Simulated validation of intron-less transgene detection using DELLY for gene-doping control in horse sports.

Gene doping is prohibited in horseracing. In a previous study, we developed a method for non-targeted transgene detection using DELLY, which is based on split-read (SR) and paired-end (PE) algorithms to detect structural variants, on WGS data. In this study, we validated the detection sensitivity of DELLY using artificially generated sequence data of 12 target genes. With DELLY, at least one intron was detected as a deletion in eight targeted genes using the 150 bp PE read WGS data, whereas all targeted genes were detected by DELLY using the 100 bp PE read data. The detection sensitivity was higher in 100 bp PE reads than in 150 bp PE reads, despite a lower total sequence coverage, probably because of mismatch tolerance between the mapped reads and reference genome. In addition, it was observed that the average intron size detected by SR alone was 293 bp and that that detected by both SR and PE was 8924 bp. Thus, we showed that transgenes with various intron-exon structures could be detected using DELLY, suggesting its application in gene-doping control in horses.

An experimental setup for creating and imaging 4He2 * excimer cluster tracers in superfluid helium-4 via neutron-3He absorption reaction.

For the purpose of future visualization of the flow field in superfluid helium-4, clusters of the triplet state excimer 4He2 * are generated along the micro-scale recoil tracks of the neutron-absorption reaction n + 3He → 3T + p. This reaction is induced by neutron irradiation of the 3He fraction contained in natural isotopic abundance liquid helium with neutron beams either from the Japan Proton Accelerator Research Complex, Materials and Life Science Experimental Facility (JPARC)/Materials and Life Science Experimental Facility or from the Kyoto University Institute for Integrated Radiation and Nuclear Science. These 4He2 * clusters are expected to be ideal tracers of the normal-fluid component in superfluid helium with several advantageous properties. Evidence of the excimer generation is inferred by detection of laser induced fluorescence emitted from the 4He2 * clusters excited by a purpose-built short pulse gain-switched titanium:sapphire (Ti:sa) laser operating at a wavelength of 905 nm. The setup and performance characteristics of the laser system including the Ti:sa and two continuous wave re-pumping lasers are described. Detection at the fluorescence wavelength of 640 nm is performed by using optical bandpass filtered photomultiplier tubes (PMT). Electrical noise in the PMT acquisition traces could successfully be suppressed by post-processing with a simple algorithm. Despite other laser-related backgrounds, the excimer was clearly identified by its fluorescence decay characteristics. Production of the excimer was found to be proportional to the neutron flux, adjusted via insertion of different collimators into the neutron beam. These observations suggest that the apparatus we constructed does function in the expected manner and, therefore, has the potential for groundbreaking turbulence research with superfluid helium.

A candidate-SNP retrospective cohort study for fracture risk in Japanese Thoroughbred racehorses.

Fractures are medical conditions that compromise the athletic potential of horses and/or the safety of jockeys. Therefore, the reduction of fracture risk is an important horse and human welfare issue. The present study used molecular genetic approaches to determine the effect of genetic risk for fracture at four candidate SNPs spanning the myostatin (MSTN) gene on horse chromosome 18. Among the 3706 Japanese Thoroughbred racehorses, 1089 (29.4%) had experienced fractures in their athletic life, indicating the common occurrence of this injury in Thoroughbreds. In the case/control association study, fractures of the carpus (carpal bones and distal radius) were statistically associated with g.65809482T/C (P = 1.17 x 10-8 ), g.65868604G/T (P = 2.66 x 10-9 ), and g.66493737C/T (P = 6.41 x 10-8 ). In the retrospective cohort study using 1710 racehorses born in 2000, the relative risk (RR) was highest for male horses at g.65868604G/T, based on the dominant allele risk model (RR = 2.251, 95% confidence interval 1.407-3.604, P = 0.00041), and for female horses at g.65868604G/T, based on the recessive allele risk model (RR = 2.313, 95% confidence interval 1.380-3.877, P = 0.00163). Considering the association of these SNPs with racing performance traits such as speed, these genotypes may affect the occurrence of carpus fractures in Japanese Thoroughbred racehorses as a consequence of the non-genetic influence of the genotype on the distance and/or intensity of racing and training. The genetic information presented here may contribute to the development of strategic training programs and racing plans for racehorses that improve their health and welfare.

