-
Naunyn-Schmiedeberg's Archives of... Feb 2023General anesthetic drugs have been associated with various unwanted effects including an interference with mitochondrial function. We had previously observed increases...
General anesthetic drugs have been associated with various unwanted effects including an interference with mitochondrial function. We had previously observed increases of lactate formation in the mouse brain during anesthesia with volatile anesthetic agents. In the present work, we used mitochondria that were freshly isolated from mouse brain to test mitochondrial respiration and ATP synthesis in the presence of six common anesthetic drugs. The volatile anesthetics isoflurane, halothane, and (to a lesser extent) sevoflurane caused an inhibition of complex I of the electron transport chain in a dose-dependent manner. Significant effects were seen at concentrations that are reached under clinical conditions (< 0.5 mM). Pentobarbital and propofol also inhibited complex I but at concentrations that were two-fold higher than clinical EC values. Only propofol caused an inhibition of complex II. Complex IV respiration was not affected by either agent. Ketamine did not affect mitochondrial respiration. Similarly, all anesthetic agents except ketamine suppressed ATP production at high concentrations. Only halothane increased cytochrome c release indicating damage of the mitochondrial membrane. In summary, volatile general anesthetic agents as well as pentobarbital and propofol dose-dependently inhibit mitochondrial respiration. This action may contribute to depressive actions of the drugs in the brain.
Topics: Mice; Animals; Halothane; Ketamine; Propofol; Pentobarbital; Anesthetics, General; Isoflurane; Mitochondria; Electron Transport Complex I; Adenosine Triphosphate
PubMed: 36385685
DOI: 10.1007/s00210-022-02338-9 -
Journal of Ocular Pharmacology and... Mar 2022Anesthesia is necessary to conduct rodent electroretinograms (ERGs). We evaluated utility of the α2-agonist medetomidine versus xylazine for ERG studies in nondiabetic...
Anesthesia is necessary to conduct rodent electroretinograms (ERGs). We evaluated utility of the α2-agonist medetomidine versus xylazine for ERG studies in nondiabetic and diabetic rats. Pentobarbital was included as a comparator. Male Sprague-Dawley rats, with and without streptozotocin (STZ)-induced diabetes, were anesthetized with medetomidine (1 mg/kg), xylazine (10 mg/kg) (both with ketamine 75 mg/kg), or pentobarbital (70 mg/kg). The depth of anesthesia was assessed, and if adequate, scotopic ERGs were recorded. Blood glucose was monitored. In nondiabetic rats, all three agents induced satisfactory anesthesia, but with differing durations: medetomidine > pentobarbital > xylazine. ERG responses were similar under medetomidine and xylazine, but relatively reduced under pentobarbital. Both α2-agonists (but not pentobarbital) elicited marked hyperglycemia (peak values 316.1 ± 42.6 and 300.3 ± 29.5 mg/dL, respectively), persisting for 12 h. In diabetic rats, elevated blood glucose concentrations were not affected by any of the agents, but the depth of anesthesia under medetomidine and xylazine was inadequate for ERG recording. In nondiabetic rats, medetomidine and xylazine elicited comparable effects on ERGs that differ from pentobarbital, but both perturbed glucose metabolism, potentially confounding experimental outcomes. In STZ-diabetic rats, neither α2-agent provided adequate anesthesia, while pentobarbital did so. Problems with α2-anesthetic agents, including medetomidine, must be recognized to ensure meaningful interpretation of experimental results.
Topics: Adrenergic Agents; Anesthesia; Animals; Diabetes Mellitus, Experimental; Male; Medetomidine; Pentobarbital; Rats; Rats, Sprague-Dawley; Xylazine
PubMed: 34964655
DOI: 10.1089/jop.2021.0084 -
Journal of Neurophysiology Aug 2022Laryngeal function is vital to airway protection. Although swallow is mediated by the brainstem, the mechanism underlying the increased risk of dysphagia after cervical...
