scholarly journals Effect of amisulpride, olanzapine, quetiapine, and aripiprazole single administration on c-Fos expression in vasopressinergic and oxytocinergic neurons of the rat hypothalamic supraoptic nucleus

2020 ◽  
Vol 54 (2) ◽  
pp. 77-84
Author(s):  
Alexander Kiss ◽  
Jana Osacka

AbstractObjective. The goal of this study was to reveal the impact of four types of atypical antipsychotics including amisulpride (AMI), olanzapine (OLA), quetiapine (QUE), and aripiprazole (ARI), with different receptor-affinity profile and dissociation constant, on the activity of hypothalamic supraoptic nucleus (SON) vasopressinergic and oxytocinergic neurons.Methods. Male Sprague Dawley rats received a single injection of vehicle (VEH) (0.1 ml/100g), AMI (20 mg/kg), OLA (5 mg/kg), QUE (15 mg/kg/) or ARI (10 mg/kg). Ninety min after treatment, the animals were fixed by transcardial perfusion, the brains removed, and cryocut into serial coronal sections of 35 µm thickness. The sections were processed for c-Fos staining using an avidin-biotin-peroxidase complex and visualized by nickel intensified diaminobenzidine to reach black end product. Afterwards, the sections were exposed to vasopressin (AVP) and oxytocin (OXY) antibodies and the reaction product visualized by biotin-labeled fluorescent Alexa Fluor 568 dye. The data were evaluated from c-Fos and AVP or OXY merged sections.Results. The present study shows that all four antipsychotics applied induced c-Fos expression in the SON. With respect to the stimulation efficacy of the individual antipsychotics, estimated based on the quantity of c-Fos-labeled AVP and OXY neurons, could be a preferential action assigned to QUE over moderate effect of ARI and lower effect to OLA and reduced effect of AMI (VEH < AMI < OLA < ARI < QUE).Conclusion. The present data for the first time provide an insight into the quantitative pattern of brain activity within the clusters of SON AVP and OXY cells in response to different atypical antipsychotics single treatment.

2021 ◽  
Vol 12 ◽  
Author(s):  
Robert W. Seaman Jr ◽  
Gregory T. Collins

Recent estimates suggest increased popularity of the concurrent use of opioids and stimulants, with over 50% of treatment-seeking opioid users reporting regular stimulant use. The goal of the current study was to determine how opioid dependence and withdrawal affect the reinforcing effects of fentanyl, cocaine, and methamphetamine. Male Sprague-Dawley rats were allowed to self-administer fentanyl under a progressive ratio (PR) schedule of reinforcement. Baseline evaluations of reinforcing effectiveness of fentanyl, cocaine, and methamphetamine were determined. Opioid dependence was then established by administering escalating doses of morphine (10–40 mg/kg) twice-daily for four days and subsequently maintained by once-daily injections of 40 mg/kg morphine. To evaluate the impact of opioid dependence and withdrawal on the self-administration of fentanyl, cocaine, and methamphetamine, sessions occurred either 12 or 20 h after the morphine, respectively. During opioid withdrawal, the fentanyl dose-response curve was shifted rightward with an increase in maximal effectiveness, whereas it was shifted rightward with a reduction in maximal effectiveness when evaluated in rats currently dependent on opioids, relative to baseline. The reinforcing effects of cocaine and methamphetamine were unchanged by either condition. The current studies provide direct evidence that the reinforcing effects of fentanyl are increased in opioid-withdrawn rats and reduced in opioid-dependent rats, relative to rats that are not physically dependent on opioids. These findings suggest that motivations to use opioids are dependent on the state of the individual whereas stimulants retain their reinforcing effects regardless of whether the individual is in an opioid-dependent or withdrawn state.


