Combined treatment with Sigma1R and A2AR agonists fails to inhibit cocaine self-administration despite causing strong antagonistic accumbal A2AR-D2R complex interactions: the potential role of astrocytes

Previous studies have indicated that acute treatment with the monoamine stabilizer OSU-6162 (5 mg/kg), which has a high affinity for Sigma1R, significantly increased the density of accumbal shell D2R-Sigma1R and A2AR-D2R heteroreceptor complexes following cocaine self-administration. Ex vivo studies using the A2AR agonist CGS21680 also suggested the existence of enhanced antagonistic accumbal A2AR-D2R allosteric interactions after treatment with OSU-6162 during cocaine self-administration. However, a 3-day treatment with OSU-6162 (5 mg/kg) failed to alter the behavioral effects of cocaine self-administration. To test these results and the relevance of OSU-6162 (2.5 mg/kg) and/or A2AR (0.05 mg/kg) agonist interactions, we administered low doses of receptor agonists during cocaine self-administration and assessed their neurochemical and behavioral effects. No effects were observed on cocaine self-administration; however, marked and highly significant increases using the proximity ligation assay (PLA) were induced by the co-treatment on the density of the A2AR-D2R heterocomplexes in the nucleus accumbens shell. Significant decreases in the affinity of the D2R high- and low-affinity agonist binding sites were also observed. Thus, in low doses, the highly significant neurochemical effects observed upon cotreatment with an A2AR agonist and a Sigma1R ligand on the A2AR-D2R heterocomplexes and their enhancement of allosteric inhibition of D2R high-affinity binding are not linked to the modulation of cocaine self-administration. The explanation may be related to an increased release of ATP and adenosine from astrocytes in the nucleus accumbens shell in cocaine self-administration. This can lead to increased activation of the A1R protomer in a putative A1R-A2AR-D2R complex that modulates glutamate release in the presynaptic glutamate synapse. We hypothesized that the integration of changes in presynaptic glutamate release and postjunctional heteroreceptor complex signaling, where D2R plays a key role, result in no changes in the firing of the GABA anti-reward neurons, resulting in no reduction in cocaine self-administration in the present experiments.

Sex-specific effects of different types of prenatal stress on foetal testosterone levels and NMDA expression in mice

Prenatal stress is a critical life event often resulting in mental illnesses in the offspring. The critical developmental processes, which might trigger a cascade of molecular events resulting in mental disorders in adulthood, are still to be elucidated. Here we proposed that sex hormones, particularly testosterone, might determine the "developmental programming" of long-term consequences of prenatal stress in foetuses of both sexes. We observed that severe prenatal stress in the model of repeated corticosterone injections enhanced brain levels of corticosterone and testosterone in male foetuses. The expression of GluN1 and GluN2A, but not GluN2B NMDA receptor subunits were significantly reduced in the brain of stressed male foetuses. However, female foetuses were protected against stress effects on the brain corticosterone and testosterone levels. More moderate types of stress, such as repeated restraint stress and chronic unpredictable stress, did not induce an increase in brain corticosterone in dams and testosterone concentrations in foetuses of both sexes. Moreover, chronic unpredictable stress reduced brain testosterone concentration in male foetuses. Altogether, changes in brain testosterone level might be one of the crucial mechanisms determining the development of long-term consequences of severe prenatal stress in male, but not in female foetuses. Targeting this mechanism might allow to develop principally new prediction and therapeutic approaches for prenatal stress-associated psychiatric disorders.

Trait sensitivity to negative feedback in rats is associated with increased expression of serotonin 5-HT2A receptors in the ventral hippocampus

One of the most important yet still underappreciated mechanisms of depression is distorted cognition, with aberrant sensitivity to negative feedback being one of the best-described examples. As serotonin has been identified as an important modulator of sensitivity to feedback and because the hippocampus has been implicated in the mediation of learning from positive and negative outcomes, the present study aimed to identify differences in the expression of various genes encoding 5-HT receptors in this brain region between the rats displaying trait sensitivity and insensitivity to negative feedback. The results demonstrated that trait sensitivity to negative feedback is associated with increased mRNA expression of the 5-HT2A receptors in the rat ventral hippocampus (vHipp). Further analysis revealed that this increased expression might be modulated epigenetically by miRNAs with a high target score for the Htr2a gene (miR-16-5p and miR-15b-5p). Additionally, although not confirmed at the protein level, trait sensitivity to negative feedback was associated with decreased expression of mRNA encoding the 5-HT7 receptor in the dorsal hippocampus (dHipp). We observed no statistically significant intertrait differences in the expression of the Htr1a, Htr2c, and Htr7 genes in the vHipp and no statistically significant intertrait differences in the expression of the Htr1a, Htr2a, and Htr2c genes in the dHipp of the tested animals. These results suggest that resilience to depression manifested by reduced sensitivity to negative feedback may be mediated via these receptors.

Impact of Mephedrone on Fear Memory in Adolescent Rats: Involvement of Matrix Metalloproteinase-9 (MMP-9) and N-Methyl-D-aspartate (NMDA) Receptor

Treatment of Post-Traumatic Stress Disorder (PTSD) is complicated by the presence of drug use disorder comorbidity. Here, we examine whether conditioned fear (PTSD model) modifies the rewarding effect of mephedrone and if repeated mephedrone injections have impact on trauma-related behaviors (fear sensitization, extinction, and recall of the fear reaction). We also analyzed whether these trauma-induced changes were associated with exacerbation in metalloproteinase-9 (MMP-9) and the GluN2A and GluN2B subunits of N-methyl-D-aspartate (NMDA) glutamate receptor expression in such brain structures as the hippocampus and basolateral amygdala. Male adolescent rats underwent trauma exposure (1.5 mA footshock), followed 7 days later by a conditioned place preference training with mephedrone. Next, the post-conditioning test was performed. Fear sensitization, conditioned fear, anxiety-like behavior, extinction acquisition and relapse were then assessed to evaluate behavioral changes. MMP-9, GluN2A and GluN2B were subsequently measured. Trauma-exposed rats subjected to mephedrone treatment acquired a strong place preference and exhibited impairment in fear extinction and reinstatement. Mephedrone had no effect on trauma-induced MMP-9 level in the basolateral amygdala, but decreased it in the hippocampus. GluN2B expression was decreased in the hippocampus, but increased in the basolateral amygdala of mephedrone-treated stressed rats. These data suggest that the modification of the hippocampus and basolateral amygdala due to mephedrone use can induce fear memory impairment and drug seeking behavior in adolescent male rats.