Laryngeal function is vital to airway protection. Although swallow is mediated by the brainstem, the mechanism underlying the increased risk of dysphagia after cervical spinal cord injury (SCI) is unknown. We hypothesized that: ) loss of descending phrenic drive affects swallow and breathing differently, and ) loss of ascending spinal afferent information alters swallow regulation. We recorded electromyograms (EMGs) from upper airway and chest wall muscles in freely breathing pentobarbital-anesthetized cats and rats. Laryngeal abductor activity during inspiration increased about twofold following C2 lateral hemisection. Ipsilateral to the injury, the crural diaphragm EMG amplitude was reduced during breathing (62 ± 25% change postinjury), but no animal had complete termination of activity; 75% of animals had increased contralateral diaphragm recruitment, but this did not reach significance. During swallow, laryngeal adductor and pharyngeal constrictor muscles increased activity, and diaphragm activity was bilaterally suppressed. This was unexpected because of the ipsilateral-specific response during breathing. Swallow-breathing coordination was disrupted by injury, and more swallows occurred during early expiration. Finally, to determine if the chest wall is a major source of feedback for laryngeal regulation, we performed T1 total transections in rats. As in the C2 lateral hemisection, inspiratory laryngeal recruitment was the first feature noted after injury. In contrast to the C2 lateral hemisection, diaphragmatic drive increased after T1 transection. Overall, we found that SCI alters laryngeal drive during swallow and breathing, and alters swallow-related diaphragm activity. Our results show behavior-specific effects, suggesting that swallow is affected more than breathing is by SCI, and emphasizing the need for additional studies on the effect of ascending afferents from the spinal cord on laryngeal function. This is the first manuscript to determine the impact of cSCI on laryngeal and swallow function, and to describe a possible mechanism for dysphagia and altered airway protection after injury.
Topics: Animals; Cervical Cord; Deglutition Disorders; Diaphragm; Phrenic Nerve; Rats; Rats, Sprague-Dawley; Spinal Cord; Spinal Cord Injuries
PubMed: 35830612
DOI: 10.1152/jn.00469.2021 -
Analytical Chemistry Oct 2022Barbiturates are highly susceptible to dissociation in mass spectrometry (MS) because of their long side chains combined with a nonaromatic ring consisting of several...
Barbiturates are highly susceptible to dissociation in mass spectrometry (MS) because of their long side chains combined with a nonaromatic ring consisting of several carbonyl and amine groups. As a result, they exhibit extensive α-cleavage and subsequent rearrangement, making the identification of these compounds difficult. Although a library of electron ionization MS (EIMS) is available, most barbiturates have very similar fragment patterns. Accordingly, it would be desirable to develop a technique for soft ionization, providing a molecular ion and large fragment ions as well. In this study, a molecular ion was clearly observed, in addition to large fragment ions, for a variety of barbiturates based on multiphoton ionization MS (MPIMS) using a tunable ultraviolet femtosecond laser as the ionization source (fs-LIMS). This favorable result was achieved when the optimal laser wavelength for minimizing the excess energy remaining in the ionic state was used. An examination of the photofragmentation pathways suggested that an H atom in the side chain was abstracted by an oxygen atom in the carbonyl group in the ring structure thus initiating fragmentation and subsequent rearrangement. Barbiturates that are substituted with alkyl groups (amobarbital and pentobarbital) had narrower spectral regions for optimal ionization than the other barbiturates with alkyl and alkenyl groups (butalbital and secobarbital) and more with alkyl and phenyl groups (phenobarbital). All of the barbiturates studied provided unique mass spectral patterns in fs-LIMS, which was useful for the reliable identification of these compounds in practical trace analysis.
Topics: Secobarbital; Amobarbital; Pentobarbital; Barbiturates; Phenobarbital; Mass Spectrometry; Ions; Oxygen; Amines
PubMed: 36229898
DOI: 10.1021/acs.analchem.2c03077 -
Frontiers in Endocrinology 2023The time of onset of puberty has been increasingly earlier, but its mechanism is still unclear. This study aimed to reveal the mechanism of leptin and NPY in the onset...
