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Objective: The objective of the study was to propose a candidate animal model of absence status epilepticus induced by specific alpha‐2a adrenergic receptor (α2AR) activation. We also aim to investigate the responsiveness of this model to classical anti‐status or anti‐absence medications. Methods: An α2AR agonist, dexmedetomidine (DEX), was injected intracerebroventricularly into adult rats with genetic absence epilepsy, and their electroencephalography (EEG) was recorded. The total duration, number, and mean duration of each spike‐and‐wave discharges (SWDs) were evaluated. The blocks of absence status events were classified as the initial and second sets of absence statuses. Ethosuximide (ETX) was administered as a pretreatment to another group of rats and later injected with 2.5 μg DEX. In addition, ETX, valproic acid (VPA), diazepam (DIAZ), and atipamezole (ATI) were administered after induced status‐like events following DEX administration. Power spectral characteristics and coherence analysis were performed on the EEG to assess the absence status events and sleep. Results: The 2.5 μg dose of DEX increased the total SWD duration and induced continuous SWDs up to 26 min. Following the initial absence status event, sleep was induced; then, the second period of absence status‐like activities were initiated. ETX pretreatment blocked the occurrence of absence status‐like activities. Power spectral density analyses revealed that DEX‐induced post‐sleep activities had higher power in delta frequency band (1–4 Hz) and attenuated power of 7 Hz harmonics (14 and 21 Hz) than the pre‐injection seizure. The mean duration of SWDs were decreased in all the groups, but occasional prolonged activities were seen in ETX or VPA‐injected rats but not with DIAZ or ATI. Significance: This study presents an absence status epilepticus animal model that is activated by α2AR activation to investigate the pathophysiological role of absence status. Unlike other agents ATI switched off the second set of absence statuses to normal SWDs, without sedation or lethargy, can show it may preferentially block absence status‐like activity. The Plain Language Summary: This study proposes a rat model for prolonged seizures, resembling absence status epilepticus. Activating the brain's alpha‐2a adrenergic receptor with dexmedetomidine induced seizures lasting up to 26 minutes. Ethosuximide pretreatment and post‐treatment with valproic acid, diazepam, and atipamezole decreased induced seizures. The findings suggest this model is valuable for studying absence status epilepticus. In addition, atipamezole normalized abnormal seizures without sedation, hinting at its potential for targeted treatment and further research. [ABSTRACT FROM AUTHOR]

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In this article, we test the hypothesis that beliefs about the ideal mother are convergent across cultures and that these beliefs overlap considerably with attachment theory's notion of the sensitive mother. In a sample including 26 cultural groups from 15 countries around the globe, 751 mothers sorted the Maternal Behavior Q-Set to reflect their ideas about the ideal mother. The results show strong convergence between maternal beliefs about the ideal mother and attachment theory's description of the sensitive mother across groups. Cultural group membership significantly predicted variations in maternal sensitivity belief scores, but this effect was substantially accounted for by group variations in socio-demographic factors. Mothers living in rural versus urban areas, with a low family income, and with more children, were less likely to describe the ideal mother as highly sensitive. Cultural group membership did remain a significant predictor of variations in maternal sensitivity belief scores above and beyond socio-demographic predictors. The findings are discussed in terms of the universal and culture-specific aspects of the sensitivity construct.

