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| Schematic diagram of the timeline of the testosterone supplementation in non-castrated and castrated rats.
Source publication
Testosterone is responsible for several changes in the brain, including behavioral and emotional responses, memory, and cognition. Given this, we investigated changes in the brain wave profile caused by supplementation with exogenous testosterone in both castrated and non-castrated rats. We also investigated the serum testosterone levels, renal and...
Contexts in source publication
Context 1
... present study was based on two separate experiments, with an identical design. The only difference in the experimental designs was in the final evaluation, with that of Experiment I being based on ECoG recordings, whereas in Experiment II the animals were assessed in an elevated plus-maze (EPM), open field test (OFT), agonistic encounters with an intruder male, and biochemical and hormonal analyses (Figure 1). The orchiectomized and sham animals (12 weeks old) were operated 2 weeks before the start of the experimental protocol to reduce the levels of circulating TST from testicular secretions in the castrated animals. ...
Context 2
... animals were assessed 24 h after the final injection (Figure 1), according to the experiment, with the collection of electrocorticographic records in the case of Experiment I and behavioral and biochemical analyses in the case of Experiment II. The body weight of each animal was obtained daily in order to calculate the injection volume required to administer the desired dose. ...
Citations
... The following protocols were established following the procedures described by Hamoy et al. (2018), Estumano et al. (2019), Muto et al. (2021) and Bastos de Araújo et al. (2023). The animals were anesthetized with a combination of xylazine hydrochloride (5 mg/kg) and ketamine hydrochloride (100 mg/kg) via intraperitoneal injection. ...
Alcohol, a widely commercialized psychotropic drug, and the benzodiazepine Flunitrazepam, an anxiolytic widely prescribed for patients with anxiety and insomnia problems, are well known drugs and both act on the central nervous system. The misuse and the association of these two drugs are public health concerns in several countries and could cause momentary, long-lasting and even lethal neurophysiological problems due to the potentiation of their adverse effects in synergy. The present study observed the result of the association of these drugs on electrophysiological responses in the brain, heart, and respiratory rate in Wistar rats. 8 experimental groups were determined: control, one alcohol group (20% at a dose of 1 ml/100 g VO), three Flunitrazepam groups (doses 0.1; 0.2 and 0.3 mg/kg) and three alcohol-Flunitrazepam groups (20% at a dose of 1 ml/100 g VO of alcohol, combined with 0.1; 0.2 and 0.3 mg/kg of Flunitrazepam, respectively). The results showed that there was a more pronounced reduction in alpha and theta wave power in the alcohol-Flunitrazepam groups, a decrease in the power of beta oscillations and greater sedation. There was a progressive decrease in respiratory rate linked to the increase of Flunitrazepam dose in the alcohol-Flunitrazepam associated administration. It was observed alteration in heart rate and Q-T interval in high doses of Flunitrazepam. Therefore, we conclude that the association alcohol-Flunitrazepam presented deepening of depressant synergistic effects according to the increase in the dose of the benzodiazepine, and this could cause alterations in low frequency brain oscillations, breathing, and hemodynamics of the patient.
... The variations in power intensities in brain oscillations can be caused by the use of drugs [38,39], like hormonal disorders and testosterone replacement therapy [40]. Studies on alpha rhythm show that increased amplitude in the alpha is related to somatization severity observed in patients after accounting for the influence of anxiety and depression [41,42]. ...
... The increase in beta potency is related to the aggressive behaviour observed in the animal, due to activity observed in the thalamic and cortical regions [40,59,60]. According to our data, the increase in the potency of the beta oscillations may be related to the decrease in the seizure threshold since, after the application of PTZ, there was an increase in the recorded potency for the groups that received Tadalafil and Sildenafil in advance. ...
Background
Phosphodiesterase 5 inhibitors (PDE5i) are the first line treatment for erectile dysfunction; however, several articles and case reports have shown central nervous system effects, that can cause seizures in susceptible patients. This study aims to describe the changes caused by the use of Sildenafil and Tadalafil through the analysis of abnormalities expressed in the electrocorticogram (ECoG) of rats and evaluate the seizure threshold response and treatment of seizures with anticonvulsants.