OBJECTIVES
The time of onset of puberty has been increasingly earlier, but its mechanism is still unclear. This study aimed to reveal the mechanism of leptin and NPY in the onset of puberty in male offspring rats after androgen intervention during pregnancy.
METHODS
Eight-week-old specific pathogen-free (SPF) healthy male Sprague-Dawley (SD) rats and 16 female SD rats were selected and caged at 1:2. The pregnant rats were randomly divided into the olive oil control group (OOG) and testosterone intervention group (TG), with 8 rats in each group. Olive oil and testosterone were injected from the 15th day of pregnancy, for a total of 4 injections (15th, 17th, 19th, 21st day). After the onset of puberty, the male offspring rats were anesthetized with 2% pentobarbital sodium to collect blood by ventral aorta puncture and decapitated to peel off the hypothalamus and abdominal fat. Serum testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA), sex hormone binding globulin (SHBG), and leptin were detected by ELISA, and then the free androgen index (FAI) was calculated. The mRNA levels of androgen receptor (AR), estrogen receptor α (ERα), NPY, leptinR, and NPY2R in the hypothalamus and abdominal fat were detected by RT-PCR. Protein expression levels of AR, ERα, NPY, leptinR, and NPY2R in the arcuate nucleus (ARC) of the hypothalamus were detected by immunohistochemistry.
RESULTS
The time of onset of puberty was significantly earlier in the TG than in the OOG ( 0.05) and was positively correlated with body weight, body length, abdominal fat, and leptinR mRNA levels in adipose tissue in the OOG ( 0.05), while it was positively correlated with serum DHT and DHEA concentrations and FAI and AR mRNA levels in the hypothalamus in the TG ( 0.05). The NPY2R mRNA level and protein expression levels of ERα, NPY2R, and leptinR in the TG were significantly higher than those in the OOG, while the protein expression levels of AR and NPY in the TG were significantly lower than those in the OOG ( 0.05).
CONCLUSIONS
Testosterone intervention during pregnancy led to an earlier onset of puberty in male offspring rats, which may render the male offspring rats more sensitive to androgens, leptin, and NPY at the onset of puberty.
Topics: Pregnancy; Rats; Male; Female; Animals; Androgens; Leptin; Estrogen Receptor alpha; Olive Oil; Rats, Sprague-Dawley; Sexual Maturation; Testosterone; Dihydrotestosterone; Dehydroepiandrosterone; RNA, Messenger
PubMed: 37056673
DOI: 10.3389/fendo.2023.1090552 -
Journal of Ethnopharmacology Oct 2023Although lettuce is traditionally known to have hypnotic and sedative effects, to date, only a few studies have documented its sleep-promoting effects and elucidated the...
ETHNOPHARMACOLOGICAL RELEVANCE
Although lettuce is traditionally known to have hypnotic and sedative effects, to date, only a few studies have documented its sleep-promoting effects and elucidated the related mechanisms.
AIM OF THE STUDY
We aimed to investigate the sleep-promoting activity of Heukharang lettuce leaf extract (HLE) with increased lactucin content, known as a sleep-promoting substance in lettuce, in animal models.
MATERIALS AND METHODS
To evaluate the effect of HLE on sleep behavior, analysis of electroencephalogram (EEG), gene expression of brain receptors, and activation mechanisms using antagonists were investigated in rodent models.