Genetic diversity and relationships among native Japanese horse breeds, the Japanese Thoroughbred and horses outside of Japan using genome-wide SNP data.

Eight horse breeds-Hokkaido, Kiso, Misaki, Noma, Taishu, Tokara, Miyako and Yonaguni-are native to Japan. Although Japanese native breeds are believed to have originated from ancient Mongolian horses imported from the Korean Peninsula, the phylogenetic relationships among these breeds are not well elucidated. In the present study, we compared genetic diversity among 32 international horse breeds previously evaluated by the Equine Genetic Diversity Consortium, the eight Japanese native breeds and Japanese Thoroughbreds using genome-wide SNP genotype data. The proportion of polymorphic loci and expected heterozygosity showed that the native Japanese breeds, with the exception of the Hokkaido, have relatively low diversity compared to the other breeds sampled. Phylogenetic and cluster analyses demonstrated relationships among the breeds that largely reflect their geographic distribution in Japan. Based on these data, we suggest that Japanese horses originated from Mongolian horses migrating through the Korean Peninsula. The Japanese Thoroughbreds were distinct from the native breeds, and although they maintain similar overall diversity as Thoroughbreds from outside Japan, they also show evidence of uniqueness relative to the other Thoroughbred samples. This is the first study to place the eight native Japanese breeds and Japanese Thoroughbred in context with an international sample of diverse breeds.

Layer thickness dependence of the terahertz emission based on spin current in ferromagnetic heterostructures.

The emission with a bandwidth of 1.5 terahertz based on the spin current in the ferromagnetic heterostructure Co/Pt is demonstrated. The spin transient launched by the NIR femtosecond laser pulse in the Co/Pt is converted into the in-plane charge current due to the inverse spin Hall effect, which gives rise to the terahertz emission towards free space. The dependence of the terahertz emission on the Pt-layer thickness is investigated. To optimize the geometry structure of the new type of emitter, we developed the theoretical model by carefully analyzing the spin transport. Our model reveals the importance to take into account the interfacial spin loss. It can be used to analyze more complex heterostructures.

Perioperative respiratory complications: current evidence and strategy discussed in 2017 JA symposium.

Respiratory management during general anesthesia aims to safely secure the airway and maintain adequate ventilation to deliver oxygen to the vital organs, maintaining homeostasis even during surgery. Despite its clinical importance, anesthesiologists often encounter difficulties in properly managing respiration during the perioperative period, leading to severe respiratory complications. In this year's JA symposium, 5 editorial board members of Journal of Anesthesia (JA) who are experts in the field of respiratory management in anesthesia discussed the following topics: quitting smoking before surgery: exposure to passive smoke is damaging to children, ventilator-associated pneumonia, high inspiratory oxygen concentration and lung injury, aspiration pneumonia, and postoperative respiratory management strategy in patients with obstructive sleep apnea. We hope that this special article regarding this year's JA symposium may be useful for JA readers to manage clinical anesthesia on a daily basis.

Novel reuterin-related compounds suppress odour by periodontopathic bacteria.