Materials and methods
The study used 108 rats (Wistar). Before surgery for electrode placement in dura mater, the animals were randomly separated into 3 experiments for electrocorticogram analysis. Experiment 1: ECoG response to using PD5i (Sildenafil 20mg/kg and Tadalafil 2.6mg/kg p.o.). Experiment 2: ECoG response to the use of PD5i in association with Pentylenetetrazole (PTZ—30 mg/kg i.p.), a convulsive model. Experiment 3: ECoG response to anticonvulsant treatment (Phenytoin, Phenobarbital and Diazepam) of seizures induced by association IPDE5 + PTZ. All recordings were made thirty minutes after administration of the medication and analyzed for ten minutes, only once. We considered statistical significance level of *p<0.05, **p<0.01 and ***p < 0.001.
Results
After administration of Sildenafil and Tadalafil, there were increases in the power of recordings in the frequency bands in oscillations in alpha (p = 0.0920) and beta (p = 0.602) when compared to the control group (p<0.001). After the use of Sildenafil and Tadalafil associated with PTZ, greater potency was observed in the recordings during seizures (p<0.001), however, the Sildenafil group showed greater potency when compared to Tadalafil (p<0.05). Phenobarbital and Diazepam showed a better response in controlling discharges triggered by the association between proconvulsant drugs.
Conclusions
PDE5i altered the ECoG recordings in the rats’ motor cortexes, demonstrating cerebral asynchrony and potentiating the action of PTZ. These findings demonstrate that PDE5i can lower the seizure threshold.
... The EEGs were recorded as described by Estumano et al. (2019). For this, the animals were anesthetized and placed in a stereotaxic apparatus for the implantation of stainless-steel electrodes (exposed tip 1.0 mm in diameter) on the dura mater above the pre-frontal cortex at the bregma coordinates − 0.96 mm and ± 1.0 mm lateral, and were fixed with dental acrylic cement. ...
Epilepsy is one of the most common neurological disorders, which occurs due to the instability in the inhibitory and excitatory synaptic transmissions in the brain. However, many patients develop resistance to the available drugs, which results in cell degeneration caused due to inadequate control of the seizures. Curcumin, Curcuma longa, is known to be effective for the treatment of organic disorders and may prevent seizures, reduce oxidative stress, and decrease brain damage. Given this, the present study evaluated the antiepileptic effects of C. longa in comparison with both the diazepam and the combined application of these two substances, in terms of their effects on the brain activity and the potential histopathological changes in the hippocampus. This study used male Wistar rats (age: 10-12 weeks; weight: 260 ± 20 g), which were pretreated for 4 days with either saline, C. longa, diazepam, or C. longa + diazepam; and on the fifth day, pentylenetetrazol (PTZ) was administered to induce the seizure. In the C. longa group, a significant increase was observed in the latency of the onset of seizure-related behavior. Surprisingly, however, the combined treatment resulted in the best control of the seizure-related behavior, with the greatest latency of the onset of spasms and isolated clonic seizures. This group also obtained the best results in the electroencephalographic trace and seizure control, with a reduction in the frequency and amplitude of the spike-waves. In the saline group, PTZ significantly reduced the number of cells present in the CA1 and CA3 regions of the hippocampus, while the combined treatment obtained the best results in terms of the preservation of the neuron-like cells. These findings indicate that C. longa may contribute to the control of both seizures and the cell damage induced by PTZ, and that its association with diazepam may be a potentially effective option for the treatment of epilepsy in the future.
... The ECoG recordings were obtained following the procedure described by Estumano et al. (20). For this, the animals were first anesthetized with ketamine (50 mg/kg, ip) and xylazine (10 mg/kg, ip). ...
Seizures are a disorder caused by structural brain lesions, life-threatening metabolic derangements, or drug toxicity. Thepresent study describes the behavior related to proconvulsant activity induced by thiocolchicoside (TCC) in rats andinvestigates the electrocorticographic patterns of this behavior and the effectiveness of classic antiepileptic drugs used tocontrol these seizures. Forty-nine adult male Wistar rats were used and divided into two phases of our experimental design:1) evaluation of seizure-related behavior and electrocorticographic patterns induced by TCC and 2) evaluation of the efficacy ofclassical antiepileptic drugs to control the proconvulsive activity caused by TCC. Our results showed that TCC induced tonic-clonic seizures that caused changes in electrocorticographic readings, characteristic of convulsive activity, with averageamplitude greater than that induced by pentylenetetrazole. Treatment with anticonvulsants, especially diazepam, reduced theelectrocorticographic outbreaks induced by TCC. The results suggested that TCC caused seizures with increased power inbrain oscillations up to 40 Hz and that diazepam may partially reverse the effects.
... The ECoG recordings were obtained following the procedure described by Estumano et al. (20). For this, the animals were first anesthetized with ketamine (50 mg/kg, ip) and xylazine (10 mg/kg, ip). ...