RESULTS
High-performance liquid chromatography analysis showed that HLE contained lactucin (0.78 mg/g of extract) and quercetin-3-glucuronide (1.3 mg/g of extract). In the pentobarbital-induced sleep model, the group administered 150 mg/kg of HLE showed a 47.3% increase in sleep duration time as compared to the normal group (NOR). The EEG analysis showed that the HLE significantly increased non-rapid eye movement (NREM), where delta waves were improved by 59.5% when compared to the NOR, resulting in increased sleep time. In the caffeine-induced arousal model, HLE significantly decreased the awake time increased by caffeine administration (35.5%) and showed a similar level to NOR. In addition, HLE increased the gene and protein expression of gamma-aminobutyric acid receptor type A (GABA), GABA type B, and 5-hydroxytryptamine (serotonin) receptor 1A. In particular, in comparison to the NOR, the group administered 150 mg/kg HLE showed an increase in expression levels of GABA and protein by 2.3 and 2.5 times, respectively. When the expression levels were checked using GABA receptor antagonists, HLE showed similar levels to NOR, as the sleep duration was reduced by flumazenil (45.1%), a benzodiazepine antagonist.
CONCLUSIONS
HLE increased NREM sleep and significantly improved sleep behavior due to its action on the GABA receptors. The collective findings suggest that HLE can be used as a novel sleep-enhancing agent in the pharmaceutical and food industries.
Topics: Animals; Receptors, GABA-A; Lactuca; Caffeine; Plant Extracts; Sleep; Hypnotics and Sedatives; gamma-Aminobutyric Acid
PubMed: 37149068
DOI: 10.1016/j.jep.2023.116602 -
Hospital Pharmacy Aug 2021Pentobarbital is a sedative agent to limit children motion during computed tomography or magnetic resonance imaging (MRI) and ensures the successful completion of the...
Pentobarbital is a sedative agent to limit children motion during computed tomography or magnetic resonance imaging (MRI) and ensures the successful completion of the imaging procedure. However, data on rectal drug formulation and its stability in practice are not available. The aim of this study was to formulate and evaluate the stability of a ready-to-use rectal pentobarbital gel. The formulation consisted of a hydrated gel containing 25 mg/mL of pentobarbital sodium, packaged in 10-mL amber glass bottles and stored at either 22°C to 25°C or 2°C to 8°C. At each predetermined time point, samples were taken for visual inspection, pH measurement, and analysis by a validated stability-indicating high-performance liquid chromatography (HPLC) method. The viscosity parameters of the hydrogel formulation were assessed. The freshly prepared rectal formulations appeared clear, colorless, and particular-free with pH readings of 9.75 to 9.83. Over the 90 days of the study period, there was no significant change in appearance or pH values for all stability samples. The HPLC results confirmed the chemical stability when stored at 2°C to 8°C or at 22°C to 25°C. Pentobarbital hydrogel 25 mg/mL are stable chemically at least 90 days and can be administered to children for an effective and fast sedation.
PubMed: 34381270
DOI: 10.1177/0018578719901276 -
Frontiers in Pharmacology 2021The interest in AMPA receptors as a target for epilepsy treatment increased substantially after the approval of perampanel, a negative AMPA receptor allosteric...
The interest in AMPA receptors as a target for epilepsy treatment increased substantially after the approval of perampanel, a negative AMPA receptor allosteric antagonist, for the treatment of partial-onset seizures and generalized tonic-clonic seizures. Here we performed a screening for activity against native calcium-permeable AMPA receptors (CP-AMPARs) and calcium-impermeable AMPA receptors (CI-AMPARs) among different anticonvulsants using the whole-cell patch-clamp method on isolated Wistar rat brain neurons. Lamotrigine, topiramate, levetiracetam, felbamate, carbamazepine, tiagabin, vigabatrin, zonisamide, and gabapentin in 100-µM concentration were practically inactive against both major subtypes of AMPARs, while phenytoin reversibly inhibited them with IC50 of 30 ± 4 μM and 250 ± 60 µM for CI-AMPARs and CP-AMPARs, respectively. The action of phenytoin on CI-AMPARs was attenuated in experiments with high agonist concentrations, in the presence of cyclothiazide and at pH 9.0. Features of phenytoin action matched those of the CI-AMPARs pore blocker pentobarbital, being different from classical competitive inhibitors, negative allosteric inhibitors, and CP-AMPARs selective channel blockers. Close 3D similarity between phenytoin and pentobarbital also suggests a common binding site in the pore and mechanism of inhibition. The main target for phenytoin in the brain, which is believed to underlie its anticonvulsant properties, are voltage-gated sodium channels. Here we have shown for the first time that phenytoin inhibits CI-AMPARs with similar potency. Thus, AMPAR inhibition by phenytoin may contribute to its anticonvulsant properties as well as its side effects.
