Involvement of angiotensin II and angiotensin IV in producing the individual characteristics of defensive and feeding behavior in rats

The involvement of angiotensin II and angiotensin IV in defensive (the tail-flick test) and acquired feeding behavior in rats was studied. Angiotensin II had a greater role than angiotensin IV in feeding behavior in rats. Angiotensin IV had a greater effect than angiotensin II on the defensive behavior of individuals. Individual differences in animal behavior were identified.     

Expression of the startle reaction in rats genetically predisposed towards different types of defensive behavior

The magnitudes of startle reactions, consisting of shuddering in response to acoustic signals, were studied in rats selected for predisposition to different types of defensive behavior—rats with and without passive defensive freezing reactions (catalepsy), and Norway rats selected for a lack of defensive aggression to humans or for high levels of aggression; studies were performed in an SR-Pilot apparatus. These experiments showed that expression of the startle reaction to standard sound signal in rats with a genetic predisposition to catalepsy was double that in control Wistar rats. A similar but greater difference was seen between highly aggressive and non-aggressive rats: the amplitude of the startle reaction in rats with high levels of active defenside responses was three times that in rats showing no aggression towards humans. Extinction of the reflex reaction was significantly slower in highly aggressive rats than in non-aggressive rats. A similar tendency was seen in rats with genetic predisposition to the passive defensive freezing reaction as compared with Wistar rats. It was concluded that animals with an inherited tendency to defensive behavior have higher levels of the emotional fear state, regardless of the strategy of the defensive behavior. Translated from Rossiiskii Fiziologischeskii Zhurnal imeni I. M. Sechenova, Vol. 85, No. 1, pp. 99–104, January, 1999.     

Role of the striatum in the mechanism of serotoninergic effects on the course of metrazol convulsions in rats

The effect of 5-hydroxytryptophan (5-HT) and parachlorophenylalanine (PCPA) on behavioral and electroencephalographic manifestations of metrazol convulsions during electrical stimulation and destruction of the striatum was studied in freely moving rats. The effect of the compounds on the seizures, the myoclonic spasms, and the spike-and-wave activity evoked by metrazol did not depend significantly on the functional state of the corpus striatum. Meanwhile the ability of 5-HT to ameliorate, and of PCPA to aggravate the course of the generalized convulsion and the postconvulsive state was potentiated by stimulation and abolished by destruction of the striatum. It is suggested that activation of the serotoninergic mechanisms may be responsible for the abolition of the convulsions that is observed in the case of excitation of the corpus striatum.Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 7, pp. 789–792, July, 1976.     

Effect of brain extracts from rats subjected to metrazol kindling on generalized epileptic activity

Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Department of Pathophysiology, N. I. Pirogov Odessa Medical Institute. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 3, pp. 271–274, March, 1989.     

Qualitative and quantitative changes in the brain phospholipid spectrum of rats with metrazol seizures

Kh. Abovyan Armenian Pedagogic Institute. Institute of Experimental Biology, Academy of Sciences of the Armenian SSR, Erevan. (Presented by Academician of the Academy of Medical Sciences of the USSR A. N. Klimov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 1, pp. 7–9, January, 1991.     

Influences of an acoustic signal with ultrasound components on the acquisition of a defensive conditioned reflex in Wistar rats