Adult alcohol drinking and emotional tone are mediated by neutral sphingomyelinase during development in males

Alcohol use, abuse, and addiction, and resulting health hazards are highly sex-dependent with unknown mechanisms. Previously, strong links between the SMPD3 gene and its coded protein neutral sphingomyelinase 2 (NSM) and alcohol abuse, emotional behavior, and bone defects were discovered and multiple mechanisms were identified for females. Here we report strong sex-dimorphisms for central, but not for peripheral mechanisms of NSM action in mouse models. Reduced NSM activity resulted in enhanced alcohol consumption in males, but delayed conditioned rewarding effects. It enhanced the acute dopamine response to alcohol, but decreased monoaminergic systems adaptations to chronic alcohol. Reduced NSM activity increased depression- and anxiety-like behavior, but was not involved in alcohol use for the self-management of the emotional state. Constitutively reduced NSM activity impaired structural development in the brain and enhanced lipidomic sensitivity to chronic alcohol. While the central effects were mostly opposite to NSM function in females, similar roles in bone-mediated osteocalcin release and its effects on alcohol drinking and emotional behavior were observed. These findings support the view that the NSM and multiple downstream mechanism may be a source of the sex-differences in alcohol use and emotional behavior.

Novel Dopamine Transporter Inhibitor, CE-123, Ameliorates Spatial Memory Deficits Induced by Maternal Separation in Adolescent Rats: Impact of Sex

Maternal separation (MS) is a key contributor to neurodevelopmental disorders, including learning disabilities. To test the hypothesis that dopamine signaling is a major factor in this, an atypical new dopamine transporter (DAT) inhibitor, CE-123, was assessed for its potential to counteract the MS-induced spatial learning and memory deficit in male and female rats. Hence, neonatal rats (postnatal day (PND)1 to 21) were exposed to MS (180 min/day). Next, the acquisition of spatial learning and memory (Barnes maze task) and the expression of dopamine D1 receptor, dopamine transporter (DAT), and the neuronal GTPase, RIT2, which binds DAT in the vehicle-treated rats were evaluated in the prefrontal cortex and hippocampus in the adolescent animals. The results show that MS impairs the acquisition of spatial learning and memory in rats, with a more severe effect in females. Moreover, the MS induced upregulation of DAT and dopamine D1 receptors expression in the prefrontal cortex and hippocampus in adolescent rats. Regarding RIT2, the expression was decreased in the hippocampus for both the males and females, however, in the prefrontal cortex, reduction was found only in the females, suggesting that there are region-specific differences in DAT endocytic trafficking. CE-123 ameliorated the behavioral deficits associated with MS. Furthermore, it decreased the MS-induced upregulation of D1 receptor expression level in the hippocampus. These effects were more noted in females. Overall, CE-123, an atypical DAT inhibitor, is able to restore cognitive impairment and dopamine signaling in adolescent rats exposed to MS—with more evident effect in females than males.

Psychiatry training goes virtual: the experience of the first online edition of the EPA Research Summer School

Introduction

The European Psychiatric Association (EPA) Summer School allows psychiatric trainees and early career psychiatrists (ECPs) from all over Europe to meet, network, and learn together. After the 2020 edition being cancelled due to COVID-19, the 10th edition in 2021 focused for the first time on research and was conducted remotely.

Objectives

To provide an overview and feedback about the first Virtual EPA Research Summer School as a new way to encourage international networking during COVID-19.

Methods

The School was organized by the EPA Secretary for Education, and 4 Faculty members. It started with a “breaking the ice session” one week before and then a two-days meeting on 23-24 September 2021 using an online video-platform. This was preceded by all the 21 participants (from 18 different countries) recording a short 4-minute video presentation, which was uploaded and shared with other participants and Faculty.

Results

Participants were divided on a voluntary basis into three working groups: 1) “Drug repurposing: overcoming challenges in pharmacoepidemiology” 2) “Psychopathological research in psychiatry”; 3) “How to conduct a cross-sectional survey?”. The Summer School program was composed of plenary sessions with lectures by the Faculty members, discussion sessions, and working groups time. At the end, each group presented a summary of the work done to the rest of the participants.

Conclusions

Although the remote format limits social interactions during the Summer School, overall participants’ high satisfaction and productivity indicate that not only online formats, but also the topic of research might be covered in future editions.

Disclosure

No significant relationships.

Maternal Separation Alters Ethanol Drinking and Reversal Learning Processes in Adolescent Rats: The Impact of Sex and Glycine Transporter Type 1 (GlyT1) Inhibitor

Adverse early life experiences are associated with an enhanced risk for mental and physical health problems, including substance abuse. Despite clinical evidence, the mechanisms underlying these relationships are not fully understood. Maternal separation (MS) is a commonly used animal model of early neglect. The aim of the current study is to determine whether the N-methyl-D-aspartate receptor (NMDAR)/glycine sites are involved in vulnerability to alcohol consumption (two-bottle choice paradigm) and reversal learning deficits (Barnes maze task) in adolescent rats subjected to the MS procedure and whether these effects are sex dependent. By using ELISA, we evaluated MS-induced changes in the NMDAR subunits (GluN1, GluN2A, GluN2B) expression, especially in the glycine-binding subunit, GluN1, in the prefrontal cortex (PFC) and ventral striatum (vSTR) of male/female rats. Next, we investigated whether Org 24598, a glycine transporter 1 (GlyT1) inhibitor, was able to modify ethanol drinking in adolescent and adult male/female rats with prior MS experience and reversal learning in the Barnes maze task. Our findings revealed that adolescent MS female rats consumed more alcohol which may be associated with a substantial increase in GluN1 subunit of NMDAR in the PFC and vSTR. Org 24598 decreased ethanol intake in both sexes with a more pronounced decrease in ethanol consumption in adolescent female rats. Furthermore, MS showed deficits in reversal learning in both sexes. Org 24598 ameliorated reversal learning deficits, and this effect was reversed by the NMDAR/glycine site inhibitor, L-701,324. Collectively, our results suggest that NMDAR/glycine sites might be targeted in the treatment of alcohol abuse in adolescents with early MS, especially females.

Memantine Prevents the WIN 55,212-2 Evoked Cross-Priming of Ethanol-Induced Conditioned Place Preference (CPP)

The activation of the endocannabinoid system controls the release of many neurotransmitters involved in the brain reward pathways, including glutamate. Both endocannabinoid and glutamate systems are crucial for alcohol relapse. In the present study, we hypothesize that N-methyl-D-aspartate (NMDA) glutamate receptors regulate the ability of a priming dose of WIN 55,212-2 to cross-reinstate ethanol-induced conditioned place preference (CPP). To test this hypothesis, ethanol-induced (1.0 g/kg, 10% w/v, i.p.) CPP (unbiased method) was established using male adult Wistar rats. After CPP extinction, one group of animals received WIN 55,212-2 (1.0 and 2.0 mg/kg, i.p.), the cannabinoid receptor 1 (CB1) agonist, or ethanol, and the other group received memantine (3.0 or 10 mg/kg, i.p.), the NMDA antagonist and WIN 55,212-2 on the reinstatement day. Our results showed that a priming injection of WIN 55,212-2 (2.0 mg/kg, i.p.) reinstated (cross-reinstated) ethanol-induced CPP with similar efficacy to ethanol. Memantine (3.0 or 10 mg/kg, i.p.) pretreatment blocked this WIN 55,212-2 effect. Furthermore, our experiments indicated that ethanol withdrawal (7 days withdrawal after 10 days ethanol administration) down-regulated the CNR1 (encoding CB1), GRIN1/2A (encoding GluN1 and GluN2A subunit of the NMDA receptor) genes expression in the prefrontal cortex and dorsal striatum, but up-regulated these in the hippocampus, confirming the involvement of these receptors in ethanol rewarding effects. Thus, our results show that the endocannabinoid system is involved in the motivational properties of ethanol, and glutamate may control cannabinoid induced relapse into ethanol seeking behavior.