PubMed: 34950035
DOI: 10.3389/fphar.2021.775040 -
Scientific Reports Jan 2020Rodents are widely used for animal research in Egypt. Pentobarbital is the most common anesthetic agent; however overdoses may affect the experimental outcomes and limit...
Rodents are widely used for animal research in Egypt. Pentobarbital is the most common anesthetic agent; however overdoses may affect the experimental outcomes and limit the use of tissues. To investigate the effects of sodium pentobarbital overdoses during exsanguination, three groups (6 rats/group) of male and female rats were injected i.p. with 50, 100 and 150 mg/kg of sodium pentobarbital, then carotid exsanguination was performed immediately after loss of consciousness. Hypoxia-inducible factor 1-alpha (Hif1a) and tumor necrosis factor-alpha (Tnfa) mRNA expressions in liver and kidney organs were evaluated. As well as, serum aminotransferase activities (AST&ALT), glucose, urea, creatinine, malondialdehyde (MDA), reduced glutathione (GSH) and catalase (CAT) levels were determined. The histological alterations in liver, kidney and spleen were studied. It was found that Hif1a and Tnfa were significantly overexpressed in the studied organs and serum AST, glucose, creatinine and urea levels were significantly increased after sodium pentobarbital overdoses (100 and 150 mg/kg) compared to 50 mg/kg dose. Similarly, significant increase in MDA and GSH levels of liver, kidney and spleen were noticed. Results showed gender difference where Hif1a and Tnfa levels were significantly overexpressed at high dose of sodium pentobarbital of liver and kidney organs in female more than male rats. Since euthanasia protocol may influence the physiological variables and affect genes' expression, it is recommended to avoid sodium pentobarbital overdose during euthanasia as it may interfere with the biochemical, molecular and histological measurements.
Topics: Adjuvants, Anesthesia; Animals; Biomarkers; Exsanguination; Female; Glutathione; Kidney; Liver; Liver Function Tests; Male; Malondialdehyde; Oxidative Stress; Pentobarbital; Rats; Rats, Wistar
PubMed: 31942001
DOI: 10.1038/s41598-019-57252-7 -
Pharmaceutics Feb 2023Pentobarbital is a drug of choice to limit motion in children during paediatric procedural sedations (PPSs). However, despite the rectal route being preferred for...
Pentobarbital is a drug of choice to limit motion in children during paediatric procedural sedations (PPSs). However, despite the rectal route being preferred for infants and children, no pentobarbital suppositories are marketed, and therefore they must be prepared by compounding pharmacies. In this study, two suppository formulations of 30, 40, 50, and 60 mg of pentobarbital sodium were developed using hard-fat Witepsol W25 either alone (formulation F1) or with oleic acid (formulation F2). The two formulations were subjected to the following tests described in the European Pharmacopoeia: uniformity of dosage units, softening time, resistance to rupture, and disintegration time. The stability of both formulations was also investigated for 41 weeks of storage at 5 ± 3 °C using a stability-indicating liquid chromatography method to quantify pentobarbital sodium and research breakdown product (BP). Although both formulae were compliant to uniformity of dosage, the results were in favour of a faster disintegration of F2 compared to F1 (-63%). On the other hand, F1 was found to be stable after 41 weeks of storage unlike F2 for which several new peaks were detected during the chromatographic analysis, suggesting a shorter stability of only 28 weeks. Both formulae still need to be clinically investigated to confirm their safety and efficiency for PPS.
PubMed: 36986615
DOI: 10.3390/pharmaceutics15030755