Abstract
The work is focus on the analysis of data got from the scientific research. The field of Physiological psychology is very important for the nowadays science and demands great attention.
So, the research was made with help of Books, scientific journals and internet resources.
The researches of animals are very important for contemporary science. It helps much in the science researches for medicine. So that is why the aim of this research is to define the influence of caffeine on rats that would contribute much to the knowledge about caffeine and its medical effects.
It was studies the psychological function of behavior of rats and the influence of caffeine on it through 8-9 weeks from the beginning of application of caffeine. The injection of caffeine to awake rats (10 mg/kg intravenously) was accompanied by short-term decrease systolic pressure in the left ventricle and its first derivative, and also increase of frequency of reductions and minimal diastolic pressure (Lorist, 1997).
After 7-day’s injection of caffeine (on 10 mg/kg twice a day) pump function of the isolated heart did not differ from the control, but over the maximal resistance to exile created by means of overlapping outflow. Consumption of caffeine during 8-9 weeks in the form of 0,1 % of a water solution also was not accompanied by change of pump function, but the maximal intensity of the pulsate functions, defined by product of developed pressure upon frequency of reductions, has been authentically raised on 23 %. The hearts of rats consumed caffeine also were capable to support higher level of pump function at electrostimulation of auricles with the raised frequency. Calculation of factors of correlation between power and functional parameters has shown, that the most significant for is the total maintenance of myocardium (factors of correlation 0,64-0,74). Results have shown, that at long application of caffeine initial (through 1 week) decrease in developed pressure is replaced by increase through 8-9 week, and it is combined with improvement of pump function of heart at high frequency of reductions (Carlson, 2006).
Caffeine is the most widespread medicine, at least in the USA, in the form of coffee, tea, coca-colas or chocolate use it as one of kinds of stimulators of the maximum nervous activity though it acts on many other things fabrics of an organism. The mechanism of action of caffeine connects that it, as well as its basic metabolite. At studying cardiac hystiocyte caffeine in high concentration (10-20 mm) for a long time apply as means of fast liberation Ca2 + from sarcoplasmic reticulum. On rhythmically reduced objects outflow Ca2 + during between reductions reduces fraction Ca2 +, allocated of CP at regular excitation cardiac hystiocyte. In this connection on the isolated heart of a rat caffeine (0,05-0,5 mm) renders negative inotropic influence. Similar influence renders caffeine and on heart of porpoises. The raised sensitivity of a myocardium of rats caffeine is noted also at studying function isolated papillary muscles.
Daily reception of caffeine in vivo is accompanied by the natural, though also small, increase systolic increasing of blood pressure, concentration of adrenaline, fat acids in blood. However at chronic application of caffeine there is an easing of reactions and degrees of increase of a level of adrenaline in plasma. Parameters of activity of a myocardium change also, the increase in duration of complex QRS that specifies delay of conductivity in particular is noted and can (at overdose of caffeine) to serve as the reason of occurrence arrhythmic actions. In the given work we studied consequences of long application of caffeine on heart of rats and the influence of it on their behavior (Carlson, 2006).
The research was made in accordance with the following raw data.
So, it is possible to state now that the rats which were given caffeine are slower in the process of grooming, defecation; they have the lower level of motionless.
The works, devoted to studying of chronic action of caffeine on the emotional state of a person or animals, are rare, and their results are inconsistent. Thus rats get caffeine usually intra-abdominally. It was found the physiologic way, and rats or 0,1 %-s’ solution of caffeine. But they were not given anything to drink. The scientists worked with two lines of rats, one of which was more disturbing. Besides rats were differently contained: the some – in groups, and the some – one by one. The solitary confinement for these animals is the adverse factor. Uneasiness of rats define on behavior in the chamber with two branches: light and dark. The more restlessly the animal, which spend less time on light. The primary condition of nervous system of rats has not affected their bent for to caffeine – all drank approximately equally. One group of animals has tested on itself sharp influence of substance: They gave them a solution of caffeine only one day, but a doze have received very essential – in 40 times greater, than daily consumption of the adult American. However caffeine in such quantity has not rendered influence on rats which held in group. Initially disturbing rats staying in not comfortable conditions have become nervous from a shock doze, that is in single sections only. But then they have got used, but at chronic drink of caffeine have deteriorated within three weeks nerves at rather quiet rats that contained in comfortable conditions (Lorist, 1997).
From here it is possible to do a conclusion, that restless rats are firstly more sensitive to exciting action of caffeine, but at its chronic consumption get used. Quiet animals, on the contrary, short-term caffeine stress is not to cause the reaction, but in due course they start to be nervous. Scientists emphasize, that the action of caffeine depends not only on genetic features of sensitivity this substance, but also from influence of factors of an environment (in this case, from social isolation). From long consumption of caffeine the most safe were excited both in genetic, and in the social attitude of a rat. But how animals reacted to drink of a stimulant, they did not get used to it. The cancelling of caffeine has not changed their level of uneasiness (Carlson, 2006).
It is worth saying that the initially quiet rats placed in comfortable conditions and on a regular basis sipping caffeine, began to be nervous more.
Besides it became obvious that the sexual behaviour of rats depends not on influence on a brain of man’s or female hormones, and from functioning their olfactory body. Those female rats at whom “switched off” the body catching pheromones (the molecules promoting a sexual inclination), adopted sexual habits of male rats – they threw the posterity though usually spend 80 % of time in a hole. It has been noted, that female in this case behaves in accuracy as male rat. In opinion of researchers, in the brain female rat there is “a functional circuit of male behaviour”. Till now distinction of sexual behaviour at mammals was attributed to influence on a brain of female (estrogen) or male hormones, begun for embryonic stages.
Conclusion
Regular introduction of a standard doze of caffeine (40 mg/kg) to rats facilitates formation of more precise circadian rhythm of mobility. Animals with a miscellaneous Chronotype noticeably differ on sensitivity to psychostimulator. The rats initially possessing better expressed rhythmics, the amplitude of a rhythm more sharply increases, and it acrophase is more strongly displaced on early night hours. The chronotypical features of an individual are obviously important for considering in experimental and clinical psychopharmacology.
References
Carlson Neil R., (2006) Physiology of Behavior (9th Edition) (MyPsychKit Series), Allyn & Bacon; 9 edition Biochemical changes in the exocrine pancreas of rats fed caffeine.
Lorist Monicque (1997) Nicotine, Caffeine and Social Drinking: Behaviour and Brain Function, Routledge; 1 edition The hypercholesterolaemic effect of caffeine in rats fed on diets with and without supplementary cholesterol.
Weinberg Bennett Alan, Bealer Bonnie K. (2002) The World of Caffeine: The Science and Culture of the World’s Most Popular Drug, Routledge.
Weinberg Bennett Alan, Bealer Bonnie K. (2002) The Caffeine Advantage: How to Sharpen Your Mind, Improve Your Physical Performance, and Achieve Your Goals-the Healthy Way.
B. Watkinson and P. A. Fried (1985) Coffee & Caffeine During Pregnancy. Web.