The effect of myo-inositol, vitamin D3 and melatonin on the oocyte quality and pregnancy in in vitro fertilization: a randomized prospective controlled trial

OBJECTIVE

To evaluate the efficacy of a treatment with Myo-inositol (MI) plus melatonin and vitamin D3 in women underwent intra cytoplasmatic sperm injection (ICSI).

PATIENTS AND METHODS

100 women undergoing ICSI procedure were enrolled and randomly divided 1:1 in two groups. The study group was treated with 2 g MI, 50 mg Alpha-Lactalbumin (alpha-LA) and 200 µg folic acid in powder every morning for 6 months (3 months before oocyte pick up and 3 months after ICSI); the same patients underwent treatment with 600 mg MI, 1 mg melatonin plus 200 µg folic acid during the evening for 3 months before oocyte pick up; subsequently the pick up these patients were treated with 600 mg MI, 200 µg folic acid, 1 mg melatonin, 50 µg vitamin D3 as cholecalciferol until the 12th week of gestation. The control group was treated with 200 µg folic acid twice a day. Clinical pregnancy rate was evaluated as primary outcome, followed by blastocyst and oocyte quality, as well as gestational period as secondary outcomes.

RESULTS

Treatment significantly improved blastocyst and oocyte quality in the study group, achieving the 42% of clinical pregnancies vs. 24% in the control group, even though the course of pregnancy did not significantly differ between the groups. However, the mean gestational period was shorter in the control group.

CONCLUSIONS

The supplementation of MI in combination with melatonin in the first 3 months before oocyte pick up and with vitamin D3 in the further 3 months could represent an innovative support for all those women undergoing ICSI.

Neutral Sphingomyelinase is an Affective Valence-Dependent Regulator of Learning and Memory

Sphingolipids and enzymes of the sphingolipid rheostat determine synaptic appearance and signaling in the brain, but sphingolipid contribution to normal behavioral plasticity is little understood. Here we asked how the sphingolipid rheostat contributes to learning and memory of various dimensions. We investigated the role of these lipids in the mechanisms of two different types of memory, such as appetitively and aversively motivated memory, which are considered to be mediated by different neural mechanisms. We found an association between superior performance in short- and long-term appetitively motivated learning and regionally enhanced neutral sphingomyelinase (NSM) activity. An opposite interaction was observed in an aversively motivated task. A valence-dissociating role of NSM in learning was confirmed in mice with genetically reduced NSM activity. This role may be mediated by the NSM control of N-methyl-d-aspartate receptor subunit expression. In a translational approach, we confirmed a positive association of serum NSM activity with long-term appetitively motivated memory in nonhuman primates and in healthy humans. Altogether, these data suggest a new sphingolipid mechanism of de-novo learning and memory, which is based on NSM activity.

The Positive and Negative Outcome of Morphine and Disulfiram Subacute Co-Administration in Rats in the Absence of Ethanol Challenge

Recently, a well-known anti-alcohol agent, disulfiram (DSF), has gain much interest, as it was found to be effective in the treatment of cocaine abusers, thus also giving hope for patients addicted to opioids and other illicit drugs. Therefore, this study was aimed to investigate the possible outcome that might occur within the subacute co-administration of both morphine (MRF) and DSF in rats, but in the absence of ethanol challenge. As observed, intraperitoneal DSF dose-dependently enhanced MRF-mediated analgesia with the maximal efficacy at a dose of 100 mg/kg. Furthermore, MRF-induced tolerance and aggressive behavior were significantly reduced by DSF (100 mg/kg, i.p.) in comparison to MRF solely. Nonetheless, significant blood biochemical markers of hepatotoxicity were found (i.e., alteration in the levels of glutathione, blood urea nitrogen, etc.), following a combination of both drugs. Likewise, histological analysis of liver tissue revealed severe changes in the group of DSF + MRF, which includes swelling, cell death, damage to certain vessels, and hemorrhages into the liver parenchyma. Our findings indicate that DSF should be used with extreme caution, especially within the course of subacute concomitant use with MRF, as several possible side effects may take place.

The impact of 3,4-methylendioxymetamphetamine (MDMA) abstinence on seeking behavior and the expression of the D2-like and mGlu5 receptors in the rat brain using saturation binding analyses

The abundance of research indicates that enriched environment acts as a beneficial factor reducing the risks of relapse in substance use disorder. There is also strong evidence showing the engagement of brain dopaminergic and glutamatergic signaling through the dopamine D₂-like and metabotropic glutamate type 5 (mGlu₅) receptors, respectively, that has a direct impact on drug reward and drug abstinence. The present study involved 3,4-methylendioxymethamphetamine (MDMA) self-administration with the yoked-triad procedure in rats kept under different housing conditions during abstinence - enriched environment (EE) or isolation cage (IC) conditions - aimed at evaluating changes in brain receptors affecting drug-seeking behavior as well as density and affinity of the D₂-like and mGlu₅ receptors in several regions of the animal brain. Our results show that exposure to EE conditions strongly reduced active lever presses during cue-induced drug-seeking. At the neurochemical level, we demonstrated marked decreases of D₂-like receptor affinity in the dorsal striatum in rats previously self-administering MDMA under EE and increases in density under IC conditions. Moreover, we found the increases in the density and decreases in the affinity of the D₂-like receptor in the prefrontal cortex and nucleus accumbens provoked by IC conditions. The mGlu₅ receptor density decreased only in the prefrontal cortex after IC and EE abstinence. Moreover, our study has revealed a clear decrease in mGlu₅ receptor density in the nucleus accumbens in the group actively administering MDMA only under EE conditions. This study demonstrates that housing conditions have impact on drug-seeking behavior in rats during abstinence from MDMA self-administration. The observed changes in the dopamine D₂-like and mGlu₅ receptor B_max and/or K_d values were brain-region specific and related to either pharmacological and/or motivational features of MDMA.