The effects of short (90 sec) exposures to a complex acoustic signal with ultrasound components on the acquisition of a defensive conditioned two-way avoidance reflex using an electric shock as the unconditioned stimulus in a shuttle box were studied in female Wistar rats. This stimulus induced audiogenic convulsions of different severities in 59% of the animals. A scale for assessing the ability of rats to acquire the conditioned two-way avoidance reflex was developed. Presentation of the complex acoustic signal was found to be a powerful stressor for Wistar rats, preventing the acquisition of the reflex in the early stages (four and six days) after presentation. This effect was independent of the presence and severity of audiogenic convulsions in the rats during presentation of the acoustic signal. On repeat training nine days after the acoustic signal (with the first session after four days), acquisition of the reflex was hindered (as compared with controls not presented with the acoustic signal). However, on repeat training at later time points (1.5 months after the complex acoustic signal, with the first session after six days), the rats rapidly achieved the learning criterion (10 correct avoidance responses in a row). On the other hand, if the acoustic signal was presented at different times (immediately or at three or 45 days) after the first training session, the animals’ ability to acquire the reflex on repeat training was not impaired at either the early or late periods after exposure to the stressor. These results suggest that the complex acoustic signal impairs short-term memory (the process of acquisition of the conditioned two-way avoidance reflex at the early post-presentation time point) but has no effect on long-term memory or consolidation of the memory trace. __________ Translated from Zhurnal Vysshei Nervnoi Deyatel’nosti imeni I. P. Pavlova, Vol. 56, No. 3, pp. 371–378, May–June, 2006.     

Emotional behavioral disorders in rats following injection of subconvulsant doses of metrazol

Laboratory of General Pathology of the Nervous System, Research Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 2, pp. 123–126, February, 1991.     

Typological features in the behavior of rats

The existence of internal relationships between measures of investigative and seeking types of activity and the level of anxiety was demonstrated in rats. Individual measures of investigative activity and levels of anxiety were measured using classical methods-the open field test and the elevated plus maze test. The productivity of directed seeking activity was studied using methods developed by ourselves in a universal problem-solving box. Cluster analysis demonstrated hierarchical groups in the population with similar quantitative-qualitative behavioral characteristics.     

Effect of whisker removal on defensive behavior in rats during early ontogenesis

The effects of restriction of sensory afferentation in rats by vibrissectomy performed daily on days 9 to 20 of life on the formation of defensive reactions in early postnatal ontogenesis were studied. Vibrissectomized and control rat pups were assessed in terms of the extent of motor defensive reactions in response to touching the skin from days 10 to 18 of life, the duration of the freezing reaction at age 20 days, and behavior in the open field at age 25 days. Vibrissectomized rat pups showed the following significant differences from controls: a decrease in the extent of early withdrawal from a potentially dangerous stimulus (at age 12 and 13 days), a decrease in the duration of the freezing reaction, and decreases in that extents of the flight reaction and emotional reactivity in the open field test. __________ Translated from Zhurnal Vysshei Nervnoi Deyatel’nosti imeni I. P. Pavlova, Vol. 55, No. 5, pp. 677–683, September–October, 2005.     

Effect of metrazol on time course of membrane-bound calcium level in the cerebral cortex

I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR. S. M. Kirov Military Medical Academy, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR N. G. Ivanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, pp. 50–51, January, 1989.     

Potentiation of changes in brain electrical activity in A constant magnetic field by means of metrazol

The effect of metrazol on changes in spontaneous and evoked electrical activity of the cerebral cortex, hypothalamus, and cerebellar cortex in a constant magnetic field (CMF) of intensity 500, 1000, and 4000 Oe was studied in experiments on rats. After preliminary injection of metrazol in a subconvulsant dose, the spontaneous rhythmic activity of the rats changes more sharply, the amplitude of the evoked potential increases considerably, and the number of additional phases in its structure rises. Potentiation of the effect of CMP by the analeptic action of metrazol points to the essential importance of the level of activation of the CNS in the response to the action of a magnetic field.(Presented by Academician of the Academy of Medical Sciences of the USSR. P. D. Gorizontov.) Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 87, No. 1, pp. 21–24, January, 1979.     

Effect of septal lesions on conditioned defensive burying

Every control rat shocked by a wire-wrapped prod mounted on the wall of a test chamber buried the prod with bedding material from the floor of the chamber. Although this conditioned defensive burying was also observed in every rat with a lesion of the anterior septum (Experiment 2), no rat with a lesion of the entire septum (Experiment 1) or a lesion limited to the posterior septum (Experiment 2) was observed to engage in this behavior. These results confirm previous reports of the involvement of the septal area in defensive behavior and provide the first demonstration of the utility of the conditioned defensive burying paradigm in assessing the behavioral effects of limbic lesions.