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K Treptow

Publications and source records attributed to K Treptow.

At least 19 recordsLinked to original sources
PubMed1986

[The effect of substance P on the swimming behavior of rats under stressing and nonstressing conditions].

Experiments of acute and chronic stressing were investigated in rats. The behavioural features were analyzed. The acute stressing situation involves a swimming test from which rats can escape by entering a little platform. Repeated experiments every 10 min cause an exponential decreased reaction response. 250 micrograms/kg substance P i.p. accelerate the learning reactions. Chronic stress situation was managed by immobilization of several hours daily in a period of 11 d. Neurotic behavioural features were observed after application of 250 micrograms/kg substance P i.p., such as twitch of ears and head, "wet dog" shakes and increased grooming. In open field there were decreased locomotor and exploratory reactions after injection of 250 micrograms/kg substance P i.p. In an added acute stress exposition behavioural characteristics were improved after these doses of the peptide, such as unsuccessful trial to jump out, latency to liberate and period of no moving. The results were discussed in relation to the function of substance P as a regulatory peptide.

Animals↗
PubMed1986

The essential sequence of substance P for locomotion.

In rats the effect of substance P SP (1-11 and SP (5-11) heptapeptide on locomotion in open field was investigated after intrategmental application. SP (1-11) increase the locomotor activity significantly, SP (5-11) heptapeptide do not-do it. The effect of SP(1-11), SP(5-11) heptapeptide, SP(6-11) hexapeptide, and SP(1-4) tetrapeptide on the circadianly organized locomotor activity was researched after i.p. application at 11 a.m. (light phasis, low activity of rats) or 7 p.m. (dark phasis, high activity). An increased effect on locomotiou'slow activity of rats appears by SP(1-11) and SP(1-4) tetrapeptide application for several hours in light time. Both peptides display a decreasing effect on locomotion after application for several hours in dark time, too. SP(5-11) heptapeptide and SP(6-11) hexapeptide do not have any influence on locomotion. The effects of SP(1-11) are equal to results found after application into the ventral tegmental area. The experimental results display that SP acts as a regulatory peptide modulating the activity of rats by a levelling mechanism. The N-terminal SP-sequence, SP(1-4), acts in a similar manner. The effects are discussed in relation to the mediation by receptors which recognize the C- or N-terminal part of the SP molecule.

Amino Acid Sequence↗
PubMed1985

[Effect of desaminoocta-pancreozymin on the locomotor activity of rats].

The influence of desaminoocta-pancreozymin (DAO-PZ) was investigated in high and low activity periods by intraperitoneal or intranasal application. DAO-PZ is a CCK-8 derivative in which the N-terminal amino acid (Asp) is exchanged for succinyl acid. A decreasing long lasting effect for 3 to 4 h was always observed in locomotor activity. A food reduction was also proved after i. p. and intranasal application. The effects correspond to those of CCK-8 reported in the literature. They are discussed in this respect.

Animals↗
PubMed1983

Modulation of locomotor activity by substance P in rats.

The effects of intraperitoneally or intracerebrally (DA A-10 area) administered substance P (SP) on locomotor activity of rats were studied in an exact 12-h light/12-h dark cycle changing from dark to light at 6 a.m. SP was administered either at 11 a.m. (light phase, minimal locomotor activity) or at 7 p.m. (dark phase, maximal locomotor activity). The effects of 12.5 micrograms/kg SP intracerebral and 125 micrograms/kg SP intraperitoneal were very similar. In the light phase SP produces excitation but inhibition of locomotion in darkness. Hence, the effect of SP depends on the internal mechanisms controlling motor activity and tends to level off the spontaneous circadian oscillation. We found a long lasting SP effect during both the light and dark period. The present experiments led us to the conclusion that SP has a levelling effect on locomotor activity. Probably this effect might be explained as SP's action on the dopaminergic pathway or dopamine metabolism, because the dopamine content in neurons also has a circadian rhythm.

Animals↗
PubMed1976

[Dynamics of adaptation and maladaptation phenomena in rats exposed to weak chronic stimulation].

Experiments were carried out with rats to study the influence of disturbing artifical light-dark regimens. The findings are consistent with the definition of "relatively weak stress-stimuli" which, according to R. BAUMANN, can be essential in causing regulation diseases. Disturbances in the circadian patterns of spontaneous motor activity are described as an inversion of normal activity maxima and minima, as periodicity step-down and as a dissolution of the day-periodical order. Their occurrence is proportional to the magnitude of the disturbing effect. As vegetative disturbing effects there occurred transient hypertensive derangements, the extent of which is inversely proportional to the magnitude of the stressing stimulus. These differences are discussed basing on a hypothesis of differently synthetized cerebro-visceral regulation mechanisms.

Animals↗
PubMed1976

[Diurnal dynamics of periodicities in conditional-reflex processes in the minute range].

Male adult albino rats living from the 6th week of their lives under conditions of artificial light-dark cycle (16 hrs light, 8 hrs dark) were used to study possible relationships between circadian sensitivity cycles and synchronization of dynamics and the frequency variability of periodicities of reaction times of conditional-reflectory processes with wavelengths in the minute range. The experiments have revealed differences at the time of the activity maximum and minimum of a circadian cycle in the studied parameters of the minute rhythm (mean level of oscillation, mean amplitude, length of period and coupling). In the dark phase (activity maximum) there prevailed an increased level of central-nervous excitation and a tendency towards a higher frequency and diminished coupling of minute periods. In the light phase (activity minumum) the animals showed a balanced level of excitation, reduced frequency and a rigid coupling of periodicities of conditional-reflectory events involved in the process. Relations are shown to exist between central-nervous processes and circadian sensitivity cycles. For the experimental practice it is concluded that the different times of the day should be accounted for in assessing the criteria of minute rhythm and in conditional-reflectory studies in pharmacology and toxicology.