Molecular changes evoked by the beta-lactam antibiotic ceftriaxone across rodent models of substance use disorder and neurological disease

Ceftriaxone is a beta-lactam antibiotic that increases the expression of the major glutamate transporter, GLT-1. As such, ceftriaxone ameliorates symptoms across multiple rodent models of neurological diseases and substance use disorders. However, the mechanism behind GLT-1 upregulation is unknown. The present review synthesizes this literature in order to identify commonalities in molecular changes. We find that ceftriaxone (200 mg/kg for at least two days) consistently restores GLT-1 expression in multiple rodent models of neurological disease, especially when GLT-1 is decreased in the disease model. The same dose given to healthy/drug-naive rodents does not reliably upregulate GLT-1 in any brain region except the hippocampus. Increased GLT-1 expression does not consistently arise from transcriptional regulation, and is likely to be due to trafficking changes. In addition to altered transporter expression, ceftriaxone ameliorates neuropathologies (e.g. tau, amyloid beta, cell death) and aberrant protein expression associated with a number of neurological disease models. Taken together, these results indicate that ceftriaxone remains a strong candidate for treatment of multiple disorders in the clinic.

[Minimally Invasive Posterior Lumbar Interbody Fusion and Instrumentation - Outcomes at 24-Month Follow-up]

PURPOSE OF THE STUDY Minimally invasive posterior lumbar interbody fusion and percutaneous instrumentation were introduced in the clinical practice with the aim to reduce the damage to musculoligamentous structures associated with open surgeries. The purpose of the study is to evaluate the clinical outcomes, radiological results and complications of the group of patients operated with the use of the minimally invasive posterior lumbar interbody fusion technique. MATERIAL AND METHODS The group of 31 patients operated for lumbar degenerative disc disease was followed-up prospectively. The surgical technique included a unilateral microsurgical decompression of the spinal canal with the insertion of interbody cages supplemented by percutaneous transpedicular fixation. The clinical outcomes were evaluated by means of the Oswestry Disability Index (ODI), Macnab classification, VAS score for low back pain (VAS LBP) and lower extremity pain (VAS LE) at 2, 6, 12 and 24 months postoperatively. The success rate of interbody fusion and complications was also assessed. RESULTS The inclusion criteria were met by 29 patients. The mean preoperative ODI score of 68.4 decreased to 25.1 at two-year follow-up (p 0.001). Based on the modified Macnab scale excellent and good outcomes were achieved at two-year-followup by 82.4% patients. The mean value of VAS LBP score decreased from 6.2 to 2.1 and in case of VAS LE from 5.38 to 1.34 (p ˂ 0.001). The mean time of operation was 157 minutes. Solid interbody fusion was achieved in 80% of patients. In one case, revision surgery for dislocation of the interbody cage was performed one year after the operation. A total of five misplaced transpedicular screws (5.2%) were recorded. DISCUSSION Dorsal minimally invasive spinal operational techniques, when compared with the open surgery, result in less iatrogenic injury to paravertebral muscles. From a short-term perspective, there is also less blood loss and lower frequency of infectious complications. Together with the reduction of postoperative pain and shorter hospital stay, they enable faster recovery and rehabilitation with comparable clinical effectiveness of the procedure. Apart from the above-mentioned benefits, also some shortcomings are discussed such as higher frequency of complications, longer time of operation, higher occurrence of implant malposition and higher exposure of the patient and the surgeon to radiation. CONCLUSIONS The minimally invasive posterior lumbar interbody fusion technique resulted in a statistically significant clinical improvement in the ODI, Macnab scale, VAS LBP and VAS LE scores. The percutaneous instrumentation technique shows an acceptable rate of incorrectly inserted screws. Key words: degenerative disc disease, minimally invasive spinal surgery, posterior lumbar interbody fusion, spine stabilization, lumbar interbody fusion complications.

Brain region-dependent changes in the expression of endocannabinoid-metabolizing enzymes in rats following antidepressant drugs

The endocannabinoid (eCB) system plays a role in the pathophysiology of depression. The aim of this study was to investigate the expression of the eCB synthesizing enzymes (N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD) and diacylglycerol lipase α (DAGLα)) and eCB degrading enzymes (fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL)) after acute or chronic administration of antidepressant drugs (imipramine (IMI, 15 mg/kg), escitalopram (ESC, 10 mg/kg) and tianeptine (TIA, 10 mg/kg)). eCB metabolizing enzymes were altered in drug-dependent and brain region-specific fashion. After IMI treatment a reduction was noted in the expression of FAAH protein in the dorsal striatum, MAGL in the frontal cortex and DAGLα in the cerebellum. On the other hand, ESC treatment provoked an increase in the MAGL expression in the prefrontal cortex or NAPE-PLD and in DAGLα in the hippocampus and dorsal striatum, while reducing the FAAH expression in the dorsal striatum. TIA administration increased the levels of all enzymes in the prefrontal cortex as well as elevated DAGLα expression in the frontal cortex and dorsal striatum. In conclusion, our results indicate that changes in the eCBs levels after antidepressant drug treatment were related to the expression of their metabolizing enzymes.

Acute Cocaine Enhances Dopamine D2R Recognition and Signaling and Counteracts D2R Internalization in Sigma1R-D2R Heteroreceptor Complexes

The current study was performed to establish the actions of nanomolar concentrations of cocaine, not blocking the dopamine transporter, on dopamine D2 receptor (D2R)-sigma 1 receptor (δ1R) heteroreceptor complexes and the D2R protomer recognition, signaling and internalization in cellular models. We report the existence of D2R-δ1R heteroreceptor complexes in subcortical limbic areas as well as the dorsal striatum, with different distribution patterns using the in situ proximity ligation assay. Also, through BRET, these heteromers were demonstrated in HEK293 cells. Furthermore, saturation binding assay demonstrated that in membrane preparations of HEK293 cells coexpressing D2R and δ1R, cocaine (1 nM) significantly increased the D2R Bmax values over cells singly expressing D2R. CREB reporter luc-gene assay indicated that coexpressed δ1R significantly reduced the potency of the D2R-like agonist quinpirole to inhibit via D2R activation the forskolin induced increase of the CREB signal. In contrast, the addition of 100 nM cocaine was found to markedly increase the quinpirole potency to inhibit the forskolin-induced increase of the CREB signal in the D2R-δ1R cells. These events were associated with a marked reduction of cocaine-induced internalization of D2R protomers in D2R-δ1R heteromer-containing cells vs D2R singly expressing cells as studied by means of confocal analysis of D2R-δ1R trafficking and internalization. Overall, the formation of D2R-δ1R heteromers enhanced the ability of cocaine to increase the D2R protomer function associated with a marked reduction of its internalization. The existence of D2R-δ1R heteromers opens up a new understanding of the acute actions of cocaine.