Objective: Valproate (VPA) and levetiracetam (LEV) are frequently prescribed for the management of idiopathic generalized seizures; however, their welldocumented teratogenic effects raise concerns when administered to pregnant epileptic patients. This study aimed to assess the impact of VPA and LEV exposure during pregnancy on Genetic Absence Epilepsy Rats from Strasbourg (GAERS). Methods: Female GAERS rats were categorized into three groups: saline-treated (n=6), VPA-treated (200 mg/kg, n=4), and LEV-treated (50 mg/kg, n=6). Intraperitoneal injections were initiated from mating start and continued until partition. Locomotor activity and anxiety-like behavior were evaluated using openfield and hole-board tests for the VPA-treated and VPA- and LEV-treated groups; respectively. These tests were conducted both before and during pregnancy. Results: Across all groups, open-field testing demonstrated a tendency toward reduced locomotor activity parameters compared with pre-pregnancy, with VPA treatment showing significance (p<0.05). The hole-board test indicated a trend toward decreased rearing and hole exploration, coupled with increased freezing behavior in the saline- and VPA-treated groups. The LEV-treated group showed an elevation in freezing behavior and a decline in hole exploration. Conclusion: Although minimal effects on anxiety-like behaviors were noted in anti-seizure drug-treated rats, subtle tendencies were evident in the holeboard test. VPA and LEV administration resulted in depressive parameters in the locomotor activity test. These findings emphasize the need for caution when prescribing and using VPA and the LEV during pregnancy in terms of maternal behavior and mood. [ABSTRACT FROM AUTHOR]

Objective: The role of α2A adrenergic receptors (α2AARs) in absence epilepsy is not well characterized. Therefore, we investigated the outcomes of the specific antagonism of α2AARs on the spike‐and‐wave discharges (SWDs) in genetic absence epilepsy rats from Strasbourg (GAERSs), together with its influence on the behavior and second messenger systems, which may point to the mechanisms to which a possible SWD modulation can be related. Methods: Atipamezole, an α2AAR antagonist, was administered intracerebroventricularly to the adult GAERSs, and electroencephalography (EEG) was conducted. The cumulative duration and number of SWDs, and the mean duration of each SWD complex were counted. The relative power of the EEG frequency bands and behavioral activity after the acute application of two doses (12 and 31 μg/5 μL) of atipamezole were evaluated. The levels of cyclic adenosine monophosphate and calcium/calmodulin‐dependent kinase II (CaMKII) were measured in the cortex, thalamus, and hippocampus of naive Wistar rats and GAERSs, administered with artificial cerebrospinal fluid (aCSF) as a vehicle, or either acute or chronic atipamezole (12 μg), the latter being administered for 5 consecutive days. Results: Atipamezole significantly suppressed SWDs dose‐dependently, without affecting the relative power values of EEG frequency spectrum. The stereotypic activity was significantly lower in both naive Wistar rats and GAERSs receiving the highest dose (31 μg) of atipamezole compared to GAERSs receiving aCSF. In GAERSs, CaMKII levels were found to be higher in the thalamus after the acute and chronic application of SWD‐suppressing doses of atipamezole (12 and 31 μg) compared to aCSF. Significance: This study emphasizes the α2AR‐related modulation of absence epilepsy and particularly the significance of α2AR antagonism in suppressing SWDs. Atipamezole's SWD‐suppressive actions may be through CaMKII‐mediated second messenger systems in the thalamus. [ABSTRACT FROM AUTHOR]

Objective: Dexmedetomidine induces a two-phase of events: an initial period of absence status-like activity followed by sleep, then an immediate switch from sleep to the second period of absence status-like events (Yavuz et al, 2022). We aim to explore the effects of the de-activation of 2AR by atipamezole on these state transitions induced by dexmedetomidine in Genetic Absence Epilepsy Rats from Strasbourg (GAERS). Methods: Specific a2AR agonist, dexmedetomidine (2.5 µg), was administered via intracerebroventricular injection to adult GAERS (n=8) to induce absence status-like events. When the initial absence status-like events were triggered, atipamezole (1 mg/kg) was injected intraperitoneally. Electroencephalography (EEG) recordings were obtained 30 min before the initial administration of dexmedetomidine and 2 hours after atipamezole. The duration of SWDs and prolonged SWDs; we defined as absence status-like activities and the anesthesia sleep between were analyzed. Results: Following dexmedetomidine injection in adult GAERS, initial absence status-like activity with duration of 128±13.74 min that abruptly converts to a sleep-anesthesia was triggered. When the 31.43±2.53 long sleep anesthesia was over, it abruptly switched to prolonged chain of SWDs in 100% of the animals. Atipamezole suppressed the prolonged seizure activities for 120 min and no activity above 1 min has been observed in the EEGs (p<0.01). SWDs with a duration of 10-16 sec still occurred with atipamezole. The mean duration at the 140th min of SWDs with atipamezole (15.2±3.8; n=4) was similar to the control groups of naïve GAERS: (14.2±1.8; n=4), which SWDs are expressed spontaneously. Conclusion: Activation of a2AR triggered a switch mechanism between prolonged SWDs, anesthesia sleep, and subsequent return to SWDs, but atipamezole recovered sleep activity as expected as well as absence status by removing two phase of events. This finding provides evidence that a2AR receptor targets may be the switch mechanism between the sleep and SWDs. [ABSTRACT FROM AUTHOR]