Animals↗
PubMed1976

[The role of uncertainty in the conditioned-reflex learning behavior for selected cardiovascular functions].

As a contribution to quantitative analysis of exogenous stress action, the role of probability learning (probability stress, probability affirmation) for selected cardio-vascular functions was studied in 25 albino rats and 8 dogs. It has been shown in the rats learning with probability stress that a dependence exists between stress probability, on the one hand, and conditional-reflectory processes and systolic blood pressure rise, on the other, that is, the pathogenic action of probability stress increases from a probability of p = 1.0 to p = 0.5. An analogous picture was found with the probability affirmation being applied in dogs. While a probability affirmation with p = 1.0 promoted adaptational processes, a value of p = 0.5 led to experimental neurosis, tachycardia and ECG alterations. The results obtained are discussed in context with the information entropy and information theory of emotions.

Animals↗
PubMed1976

[The effect of lesions of the caudate nucleus on the development of hypertonic blood pressure dysregulation due to learning stress].

Male albino rats were used to study the effect of excluding the nucleus caudatus upon the development of a hypertensive dysregulation induced by the load of learning (stress). A 3-week stress exposure considerably restricted learning and memory processes in all the animals with nucleus caudatus lesions. Systolic blood pressure values and adrenal weights were within the physiological range. In animals with intact brains, the same stress exposure caused a certain restriction of learning processes and a rise of blood pressure and adrenal weight. The results described here show that the lesions of nucleus caudatus structures, similar to the exclusion of circumscribed areas of the hippocampus and the reticular formation, prevents spreading of stress-induced emotional excitation into visceral functional areas.

Animals↗
PubMed1975

[Biphasic effect of angiotensin II on conditioned reflectory reaction patterns in albino rats].

40 male albino rats were used to investigate the influence of one single i. v. dose of 10 ng/kg Angiotensin II upon established and stabilized conditional-reflectory response pattern (two-dimensional conditional-reflectory decision process and periodicities of conditional-reflectory processes). At normotonous blood-pressure values, Angiotensin II exerted a biphasic action on the conditional-reflectory response pattern. In the first phase of action (up to 30 min after injection) there prevailed centralnervous inhibition processes, while the second phase of action (30-70 min after injection) was marked by a general centralnervous excitation, which is reflected by extremely short times of response, and a pronounced sensitivity to optic, acoustic and tactile stimuli. The decision capacity of the animals was considerably reduced in both phases. The periodicities of conditional-reflectory processes (duration of periods in the minute range) are strongly disturbed in the first phase of action, and tend to normal in the second phase. Furthermore, Angiotensin II was found to have a selective, hierarchically ordered influence with regard to the duration and intensity of action. Thus, the information processing activity of the CNS underwent most pronounced changes. The centralnervous regulatory functions were less affected; the blood pressure regulation showed little and transient influence by Angiotensin II. In the discussion, the neurotropic and algogenic action of Angiotensin II, and the relation of the octapeptide effect with pathogenetic mechanisms of experimental neurotically induced hypertonia are dealt with.

Angiotensin II↗
PubMed1975

[Effect of angiotensin II on the conditional relfex response patterns of neurotic albino rats].

The effect of one single dose of 10 ng Angiotensin II/kg body weight upon affirmed conditional-reflectory response patterns (two-dimensional conditional-reflectory decision process and periodicities of conditional-reflectory processes) was studied in 50 male albino rats in which a neutrotically induced hypertensive blood pressure regulation had been elicited by stress exposure for 135 days. Contrary to healthy animals in which Angiotensin II was demonstrated to act in a biphasic manner, the neurotic animals revealed a monophasic action manifesting itself by a generalized centralnervous excitation. It was noticed, furthermore, that the information processing and regulatory processes of the CNS are considerably disturbed. The chronically hypertensive systolic blood pressure values of neurotic animals, like in healthy ones, show a brief, transient rise immediately following administration of Angiotensin II. These results are not only another proof of a neurotropic component of Angiotensin II action, but they show also that this action allows one to judge the state of disturbed nervous functions. The correlation of the neurotropic effect of Angiotensin II with pathogenetic mechanisms of experimental neurotically induced hypertension is discussed.

Angiotensin II↗
PubMed1975

[Significance of different social factors active in the course of ontogenesis, for the effectiveness of chronic stress influences upon cerebro-visceral regulation processes of albino rats].

Fifty male albino rats were used to study how social factors (animals kept in large groups with playing-cage character, or in social isolation by solitary maintenance) are reflected in the responsiveness of cerebro-visceral regulation processes to chronic stress exposure. The following results were obtained: Animals kept from the 12.-30. week of life in social companionship and, additionally, exposed to chronic stress influences, proved to be greatly resistant to permanent load. This effect is referred to the rich supply of social afferentations and to the pronounced stimulation of proprioreceptive reafference as a result of social communication and motor activity. Animals kept, after preceding large-group maintenance, in social isolation from the 17.-30. week and simultaneously being exposed to the same stress influence as the animals in the playing cage, showed symptoms of an early stage of neurotically induced, arterial hypertension. Here, the chronic lack of socially determined, adequate environmental afferentation and of proprioreceptive reafference, as was typical of solitary maintenance, proved to be a factor enhancing the pathological predisposition of the organism under extreme environmental conditions.

Adaptation, Physiological↗