Seizures are a disorder caused by structural brain lesions, life-threatening metabolic derangements, or drug toxicity. The present study describes the behavior related to proconvulsant activity induced by thiocolchicoside (TCC) in rats and investigates the electrocorticographic patterns of this behavior and the effectiveness of classic antiepileptic drugs used to control these seizures. Forty-nine adult male Wistar rats were used and divided into two phases of our experimental design: 1) evaluation of seizure-related behavior and electrocorticographic patterns induced by TCC and 2) evaluation of the efficacy of classical antiepileptic drugs to control the proconvulsive activity caused by TCC. Our results showed that TCC induced tonic-clonic seizures that caused changes in electrocorticographic readings, characteristic of convulsive activity, with average amplitude greater than that induced by pentylenetetrazole. Treatment with anticonvulsants, especially diazepam, reduced the electrocorticographic outbreaks induced by TCC. The results suggested that TCC caused seizures with increased power in brain oscillations up to 40 Hz and that diazepam may partially reverse the effects.
... No 5º dia após a cirurgia, os eletrodos foram conectados a um sistema de aqui sição de dados composto por um amplificador de alta impedância (P511, Grass Technologies), monitorado com osciloscópio (Protek, 6510). (12) A administração intraperitoneal de cafeína foi realizada 15 minutos antes do registro. Os dados foram digitalizados de forma contínua a uma frequência de 1kHz, por meio de com putador equipado com placa de aquisição de dados (National Instruments, Austin, TX, Estados Unidos). ...
Objective:
To describe electrocorticographic, electromyographic and electrocardiographic profiles to report the electrophysiological effects of caffeine in Wistar rats.
Methods:
Male adult Wistar rats weighing 230g to 250g were used. Rats were allocated to one of two groups, as follows: Group 1, Control, intraperitoneal injection of 0.9% saline solution (n=27); and Group 2, treated with intraperitoneal injection of caffeine (50mg/kg; n=27). The rats were submitted to electrocorticographic, electromyographic and electrocardiographic assessment.
Results:
Brain oscillations (delta, theta, alpha, beta and gamma) in the frequency range up to 40Hz varied after caffeine administration to rats. Powers in delta and theta oscillations ranges were preponderant. The contractile force of the skeletal striated and cardiac muscles increased. Electrocardiogram analysis revealed shorter RR, QRS and QT intervals under the effect of caffeine.
Conclusion:
In the central nervous system, there was an increase in the delta, theta and alpha amplitude spectrum, which are related to memory encoding and enhanced learning. With regard to skeletal muscle, increased contraction of the gastrocnemius muscle was demonstrated, a clear indication of how caffeine can be used to enhance performance of some physical activities. Electrocardiographic changes observed after caffeine administration are primarily related to increased heart rate and energy consumption.
... The ECoG recordings were obtained using the procedures described by Estumano et al. (2019). For this, the animals were anesthetized with ketamine hydrochloride (80 mg/kg, i.p.) and xylazine hydrochloride (10 mg/kg, i.p.), and after the abolishment of their corneal reflex, they were placed in a stereotaxic apparatus. ...
Introduction
Local anesthetics are widely used in clinical practice. While toxicity is rare, these drugs can cause potentially lethal seizures.
Objective
In the present study, we investigated the electrocorticographic (ECoG) and electromyographic patterns of seizures induced by acute lidocaine (LA) toxicity and treated with anticonvulsant drugs. The study used adult male Wistar rats to describe of the seizure‐related behavior of LA and investigated the treatment with anticonvulsant drugs.
Results
The use of LA resulted in clear changes in the ECoG pattern, which presented characteristics of Status epilepticus, with increased intensity in all brainwaves. The decomposition of the cerebral waves showed an increase in the beta and gamma waves that may be related to tonic–clonic seizure. Although the treatment with anticonvulsants drugs reduces the power of brainwaves at frequencies between 1 and 40 Hz compared to the LA group, but only diazepam (DZP) was able to decrease the intensity of oscillations. The muscle contraction power also indicated a difference in the effectiveness of the three treatments.
Conclusion
The sum of the evidence indicates that LA causes status epilepticus and that DZP is the most effective treatment for the control of these seizures, by restoring the systemic values to levels close to those recorded in the control group.