Maternal high-fat diet during pregnancy and lactation provokes depressive-like behavior and influences the irisin/brain-derived neurotrophic factor axis and inflammatory factors in male and female offspring in rats

A balanced maternal diet is necessary for the proper health and development of offspring. Recent clinical and preclinical studies have strongly indicated that maternal exposure to a high-fat diet (HFD) can have an irreversible impact on the structure and function of the offspring's brain and affect the immune system, which may predispose the offspring to brain disorders, including depression. The irisin/brain-derived neurotrophic factor (BDNF) axis is a pathway that influences several neurobehavioral mechanisms involved in the pathogenesis of mental disorders. The aim of the present study was to evaluate the influence of a maternal HFD during pregnancy and lactation on depressive-like behavior, serum irisin concentration and hippocampal levels of irisin, BDNF and inflammatory factors (interleukin-1α, interleukin-6 and tumor necrosis factor-α) in adolescent and adult male and female offspring. The main findings indicate that offspring exposed to a maternal HFD are characterized by an increased immobility time in the forced swimming test at both stages of life. Our results showed that a maternal HFD decreased serum and hippocampal irisin levels in females on postnatal day (PND) 28 and decreased the level of interleukin-1α at postnatal days 28 and 63 in the hippocampus. Interestingly, significant age-dependent changes were observed in irisin, BDNF and interleukin levels. To summarize, our study indicates that a maternal HFD during pregnancy and lactation provokes depressive-like behaviour in the offspring. However, despite the observed changes in the levels of irisin and IL-1α in females, further investigations are required to identify the underlying molecular mechanism associated with depressive-like behavior in the offspring of HFD-fed dams.

Regorafenib therapy in metastatic colorectal cancer patients: markers and outcome in an actual clinical setting

The oral multikinase inhibitor regorafenib had beneficial effects in randomized clinical phase III trials compared to the placebo in patients with metastatic colorectal cancer (mCRC) who progressed on standard therapies. The factors which influence regorafenib response and therapy sequence during treatment history are still highly discussed, and herein we analyzed the therapy algorithm, outcome and clinical markers following regorafenib application in a single center register study. Clinical data for 48 metastatic colorectal cancer patients were collected from 01.01.2013 to 31.12.2016. Treatment effects according to various patient and tumor characteristics were evaluated using univariate and multivariate Cox proportional hazard regression models. The 48 patients comprised 14 (29%) females and 34 (71%) males, with mean age 64.2±9 and ECOG 0-1. Progression free survival under regorafenib therapy was 2.9 months (quartiles 2.2; 4.4) and the overall response rate was 2 (4%) and disease control rate was 19 (40%). Overall survival (OS) and progression free survival (PFS) were investigated under regorafenib in the chemotherapy regimen given immediately before and afterthis treatment. Variables including tumor localization, Ras status, CEA and CA 19-9 plasma levels were analyzed for their impact on PFS, and the regorafenib-related adverse events were also observed. Our study confirms the efficacy of regorafenib in a real-life setting. We established that response rate and PFS in regorafenib treatment are independent of tumor localization, Ras status or biomarkers such as CEA and CA 19-9. Trifluridin/tripacil application or re-induction of chemotherapy +/- target therapy was effective following regorafenib therapy.

[First Experience with Cranioplasty Using the Polyetheretherketone (PEEK) Implant - Retrospective Five-Year Follow-up Study]

PURPOSE OF THE STUDY Cranioplasty is currently the most common neurosurgical procedure. The purpose of this study is to describe the first experience with successful use of the Cranio-Oss (PEEK) custom implant for cranioplasty. MATERIAL AND METHODS In the period 2012 to 2013, a total of 26 cranioplasties were performed. In fourteen patients, their own bone flap was used for reconstruction. In four cases, a synthetic Cranio-Oss bone implant made of PEEK was used. In six patients, the defect was covered by an intraoperatively-made Palacos implant and in two cases, minor defects were covered with a titanium mesh. The patients were followed up for at least five years. Cranio-Oss is a cranial implant made from polyetheretherketone (PEEK), a synthetic biocompatible material. The implant is created using the CAD/CAM method in the shape of the bone defect based on the CT scan. Creating optimal roughness of the implant surface and of the surface of the contact area attached to the bone bed is controlled and included already in the strategy for machining individual areas of the implant during its manufacturing at a 5-axis machining centre. RESULTS The Cranio-Oss implant was used in four younger patients to cover larger and complex-shaped defects. The mean age of patients in this group was 47 years. The implant was fixed to the skull by micro-plates. In all the cases the wound healed well with good cosmetic results without the necessity of revision with respect to the used implant. The follow-up CT scans always showed the implant in situ with no signs of malposition. DISCUSSION Autologous bone flap is the most suitable material for defect reconstruction after craniectomy. This option is affordable and represents one of the best methods of reconstruction of defects after craniectomy in terms of cosmetic results. In some cases, the original skull cannot be used for cranioplasty (e.g. if destructed by tumourous process, infected or in comminuted fractures). In such cases, the defect needs to be managed using a synthetic implant. In case of extensive defects, the most suitable option is a custom made implant from advanced biomaterials. CONCLUSIONS Authors prefer using autologous bone flaps during cranioplasty. In cases where this method is unavailable, a synthetic bone substitute has to be used. The first medium-term experience with the use of a Cranio-Oss implant made of PEEK showed that it is a suitable alternative to the patient's own bone. No complications associated with this synthetic implant were reported and its use to manage skull defects can be strongly recommended. With respect to legal and accreditationrelated difficulties connected with bone fragments storage and thanks to the continuous cost reduction of synthetic implants will their importance grow in the future. Key words: decompressive craniectomy, bone substitute, craniotrauma.

A2AR-D2R Heteroreceptor Complexes in Cocaine Reward and Addiction

The concept of allosteric receptor-receptor interactions in G protein-coupled receptor homo- and heteroreceptor complexes in which they physically interact provides a new dimension to molecular integration in the brain. The receptor-receptor interactions dynamically change recognition, pharmacology, signaling, and trafficking of the participating receptors. Among the receptor complexes, disruption of the A2A receptor-dopamine D2 receptor (A2AR-D2R) complex by an A2AR agonist has been shown to fully block the inhibition of cocaine self-administration. Cocaine induced pathological A2AR-D2R-Sigma1R complexes may form a long-term memory with a strong and permanent D2R brake, leading to cocaine addiction. These heteroreceptor complexes can potentially be targeted for future pharmacotherapy of cocaine addiction by using heterobivalent compounds or A2AR-D2R receptor interface-interfering peptides that disrupt the A2AR-D2R-Sigma1R complexes.

Disruption of A2AR-D2R Heteroreceptor Complexes After A2AR Transmembrane 5 Peptide Administration Enhances Cocaine Self-Administration in Rats

Antagonistic allosteric A2AR-D2R receptor-receptor interactions in heteroreceptor complexes counteract cocaine self-administration and cocaine seeking in rats as seen in biochemical and behavioral experiments. It was shown that the human A2AR transmembrane five (TM5) was part of the interface of the human A2AR-D2R receptor heteromer. In the current paper, the rat A2AR synthetic TM5 (synthTM5) peptide disrupts the A2AR-D2R heteroreceptor complex in HEK293 cells as shown by the bioluminescence resonance energy transfer method. Rat A2AR synthTM5 peptide, microinjected into the nucleus accumbens, produced a complete counteraction of the inhibitory effects of the A2AR agonist CGS21680 on cocaine self-administration. It was linked to a disappearance of the accumbal A2AR-D2R heteroreceptor complexes and the A2AR agonist induced inhibition of D2R recognition using proximity ligation assay and biochemical binding techniques. However, possible effects of the A2AR synthTM5 peptide on accumbal A2AR-D3R and A2AR-D4R heteroreceptor complexes remain to be excluded. Evidence is provided that accumbal A2AR-D2R-like heteroreceptor complexes with their antagonistic receptor-receptor interactions can be major targets for treatment of cocaine use disorder.