Objectives: Rho/Rho-kinase (ROCK) signaling has been shown to contribute to neuroinflammation, epileptogenesis, and seizures in convulsivetype epilepsy models. However, this pathway has not been investigated in the pathophysiology of absence epilepsy. The aim of this study was to investigate ROCK activity in brain regions involved in spike-and-wave discharge (SWD) generation and the effects of the Rho-kinase inhibitor, Y-27632, on ROCK activity in genetic absence epilepsy rats from Strasburg (GAERS). Methods: ROCK activity in the somatosensorial cortex, hippocampus, and thalamus was measured using an enzyme-linked immunosorbent assay (ELISA). An intracerebroventricular (i.c.v.) injection of Y-27632 was administered at a dose of 20 nmol/5 µl and changes in ROCK activity were assessed. To evaluate the effect of Y-27632 on SWDs, i.c.v. 20 nmol and 60 nmol doses of Y-27632 were administered to the GAERS subjects and electroencephalography was performed. Results: ROCK activity was elevated in the somatosensory cortex in the GAERS study subjects, and the Rho-kinase enzyme inhibitor, Y-27632, suppressed this increase. In addition, Y-27632 significantly reduced the total and mean duration of SWDs compared with the control group. Conclusion: The findings indicate that the Rho-kinase pathway may play a role in the generation of absence seizures, and that the suppressive effect of Y-27632 on SWDs may be a potential therapeutic target for this anti-absent effect. [ABSTRACT FROM AUTHOR]

Objective: 6-Hydroxydopamine (6-OHDA) is a toxic agent for the nigro-striatal dopaminergic neurons and it is used in modeling Parkinson's disease in rats (1). It is aimed to compare in genetic absence epilepsy rats (GAERS) and Wistar rats from Strasbourg, the apomorphine-induced rotation behavior, which is one of the indicators of dopaminergic damage of 6-OHDA toxicity. Methods: In this study, 30 days old Wistar and GAERS animals were divided into two groups. 6-OHDA(8 pg dose and 4 pL/4 minutes) was injected by stereotaxic surgery into the medial forebrain bundle (MFB) (AP: -1.4; ML: 1.6; V: 7.1 mm; single injection) of GAERS-MFB group (n=8), into the striatum (AP:-O.5/+O.5; ML:3.0; V: 5.0 mm; double injections) of GAERS-Striatum group (n=5), as well as into the MFB (AP:-1.4; ML: 1.6; V: 7.1 mm; single injection) of Wistar-MFB group (n=4) and the striatum (AP: -O.5/+O.5; ML: 3.0; V: 5.0 min; double injections) of Wistar-Striatum (n=2) group. After 21 days, all animals were injected with apomorphine (0.05 mg/kg, subcutan). After apomorphine administration, right and left rotation (3600) of the animals were recorded for 30 minutes. Data were expressed as mean+standart error. One-way ANOVA and Tukey post-hoc test were used (p<0.05 was considered significant). Results: The mean number of GAERS-MFB rotations was 6.56±0.05 per minute, whereas the GAERS-Striatum was 6.19±1.72 per minute. While the number of Wistar-MFB rotations was 4.74+2.33 per minute, the number of Wistar-Striatum rotations was 3.27±1.40 per minute. There was no statistically significant difference between the groups. Conclusion: Although the findings show there is no difference between the groups, it is aimed to continue the study by increasing the number because of the numbers of groups are limited in our study. The study is supported by TÜBİTAK (218S653). [ABSTRACT FROM AUTHOR]