2019 ◽  
Vol 53 (3) ◽  
pp. 165-177
Author(s):  
Alexander Kiss ◽  
Jana Osacka

AbstractObjective. The aim of the present study was to demonstrate the spatial relationship between the c-Fos immunoreactive cells elicited by an acute treatment with neuroleptics including amisulpride (AMI), olanzapine (OLA), quetiapine (QUE), and aripiprazole (ARI) and enkephalinergic (ENK), substance P (SP), and tyrosine hydroxylase (TH) innervation fields in the rat septum.Methods. Male Sprague Dawley rats received a single injection of OLA (5 mg), ARI (10 mg), AMI (20 mg), QUE (15 mg/kg/b.w.). Ninety min after antipsychotics administration, the animals were transcardially perfused with a fixative and the brains cryocut into serial coronal sections of 35 µm thickness. The sections were processed for c-Fos staining using an avidin-biotin-peroxidase complex and visualized by nickel intensified diaminobenzidine to reach black endproduct. Afterwards, the sections were exposed to ENK, SP, and TH antibodies and the reaction product visualized by biotin-labeled fluorescent AlexaFluor 564 dye. The data were evaluated from the sections either simultaneously illuminated with fluorescent and transmission microscope beams or after merging the separately illuminated sections in the Adobe Photoshop 7.0 software.Results. ENK, SP, and TH displayed characteristic spatial images formed by a dense accumulation of immunoreactive fibers and terminals on the both sides of the septum. A dense plexus of axons formed by ENK and SP immunopositive terminals were situated predominantly in the lateral, while TH ones more medial portion of the septum. QUE and AMI activated distinct amount of c-Fos expression in cells located within the SP-immunoreactive principal innervation field. The OLA effect on the c-Fos expression was very pronounced in the ventral TH-labeled principal innervation field including the space between the ENK field ventral portion and the dorsal margin of the accumbens nucleus shell. Generally, the occurrence of c-Fos cells in the ENK-immunoreactive principal innervation field, in comparison with the surrounding septal area, was less abundant after all of the four antipsychotics treatments.Conclusion. The data of the present study indicate that ENK, SP, and TH innervation fields may influence separate populations of septal cells activated by AMI, OLA, QUE, and ARI and that each of these region-differently innervated cells may be associated with the functional heterogeneity of the individual lateral septal nuclei.


2021 ◽  
Vol 15 ◽  
Author(s):  
Johanna Norrlid ◽  
Jonas M. D. Enander ◽  
Hannes Mogensen ◽  
Henrik Jörntell

The brain has a never-ending internal activity, whose spatiotemporal evolution interacts with external inputs to constrain their impact on brain activity and thereby how we perceive them. We used reproducible touch-related spatiotemporal sensory inputs and recorded intracellularly from rat (Sprague-Dawley, male) neocortical neurons to characterize this interaction. The synaptic responses, or the summed input of the networks connected to the neuron, varied greatly to repeated presentations of the same tactile input pattern delivered to the tip of digit 2. Surprisingly, however, these responses tended to sort into a set of specific time-evolving response types, unique for each neuron. Further, using a set of eight such tactile input patterns, we found each neuron to exhibit a set of specific response types for each input provided. Response types were not determined by the global cortical state, but instead likely depended on the time-varying state of the specific subnetworks connected to each neuron. The fact that some types of responses recurred indicates that the cortical network had a non-continuous landscape of solutions for these tactile inputs. Therefore, our data suggest that sensory inputs combine with the internal dynamics of the brain networks, thereby causing them to fall into one of the multiple possible perceptual attractor states. The neuron-specific instantiations of response types we observed suggest that the subnetworks connected to each neuron represent different components of those attractor states. Our results indicate that the impact of cortical internal states on external inputs is substantially more richly resolvable than previously shown.


Author(s):  
Brynne D. Ovalle ◽  
Rahul Chakraborty

This article has two purposes: (a) to examine the relationship between intercultural power relations and the widespread practice of accent discrimination and (b) to underscore the ramifications of accent discrimination both for the individual and for global society as a whole. First, authors review social theory regarding language and group identity construction, and then go on to integrate more current studies linking accent bias to sociocultural variables. Authors discuss three examples of intercultural accent discrimination in order to illustrate how this link manifests itself in the broader context of international relations (i.e., how accent discrimination is generated in situations of unequal power) and, using a review of current research, assess the consequences of accent discrimination for the individual. Finally, the article highlights the impact that linguistic discrimination is having on linguistic diversity globally, partially using data from the United Nations Educational, Scientific and Cultural Organization (UNESCO) and partially by offering a potential context for interpreting the emergence of practices that seek to reduce or modify speaker accents.


Crisis ◽  
2016 ◽  
Vol 37 (4) ◽  
pp. 265-270 ◽  
Author(s):  
Meshan Lehmann ◽  
Matthew R. Hilimire ◽  
Lawrence H. Yang ◽  
Bruce G. Link ◽  
Jordan E. DeVylder

Abstract. Background: Self-esteem is a major contributor to risk for repeated suicide attempts. Prior research has shown that awareness of stigma is associated with reduced self-esteem among people with mental illness. No prior studies have examined the association between self-esteem and stereotype awareness among individuals with past suicide attempts. Aims: To understand the relationship between stereotype awareness and self-esteem among young adults who have and have not attempted suicide. Method: Computerized surveys were administered to college students (N = 637). Linear regression analyses were used to test associations between self-esteem and stereotype awareness, attempt history, and their interaction. Results: There was a significant stereotype awareness by attempt interaction (β = –.74, p = .006) in the regression analysis. The interaction was explained by a stronger negative association between stereotype awareness and self-esteem among individuals with past suicide attempts (β = –.50, p = .013) compared with those without attempts (β = –.09, p = .037). Conclusion: Stigma is associated with lower self-esteem within this high-functioning sample of young adults with histories of suicide attempts. Alleviating the impact of stigma at the individual (clinical) or community (public health) levels may improve self-esteem among this high-risk population, which could potentially influence subsequent suicide risk.