Dopamine D2 Receptor Supersensitivity as a Spectrum of Neurotoxicity and Status in Psychiatric Disorders

Abnormality of dopamine D₂ receptor (D₂R) function, often observed as D₂R supersensitivity (D₂RSS), is a commonality of schizophrenia and related psychiatric disorders in humans. Moreover, virtually all psychotherapeutic agents for schizophrenia target D₂R in brain. Permanent D₂RSS as a feature of a new animal model of schizophrenia was first reported in 1991, and then behaviorally and biochemically characterized over the next 15-20 years. In this model of schizophrenia characterized by production of D₂RSS in ontogeny, there are demonstrated alterations of signaling processes, as well as functional links between the biologic template of the animal model and ability of pharmacotherapeutics to modulate or reverse biologic and behavioral modalities toward normality. Another such animal model, featuring knockout of trace amine-associated receptor 1 (TAAR1), demonstrates D₂RSS with an increase in the proportion of D₂R in the high-affinity state. Currently, TAAR1 agonists are being explored as a therapeutic option for schizophrenia. There is likewise an overlay of D₂RSS with substance use disorder. The aspect of adenosine A_2A-D₂ heteroreceptor complexes in substance use disorder is highlighted, and the association of adenosine A_2A receptor antagonists in discriminative and rewarding effects of psychostimulants is outlined. In summary, these new animal models of schizophrenia have face, construct, and predictive validity, and distinct advantages over earlier models. While the review summarizes elements of D₂RSS in schizophrenia per se, and its interplay with substance use disorder, a major focus is on presumed new molecular targets attending D₂RSS in schizophrenia and related clinical entities.

Ceramide and Its Related Neurochemical Networks as Targets for Some Brain Disorder Therapies

Correlational and causal comparative research link ceramide (Cer), the precursor of complex sphingolipids, to some psychiatric (e.g., depression, schizophrenia (SZ), alcohol use disorder, and morphine antinociceptive tolerance) and neurological (e.g., Alzheimer's disease (AD), Parkinson disease (PD)) disorders. Cer generation can occur through the de novo synthesis pathway, the sphingomyelinase pathways, and the salvage pathway. The discoveries that plasma Cer concentration increase during depressive episodes in patients and that tricyclic and tetracyclic antidepressants functionally inhibit acid sphingomyelinase (ASM), the enzyme that catalyzes the degradation of sphingomyelin to Cer, have initiated a series of studies on the role of the ASM-Cer system in depressive disorder. Disturbances in the metabolism of Cer or SM are associated with the occurrence of SZ and PD. In both PD and SZ patients, the elevated levels of Cer or SM in the brain regions were associated with the disease. AD patients showed also an abnormal metabolism of brain Cer at early stages of the disease which may suggest Cer as an AD biomarker. In plasma of AD patients and in AD transgenic mice, ASM activity was increased. In contrast, partial ASM inhibition of Aβ deposition improved memory deficits. Furthermore, in clinical and preclinical research, ethanol enhanced activation of ASM followed by Cer production. Limited data have shown that Cer plays an important role in the development of morphine antinociceptive tolerance. In summary, clinical and preclinical findings provide evidence that targeting the Cer system should be considered as an innovative translational strategy for some brain disorders.

Antimicrobial activity and thiosulfinates profile of a formulation based on Allium cepa L. extract

Background

Allium species extracts including Allium cepa L. contain sulfur compounds, known for their antiplatelet, antimicrobial, antineoplasic activities.

Methodology

Antibacterial activity of a formulation based on A. cepa extracts-liquid and lyophilized samples, has been demonstrated using two classes of bacteria: Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) and three methods: discs soaked with liquid extract, the wells method in the culture medium, filled with the liquid extract and lyophilized formulation extracts transformed by the incorporation of ultrapure water. The second part of this study includes identification of thiosulfinates compounds from the studied samples by high performance liquid chromatography - mass spectrometry (HPLC-MS).

Results

The most important inhibition and the highest antibacterial effficiency were observed against Gram-positive bacteria, such as Staphylococcus aureus. The HPLC-MS thiosulfinates profile of the tested formulation extracts shows the presence of seven thiosulfinate compounds, MeS(O)S 1-propenyl (E,Z); n-PrS(O)S 1-propenyl-(E); n-PrS(O)S 1-propenyl-(Z); trans-zwiebelane; n-PrS(O)CHEtSS-1propenyl; 1-propenylS(O)CHEtSS1-propenyl, which may be responsible for antibacterial activity.

Conclusion

Testing antimicrobial effects using the three mentioned methods confirmed the antimicrobial activity of the tested samples based on A. cepa extracts, with a demonstrated content of seven thiosulfinate compounds.

Cocaine self-administration specifically increases A2AR-D2R and D2R-sigma1R heteroreceptor complexes in the rat nucleus accumbens shell. Relevance for cocaine use disorder

Adenosine 2A receptor (A2AR) agonists were indicated to reduce cocaine reward and cocaine seeking mainly through activation of antagonistic allosteric A2AR-dopamine D2R (D2R) interactions in A2AR-D2R heteroreceptor complexes. Furthermore, it was shown that modulation of cocaine reward involves antagonistic A2AR-D2R interactions in the ventral but not the dorsal striatum in rats. In the current work the proximity ligation assay (PLA) was used to further study the A2AR-D2R heteroreceptor complexes in the nucleus accumbens shell and core as well as the dorsal striatum under the influence of cocaine self-administration in rats. A significant increase in the A2AR-D2R PLA positive clusters was observed in the nucleus accumbens shell but not in the other regions vs yoked saline controls using the duolink software. Additionally, cocaine self-administration evoked a selective and significant increase in the density of D2R-sigma1R positive clusters in the nucleus accumbens shell vs yoked saline controls, while a significant reduction of the density of the D2R-sigma1R positive clusters was found in the dorsal part of the dorsal striatum. The results suggest that cocaine self-administration can reorganize A2AR and D2R into increased A2AR-D2R heteroreceptor complexes in the nucleus accumbens shell associated with increases in the D2R-sigma1R heteroreceptor complexes in this region. This reorganization can contribute to the demonstrated anti-cocaine actions of A2A receptor agonists and the putative formation of A2AR-D2R-sigma1R heterocomplexes.