OBJECTIVE: Halitosis is caused by volatile sulphur compounds including methyl mercaptan (CH3 SH) in the oral cavity and is a serious problem that limits interpersonal social communication. The aim of study was to evaluate the effects of reuterin-related compounds (RRCs) on halitosis-related periodontopathic bacteria in vitro. MATERIALS AND METHODS: RRC-01, RRC-02 and RRC-03 (32 and 64 µg ml-1 ) in culture media containing Fusobacterium nucleatum JCM8523 and Porphyromonas gingivalis ATCC33277 were used. The effects of RRCs on CH3 SH production and detectable odour by F. nucleatum and P. gingivalis were examined by CH3 SH production assay and organoleptic test, respectively. The number of bacterial cells was also measured using an ATP assay. In P. gingivalis treated with RRCs, the expression of mgl gene, which is responsible for CH3 SH production, was examined by qRT-PCR. RESULTS: CH3 SH production and the score of detectable odour from F. nucleatum and P. gingivalis culture media containing RRCs were significantly lower than that without RRCs (P < 0.05). The expression of mgl gene in P. gingivalis was significantly downregulated by RRC-01 (P < 0.01), but not by RRC-02 or RRC-03. CONCLUSIONS: RRCs are potent oral care products for preventing halitosis via reducing CH3 SH production.

Pathogenic factors in Candida biofilm-related infectious diseases.

Candida albicans is a commonly found member of the human microflora and is a major human opportunistic fungal pathogen. A perturbation of the microbiome can lead to infectious diseases caused by various micro-organisms, including C. albicans. Moreover, the interactions between C. albicans and bacteria are considered to play critical roles in human health. The major biological feature of C. albicans, which impacts human health, resides in its ability to form biofilms. In particular, the extracellular matrix (ECM) of Candida biofilm plays a multifaceted role and therefore may be considered as a highly attractive target to combat biofilm-related infectious diseases. In addition, extracellular DNA (eDNA) also plays a crucial role in Candida biofilm formation and its structural integrity and induces the morphological transition from yeast to the hyphal growth form during C. albicans biofilm development. This review focuses on pathogenic factors such as eDNA in Candida biofilm formation and its ECM production and provides meaningful information for future studies to develop a novel strategy to battle infectious diseases elicited by Candida-formed biofilm.

Evaluation of the effectiveness of the potent bis-quaternary ammonium compound, 4,4'-(α,ω-hexametylenedithio) bis (1-octylpyridinium bromide) (4DTBP-6,8) on Pseudomonas aeruginosa.

AIMS: Quaternary ammonium compounds (QACs), including benzalkonium chloride (BAC) and cetylpyridinium chloride (CPC) are cationic surfactants and have been used widely as general disinfectants in the medical field due to their strong antibacterial effects and low cytotoxicity to human cells. 4,4'-(α,ω-hexametylenedithio) bis (1-octylpyridinium bromide) (4DTBP-6,8) is one of the potent bis-QACs synthesized to improve the antimicrobial activities of mono-QACs such as BAC. This study aimed to assess the effectiveness of 4DTBP-6,8 against Pseudomonas aeruginosa, a prevalent hospital pathogen. METHODS AND RESULTS: The minimum inhibitory concentrations of 4DTBP-6,8, CPC and BAC against P. aeruginosa were measured. 4DTBP-6,8 exhibited strong antibacterial activity. We assessed the bactericidal effects of QACs against P. aeruginosa under certain conditions and their cytotoxicities in human epithelial cells using lactate dehydrogenase (LDH) release. 4DTBP-6,8 exerted excellent bactericidal effects against high concentrations of bacteria, biofilm cells and even in the presence of contaminated proteins. Cellular LDH was not released by the treatment with 4DTBP-6,8. CONCLUSIONS: 4DTBP-6,8 exhibited the strongest bactericidal activity against P. aeruginosa among the three QACs tested without any cytotoxicity. SIGNIFICANCE AND IMPACT OF THE STUDY: The potent bis-QAC, 4DTBP-6,8 has the potential to be an effective disinfectant in preventing hospital infections caused by P. aeruginosa.

Rad18 and Rnf8 facilitate homologous recombination by two distinct mechanisms, promoting Rad51 focus formation and suppressing the toxic effect of nonhomologous end joining.