2015 ◽  
Vol 29 (4) ◽  
pp. 135-146 ◽  
Author(s):  
Miroslaw Wyczesany ◽  
Szczepan J. Grzybowski ◽  
Jan Kaiser

Abstract. In the study, the neural basis of emotional reactivity was investigated. Reactivity was operationalized as the impact of emotional pictures on the self-reported ongoing affective state. It was used to divide the subjects into high- and low-responders groups. Independent sources of brain activity were identified, localized with the DIPFIT method, and clustered across subjects to analyse the visual evoked potentials to affective pictures. Four of the identified clusters revealed effects of reactivity. The earliest two started about 120 ms from the stimulus onset and were located in the occipital lobe and the right temporoparietal junction. Another two with a latency of 200 ms were found in the orbitofrontal and the right dorsolateral cortices. Additionally, differences in pre-stimulus alpha level over the visual cortex were observed between the groups. The attentional modulation of perceptual processes is proposed as an early source of emotional reactivity, which forms an automatic mechanism of affective control. The role of top-down processes in affective appraisal and, finally, the experience of ongoing emotional states is also discussed.


2014 ◽  
Vol 23 (1) ◽  
pp. 103-124 ◽  
Author(s):  
Daniel Kopasker

Existing research has consistently shown that perceptions of the potential economic consequences of Scottish independence are vital to levels of support for constitutional change. This paper attempts to investigate the mechanism by which expectations of the economic consequences of independence are formed. A hypothesised causal micro-level mechanism is tested that relates constitutional preferences to the existing skill investments of the individual. Evidence is presented that larger skill investments are associated with a greater likelihood of perceiving economic threats from independence. Additionally, greater perceived threat results in lower support for independence. The impact of uncertainty on both positive and negative economic expectations is also examined. While uncertainty has little effect on negative expectations, it significantly reduces the likelihood of those with positive expectations supporting independence. Overall, it appears that a general economy-wide threat is most significant, and it is conjectured that this stems a lack of information on macroeconomic governance credentials.


Author(s):  
Anna Peterson

This book examines the impact that Athenian Old Comedy had on Greek writers of the Imperial era. It is generally acknowledged that Imperial-era Greeks responded to Athenian Old Comedy in one of two ways: either as a treasure trove of Atticisms, or as a genre defined by and repudiated for its aggressive humor. Worthy of further consideration, however, is how both approaches, and particularly the latter one that relegated Old Comedy to the fringes of the literary canon, led authors to engage with the ironic and self-reflexive humor of Aristophanes, Eupolis, and Cratinus. Authors ranging from serious moralizers (Plutarch and Aelius Aristides) to comic writers in their own right (Lucian, Alciphron), to other figures not often associated with Old Comedy (Libanius) adopted aspects of the genre to negotiate power struggles, facilitate literary and sophistic rivalries, and provide a model for autobiographical writing. To varying degrees, these writers wove recognizable features of the genre (e.g., the parabasis, its agonistic language, the stage biographies of the individual poets) into their writings. The image of Old Comedy that emerges from this time is that of a genre in transition. It was, on the one hand, with the exception of Aristophanes’s extant plays, on the verge of being almost completely lost; on the other hand, its reputation and several of its most characteristic elements were being renegotiated and reinvented.


Author(s):  
Benedetta Zavatta

Based on an analysis of the marginal markings and annotations Nietzsche made to the works of Emerson in his personal library, the book offers a philosophical interpretation of the impact on Nietzsche’s thought of his reading of these works, a reading that began when he was a schoolboy and extended to the final years of his conscious life. The many ideas and sources of inspiration that Nietzsche drew from Emerson can be organized in terms of two main lines of thought. The first line leads in the direction of the development of the individual personality, that is, the achievement of critical thinking, moral autonomy, and original self-expression. The second line of thought is the overcoming of individuality: that is to say, the need to transcend one’s own individual—and thus by definition limited—view of the world by continually confronting and engaging with visions different from one’s own and by putting into question and debating one’s own values and certainties. The image of the strong personality that Nietzsche forms thanks to his reading of Emerson ultimately takes on the appearance of a nomadic subject who is continually passing out of themselves—that is to say, abandoning their own positions and convictions—so as to undergo a constant process of evolution. In other words, the formation of the individual personality takes on the form of a regulative ideal: a goal that can never be said to have been definitively and once and for all attained.


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