Understanding the Role of GPCR Heteroreceptor Complexes in Modulating the Brain Networks in Health and Disease

The introduction of allosteric receptor-receptor interactions in G protein-coupled receptor (GPCR) heteroreceptor complexes of the central nervous system (CNS) gave a new dimension to brain integration and neuropsychopharmacology. The molecular basis of learning and memory was proposed to be based on the reorganization of the homo- and heteroreceptor complexes in the postjunctional membrane of synapses. Long-term memory may be created by the transformation of parts of the heteroreceptor complexes into unique transcription factors which can lead to the formation of specific adapter proteins. The observation of the GPCR heterodimer network (GPCR-HetNet) indicated that the allosteric receptor-receptor interactions dramatically increase GPCR diversity and biased recognition and signaling leading to enhanced specificity in signaling. Dysfunction of the GPCR heteroreceptor complexes can lead to brain disease. The findings of serotonin (5-HT) hetero and isoreceptor complexes in the brain over the last decade give new targets for drug development in major depression. Neuromodulation of neuronal networks in depression via 5-HT, galanin peptides and zinc involve a number of GPCR heteroreceptor complexes in the raphe-hippocampal system: GalR1-5-HT1A, GalR1-5-HT1A-GPR39, GalR1-GalR2, and putative GalR1-GalR2-5-HT1A heteroreceptor complexes. The 5-HT1A receptor protomer remains a receptor enhancing antidepressant actions through its participation in hetero- and homoreceptor complexes listed above in balance with each other. In depression, neuromodulation of neuronal networks in the raphe-hippocampal system and the cortical regions via 5-HT and fibroblast growth factor 2 involves either FGFR1-5-HT1A heteroreceptor complexes or the 5-HT isoreceptor complexes such as 5-HT1A-5-HT7 and 5-HT1A-5-HT2A. Neuromodulation of neuronal networks in cocaine use disorder via dopamine (DA) and adenosine signals involve A2AR-D2R and A2AR-D2R-Sigma1R heteroreceptor complexes in the dorsal and ventral striatum. The excitatory modulation by A2AR agonists of the ventral striato-pallidal GABA anti-reward system via targeting the A2AR-D2R and A2AR-D2R-Sigma1R heteroreceptor complex holds high promise as a new way to treat cocaine use disorders. Neuromodulation of neuronal networks in schizophrenia via DA, adenosine, glutamate, 5-HT and neurotensin peptides and oxytocin, involving A2AR-D2R, D2R-NMDAR, A2AR-D2R-mGluR5, D2R-5-HT2A and D2R-oxytocinR heteroreceptor complexes opens up a new world of D2R protomer targets in the listed heterocomplexes for treatment of positive, negative and cognitive symptoms of schizophrenia.

Cocaine self-administration, extinction training and drug-induced relapse change metabotropic glutamate mGlu5 receptors expression: Evidence from radioligand binding and immunohistochemistry assays

Several behavioral findings highlight the importance of glutamatergic transmission and its metabotropic receptor type 5 (mGlu₅) in the controlling of cocaine reward and seeking behaviors. The molecular or neurochemical nature of such interactions is not well recognized, so in the present paper we determine if cocaine self-administration and extinction/reinstatement models with the yoked triad control procedure alter mGlu₅ receptor density in rats. [³H]MPEP was used to evaluate mGlu₅ receptors density and affinity in selected brain structures, while immunofluorescence analysis was used to detect changes in mGlu₅ receptors' brain location. Cocaine self-administration and yoked cocaine delivery evoked a significant elevation in mGlu₅ receptors' density in the dorsal striatum, while receptor protein expression was importantly elevated in the substantia nigra and reduced in the nucleus accumbens shell. Cocaine administration followed by 10 extinction training sessions resulted in biphasic mGlu₅ receptor density changes in the prefrontal cortex-nucleus accumbens pathway. mGlu₅ receptors' up-regulation was noted for cocaine self-administration and extinction training in the hippocampus and in yoked cocaine controls following drug abstinence in the dorsal striatum. A cocaine priming dose (but not a saline priming) resulted in a significant decrease of mGlu₅ receptors' density in the nucleus accumbens of rats previously treated with the drug and in the hippocampus of rats previously self-administered cocaine. The latter decrease in mGlu₅ receptors' density and protein expression in the hippocampus was parallel to an increase in [³H]MPEP affinity and opposite to a rise observed after single cocaine administration (ip) to drug-naïve yoked saline controls. Additionally, we also observed a significant elevation in the protein expression of the tested receptors in the limbic cortex in both cocaine groups. The present results shown modality dependent and brain-region specific changes in mGlu₅ receptors' localization and membrane specific binding.

Cocaine self-administration differentially affects allosteric A2A-D2 receptor-receptor interactions in the striatum. Relevance for cocaine use disorder

In the current study behavioral and biochemical experiments were performed to study changes in the allosteric A2AR-D2R interactions in the ventral and dorsal striatum after cocaine self-administration versus corresponding yoked saline control. By using ex vivo [(3)H]-raclopride/quinpirole competition experiments, the effects of the A2AR agonist CGS 21680 (100 nM) on the KiH and KiL values of the D2-like receptor (D2-likeR) were determined. One major result was a significant reduction in the D2-likeR agonist high affinity state observed with CGS 21680 after cocaine self-administration in the ventral striatum compared with the yoked saline group. The results therefore support the hypothesis that A2AR agonists can at least in part counteract the motivational actions of cocaine. This action is mediated via the D2-likeR by targeting the A2AR protomer of A2AR-D2-like R heteroreceptor complexes in the ventral striatum, which leads to the reduction of D2-likeR protomer recognition through the allosteric receptor-receptor interaction. In contrast, in the dorsal striatum the CGS 21680-induced antagonistic modulation in the D2-likeR agonist high affinity state was abolished after cocaine self-administration versus the yoked saline group probably due to a local dysfunction/disruption of the A2AR-D2-like R heteroreceptor complexes. Such a change in the dorsal striatum in cocaine self-administration can contribute to the development of either locomotor sensitization, habit-forming learning and/or the compulsive drug seeking by enhanced D2-likeR protomer signaling. Potential differences in the composition and stoichiometry of the A2AR-D2R heteroreceptor complexes, including differential recruitment of sigma 1 receptor, in the ventral and dorsal striatum may explain the differential regional changes observed in the A2A-D2-likeR interactions after cocaine self-administration.

Neurotensin: A role in substance use disorder?

Neurotensin is a tridecapeptide originally identified in extracts of bovine hypothalamus. This peptide has a close anatomical and functional relationship with the mesocorticolimbic and nigrostriatal dopamine system. Neural circuits containing neurotensin were originally proposed to play a role in the mechanism of action of antipsychotic agents. Additionally, neurotensin-containing pathways were demonstrated to mediate some of the rewarding and/or sensitizing properties of drugs of abuse.This review attempts to contribute to the understanding of the role of neurotensin and its receptors in drug abuse. In particular, we will summarize the potential relevance of neurotensin, its related compounds and neurotensin receptors in substance use disorders, with a focus on the preclinical research.