Objective: Valproate is a well-recognized therapeutic choice in the management of epilepsies and manic episodes of bipolar disorders and has been associated with Parkinson-like symptoms, especially tremor, when used for long-term. Despite being reported as often resolved upon drug discontinuance, the symptoms might be permanent. This study aimed to determine whether a five-day administration of valproate resulted in the development of a Parkinsonism model in Wistar rats. Methods: Twice daily valproate 400 mg/kg were intraperitoneally injected to adult male Wistar rats (n=6) for five days. Locomotor, stepping, paw reaching, cylinder, and tremulous jaw movement tests were applied three days before the injection and at the end of the last valproate administration. Tremor data scoring is as follows: 0: no tremor, I: intermittent tremor, affecting only head and neck,II: intermittent tremor, affecting whole body, III: continuous tremor affecting whole body, tail, IV: continuous tremor Results: Tremulous jaw movement stage II and I occurred in 60% and 40% of rats, respectively; while no rats developed stage III or IV tremor upon 5-day course of valproate. There were sıgnificant reduction in total distance (%53.8 p<0.05), vertical and horizontal movements and in ambulatory time (%77.2, p<0.05; %48.64, p<0.05 and %52,3, p<0.05 respectively) compared to baseline in the locomotor activity test. While the number of stepping at the right side was significantly lower compared to the baseline (p<0.05). Cylinder test scores at minutes 0-2 significantly decreased in the right side by %93.4 and in the left side by %90,5 at the end of the study (p<0.05). Conclusion: The findings of the locomotor and cylinder tests imply that a five-day administration of valproate might elicit the development of a rat Parkinsonism model which appears to be substantially consistent with those in the literature. Our study, with dose and time modifications, can provide source for new researches. [ABSTRACT FROM AUTHOR]

Objective: The most common type of epilepsy affecting about 50 million people worldwide is temporal lobe epilepsy (TLE). Chemical and electrical kindling methods in animals can be used to form the TLE model. In this study, it was aimed to investigate neurogenesis by immunofluorescence methods in the hippocampus of adult Wistar rats, which were applied chemical kindling. Methods: Adult male Wistar albino rats weighing 250-300 gr were injected PTZ (35 mg/kg) subcutaneously every other day to produce chemical kindling (Wistar kindling 7th day group n=6; 14th day group n=6). Sham-operated control groups were injected physiological saline solution subcutaneously (Wistar shamoperated 7th day group n=6; 14th day group n=6). Animals having grade 5 seizures five times were considered to be kindled. Intracardiac perfusion was performed under deep anesthesia on the 7th and 14th days after the last grade 5 seizure. Then, the animals were decapitated and brain tissues were removed and incubated at 4°C overnight within the same fixative. The tissues were frozen at -80ºC and 5 μm sections were obtained with a cryomicrotome. Immunofluorescence methods were used to show doublecortin (DCX) positive newly formed neurons and glial fibrillary acidic protein (GFAP) positive cells. Sections were then examined under fluorescence microscope. Results: DCX positive cells were observed in the subgranular zone of gyrus dentatus in the control and kindling groups. An increase in GFAP positive cells in the kindling groups, compared to the control groups, was observed. Conclusion: The findings of the present study indicate the existence of neurogenesis in the control and kindled adult Wistar rats. The increase in GFAP positive cells in the kindling groups suggests astrogliosis. [ABSTRACT FROM AUTHOR]