... Latency to the seizure was recorded and behavioral modifications were classified in four clinically-identifiable Electrocorticographic recordings and data analyses. The ECoG recordings and offline data analyses followed the procedures described by Estumano et al. 31 . The animals were first anesthetized with ketamine hydrochloride (80 mg/kg, i.p.) and xylazine hydrochloride (10 mg/kg, i.p), and once the corneal reflex had been abolished, they were placed in a stereotaxic apparatus and stainless steel electrodes (1.0 mm diameter tip exposure) were placed on the duramater at the coordinates of the bregma-0.96 ...
... Five days after surgery, the ECoGs were obtained using a digital data acquisition system and the offline analyses were conducted. The analyses were run at a frequency of up to 50 Hz, and split into bands as in Estumano et al. 31 , that is, delta (1-4 Hz), theta (4-8 Hz), alpha (8)(9)(10)(11)(12), beta (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28), and gamma (28-40 Hz), for interpretation of the wave dynamics during the development of the seizure. The recordings followed a predefined protocol: the animals were immobilized carefully for 10 min for habituation, to avoid interference in the records. ...
Camphor is an aromatic terpene compound found in the essential oils of many plants, which has been used for centuries as a herbal medicine, especially in children. However, many studies have shown that camphor may have major side effects, including neurological manifestation, such as seizures. In the present study, we investigated the electrocorticographic patterns of seizures induced by camphor in male adult Wistar rats. Each rat received 400 mg/kg (i.p.) of camphor prior to monitoring by electrocorticography. The application of camphor resulted a rapid evolution to seizure and marked changes in the electrocorticographic readings, which presented characteristics of epileptiform activity, with an increase in the total power wave. The decomposition of the cerebral waves revealed an increase in the delta and theta waves. The analysis of the camphor traces revealed severe ictal activity marked by an increase in the polyspike wave. Our data thus indicate that camphor may cause seizures, leading to tonic–clonic seizures. Clearly, further studies are necessary to better elucidate the mechanisms through which camphor acts on the brain, and to propose potential treatments with anticonvulsant drugs that are effective for the control of the seizures.
High testosterone hormone levels play an important role in exhibiting aggressive behaviour and several disorders in female rodents and women. The present study aimed to determine the protective role of the alcoholic extract of Mentha spicata leaves (MSL) in the reduction of the level of testosterone and aggressive behaviour of female rats that suffer from high levels of testosterone. A total of 30 female Wistar albino rats were divided into 6 Groups. Group 1: Control rats received sesame oil(0.5 ml). Group 2: Rats injected with testosterone propionate (TP) alone. Group 3: Rats received MSL alone (100 mg/kg) orally. Groups 4, 5, and 6: Rats received TP + MSL, 6mg/rat of TP followed by 200, 400, and 600 mg/rat, respectively) for 60 days. The testosterone, dopamine, and aggressive behaviour were measured using specialized ELISA test kits. The results showed that testosterone and dopamine levels in the serum had a significant decrease (P<0.05) (4.82 (ng/ml) in testosterone and 272.83 (pg/ml) in dopamine) in animals treated with MSL only compared to Group 2, which found a significant rise (p<0.05) (16.52 (ng/ml) in testosterone and 607.59 (pg/ml) in dopamine) in the levels of testosterone and dopamine. The results exhibited a significant rise (P<0.05) in the aggressive behaviour in Group 2 of rats compared to the control and other Groups. In comparison, aggressive behaviour was significantly decreased (P<0.05) (7.40 (ng/ml) in testosterone and 263.49 (ng/ml) in dopamine) in Groups 2, 4, 5, and 6. Thus, the study revealed the protective role of the alcoholic extract of MSL in reducing levels of testosterone and aggressive behaviour in female rats suffering from higher levels of testosterone.
Low plasma levels of vitamin D causes bone mineral change that can precipitate osteopenia and osteoporosis, and could aggravate autoimmune diseases, hypertension and diabetes. The demand for vitamin D supplementation becomes necessary; however, the consumption of vitamin D is not without risks, which its toxicity could have potentially serious consequences related to hypervitaminosis D, such as hypercalcemia and cerebral alterations. Thus, the present study describes the electroencephalographic changes caused by supraphysiological doses of vitamin D in the brain electrical dynamics, and the electrocardiographic changes. After 4 days of treatment with vitamin D at dose of 25,000 IU/Kg, the serum calcium levels found was increased in comparison with control group. The ECoG analysis found a reduction in wave activity in the delta, theta, alpha and beta frequency bands. For ECG was observed changes with shortened QT follow-up, which could be related to serum calcium concentration. This study presented important evidence about the cerebral and cardiac alterations caused by high doses of vitamin D, indicating valuable parameters in the screening and decision-making process for diagnosing patients with symptoms suggestive of intoxication.