On the role of A₂A and D₂ receptors in control of cocaine and food-seeking behaviors in rats

Recent studies indicate that adenosine may influence dopamine neurotransmission via A2A receptors which antagonistically interact with D2 receptor-mediated signaling in the brain. We examined the effects of selective A2A receptor ligands such as the agonist CGS 21680 and the antagonists KW 6002 or SCH 58261 as well as of the D2-like receptor antagonist raclopride on reinstatement of cocaine seeking induced by cocaine, the cocaine-conditioned cue, or the D2-like receptor agonist quinpirole in rats. For comparison, effects of the A2A receptor ligands on reinstatement of food seeking were also studied. CGS 21680 significantly attenuated the reinstatement of cocaine (ip) seeking, and even more potently it reduced quinpirole (ip) or the cue-induced relapse of cocaine seeking as well as cue-induced food seeking. A potent reduction toward the cocaine-, quinpirole-, or cue-induced reinstatement of cocaine seeking was seen with raclopride. Pretreatment with KW 6002 or SCH 58261 reinstated cocaine seeking, and such increases were blocked by raclopride. In the higher doses, KW 6002 or SCH 58261 evoked food-seeking. In combination with the subthreshold dose of cocaine (2.5 mg/kg) or with the cue, low doses of KW 6002 but not SCH 58261 reinstated cocaine-seeking behavior, while none of the A2A receptor antagonists affected the cue-induced food-seeking behavior. The results indicate that A2A activation and D2-like receptor blockade counteract cocaine and food relapse. It is proposed that A2A receptor- and D2 receptor-mediated adenosine and dopamine signaling antagonistically interact in the striato-pallidal GABA neurons to regulate cocaine and food-seeking behavior.

Diversity and Bias through Receptor-Receptor Interactions in GPCR Heteroreceptor Complexes. Focus on Examples from Dopamine D2 Receptor Heteromerization

Allosteric receptor-receptor interactions in GPCR heteromers appeared to introduce an intermolecular allosteric mechanism contributing to the diversity and bias in the protomers. Examples of dopamine D2R heteromerization are given to show how such allosteric mechanisms significantly change the receptor protomer repertoire leading to diversity and biased recognition and signaling. In 1980s and 1990s, it was shown that neurotensin (NT) through selective antagonistic NTR-D2 like receptor interactions increased the diversity of DA signaling by reducing D2R-mediated dopamine signaling over D1R-mediated dopamine signaling. Furthermore, D2R protomer appeared to bias the specificity of the NTR orthosteric binding site toward neuromedin N vs. NT in the heteroreceptor complex. Complex CCK2R-D1R-D2R interactions in possible heteroreceptor complexes were also demonstrated further increasing receptor diversity. In D2R-5-HT2AR heteroreceptor complexes, the hallucinogenic 5-HT2AR agonists LSD and DOI were recently found to exert a biased agonist action on the orthosteric site of the 5-HT2AR protomer leading to the development of an active conformational state different from the one produced by 5-HT. Furthermore, as recently demonstrated allosteric A2A-D2R receptor-receptor interaction brought about not only a reduced affinity of the D2R agonist binding site but also a biased modulation of the D2R protomer signaling in A2A-D2R heteroreceptor complexes. A conformational state of the D2R was induced, which moved away from Gi/o signaling and instead favored β-arrestin2-mediated signaling. These examples on allosteric receptor-receptor interactions obtained over several decades serve to illustrate the significant increase in diversity and biased recognition and signaling that develop through such mechanisms.

Why we use AT.Lisa multifocals?

In this paper, the authors try to motivate their preference for implanting AT.Lisa Multifocals from all other premium IOL's from the market. It is emphasized, through clinical examples, that their choice comes after a long experience with this type of mul- tifocals IOL's. We make a short presentation of this particular type of MIOL's with their good but also weak points and try to motivate our decision to change from other types. We present the steps that each patient has to follow in our clinic prior to surgery itself, stressing out the idea that the discussion with the patient is very important in taking a decision regarding the implantation of a Premium IOL.

Effects of cocaine self-administration and extinction on D2 -like and A2A receptor recognition and D2 -like/Gi protein coupling in rat striatum

Striatal adenosine (A)2 -dopamine (D)2 receptor (R) heteromers exist with antagonistic interactions. We have studied these Rs and their interactions during cocaine self-administration and extinction using a 'yoked' protocol to understand the role of motivational mechanisms behind the adaptive observed. In the ventral striatum, a significant increase in the A2A R density was observed in rats that received 'yoked' cocaine during maintenance phase and following its extinction while this significant increase was only observed after extinction from cocaine self-administration. In the dorsal striatum, a significant increase in the affinity of A2A Rs was determined in the two groups of rats that received cocaine during maintenance. D2 -like Rs were significantly increased in the dorsal striatum of animals that received 'yoked' cocaine during maintenance. In the rat dorsal, but not the ventral, striatum significant reductions in the EC50 values for dopamine and increases in the guanosine5'-([γ]-thio)triphosphate (GTPγS) accumulation were observed following active and passive cocaine injections during maintenance. After 10-day extinction, a significant reduction of the Bmax value of GTPγS accumulation was demonstrated in the dorsal striatum of rats previously self-administered cocaine, while a significant reduction of the EC50 value for dopamine in the ventral striatum was found in the 'yoked' cocaine group. By comparing the cocaine self-administration group with the 'yoked' cocaine group, evidence for the existence of motivational mechanisms that guide adaptive changes in the A2A R and D2 R and in the D2 -Gi coupling differentially developed in the ventral and dorsal striatum during cocaine maintenance and its extinction has been demonstrated.

[Pseudoexfoliative glaucoma]

Secondary open-angle glaucoma, characterized by the deposition of whitish, fibrillar material within the structures of the anterior segment of the eye.

[Protein S100b in differential diagnosis of brain concussion and superficial scalp injury in inebriated patients]

INTRODUCTION

Concussion cannot be differentiated from superficial scalp injury, especially in inebriated or uncooperative patients. This can have serious medical or forensic consequences. The aim of the study was to determine whether serum concentrations of S-100b in mild traumatic brain injury (MTBI) patients are significantly higher than those in patients with superficial scalp injury with scalp wound and alcohol intoxication.

MATERIAL AND METHODS

A total of 50 patients with head injury, 25 with mild concussion without scalp wound and alcohol intoxication, 25 superficial scalp injury patients with scalp wound and clinical signs of inebriety. Neurological status and cranial CT scan were evaluated 60-120 minutes after injury in all the 50 patients to exclude focal cerebral injury or skull fracture.

RESULTS

The serum levels of S-100b were significantly increased in patients with concussion (median 0.36 ± 0.15 μg/l ) in comparison with the group of patients with scalp injury and alcohol intoxication (median 0.09 ± 0.002 μg/l). All 50 patients had a normal cranial CT finding and neurological status. In all superficial scalp injury patients alcohol intoxication was confirmed (0.96 - 3.11š).

CONCLUSION

We proved significantly higher values of S-100b in patients with brain concussion. Diagnostically decisive value of S-100b concentration in the serum was set at 146 μg/l and higher (94% sensitivity and 100% specificity). Alcohol intoxication (up to 3.11 š) and scalp wound seem to have had no crucial impact on serum S-100b level.