sharp reduction in the time spent in the light part of the camera (in the II group on the 7th day, in the IV group on the 2nd day of observation) with following time elongation of stay in the lighted compartment of setup. Positive dynamics of passive avoidance reaction reflex was detected in animals of the fourth group, when the combined effects of radiation and stress led to a slower reduction of the time spent in a safe chamber, in comparison with the II and III groups.

 

REFERENCES

  1. Чуян Е. Н. Влияние электромагнитного излучения крайне высокой частоты на стрессорный ульцерогенез // Психофізіологічні та вісцеральні функціі в нормі та патологіі : матеріали VI Міжнародноі науковоі конференций, (Киів, 2012 г.). Киів: 2012. С. 226-232.
  2. Румянцева Г. М., Левина Т. М., Чинкина О. В., Степанов А. Л., Соколова Т. Н. Особенности психолого-психиатрических последствий радиационных аварий // Экология человека. 2007. №9. С. 42-47.
  3. Bing Wang, TakanoriKatsube, Nasrin Begum and Mitsuru Nenoi. Revisiting the health effects of psychological stress—its influence on susceptibility to ionizing radiation: a mini-review // Journal of Radiation Research. 2016. Vol. 57. №4.Р. 325.-335.
  4. Буреш Я.Бурешова О., Хьюстон Дж. П. Методики и основные эксперименты по изучению мозга и поведения. М.: Высшая школа, 1991. 267 с.
  5. Kokhan V.S., Afanasyeva M.A., Van'kin G.I. // Behav. Brain Res. 2012. V. 231, №1. P. 226-230.
  6. Иноземцев А.Н., Бельник А.П., Островская Р.У. Изучение условного рефлекса пассивного избегания в модифицированной трехкамерной установке // Эксп. клин. фармакол. 2007. №2. С. 67-69.
  7. Ойвин И.А. Статистическая обработка результатов экспериментальных исследований // Патологическая физиология и экспериментальная терапия. 1960. №4. С. 76-85.

Разделы знаний

International relations

International relations

Law

Philology

Philology is the study of language in oral and written historical sources; it is the intersection between textual criticism, literary criticism, history, and linguistics.[

Technical science

Technical science