The E2 ubiquitin conjugating enzyme Ubc13 and the E3 ubiquitin ligases Rad18 and Rnf8 promote homologous recombination (HR)-mediated double-strand break (DSB) repair by enhancing polymerization of the Rad51 recombinase at γ-ray-induced DSB sites. To analyze functional interactions between the three enzymes, we created RAD18(-/-), RNF8(-/-), RAD18(-/-)/RNF8(-/-) and UBC13(-/-)clones in chicken DT40 cells. To assess the capability of HR, we measured the cellular sensitivity to camptothecin (topoisomerase I poison) and olaparib (poly(ADP ribose)polymerase inhibitor) because these chemotherapeutic agents induce DSBs during DNA replication, which are repaired exclusively by HR. RAD18(-/-), RNF8(-/-) and RAD18(-/-)/RNF8(-/-) clones showed very similar levels of hypersensitivity, indicating that Rad18 and Rnf8 operate in the same pathway in the promotion of HR. Although these three mutants show less prominent defects in the formation of Rad51 foci than UBC13(-/-)cells, they are more sensitive to camptothecin and olaparib than UBC13(-/-)cells. Thus, Rad18 and Rnf8 promote HR-dependent repair in a manner distinct from Ubc13. Remarkably, deletion of Ku70, a protein essential for nonhomologous end joining (NHEJ) significantly restored tolerance of RAD18(-/-) and RNF8(-/-) cells to camptothecin and olaparib without affecting Rad51 focus formation. Thus, in cellular tolerance to the chemotherapeutic agents, the two enzymes collaboratively promote DSB repair by HR by suppressing the toxic effect of NHEJ on HR rather than enhancing Rad51 focus formation. In contrast, following exposure to γ-rays, RAD18(-/-), RNF8(-/-), RAD18(-/-)/RNF8(-/-) and UBC13(-/-)cells showed close correlation between cellular survival and Rad51 focus formation at DSB sites. In summary, the current study reveals that Rad18 and Rnf8 facilitate HR by two distinct mechanisms: suppression of the toxic effect of NHEJ on HR during DNA replication and the promotion of Rad51 focus formation at radiotherapy-induced DSB sites.

Aberrant IDH3α expression promotes malignant tumor growth by inducing HIF-1-mediated metabolic reprogramming and angiogenesis.

Cancer cells gain a growth advantage through the so-called Warburg effect by shifting glucose metabolism from oxidative phosphorylation to aerobic glycolysis. Hypoxia-inducible factor 1 (HIF-1) has been suggested to function in metabolic reprogramming; however, the underlying mechanism has not been fully elucidated. We found that the aberrant expression of wild-type isocitrate dehydrogenase 3α (IDH3α), a subunit of the IDH3 heterotetramer, decreased α-ketoglutarate levels and increased the stability and transactivation activity of HIF-1α in cancer cells. The silencing of IDH3α significantly delayed tumor growth by suppressing the HIF-1-mediated Warburg effect and angiogenesis. IDH3α expression was associated with the poor postoperative overall survival of lung and breast cancer patients. These results justify the exploitation of IDH3 as a novel target for the diagnosis and treatment of cancers.

Observation of low- and high-energy Gamow-Teller phonon excitations in nuclei.

Gamow-Teller (GT) transitions in atomic nuclei are sensitive to both nuclear shell structure and effective residual interactions. The nuclear GT excitations were studied for the mass number A = 42, 46, 50, and 54 "f-shell" nuclei in ((3)He, t) charge-exchange reactions. In the (42)Ca → (42)Sc reaction, most of the GT strength is concentrated in the lowest excited state at 0.6 MeV, suggesting the existence of a low-energy GT phonon excitation. As A increases, a high-energy GT phonon excitation develops in the 6-11 MeV region. In the (54)Fe → (54)Co reaction, the high-energy GT phonon excitation mainly carries the GT strength. The existence of these two GT phonon excitations are attributed to the 2 fermionic degrees of freedom in nuclei.

Effects of extracellular DNA from Candida albicans and pneumonia-related pathogens on Candida biofilm formation and hyphal transformation.

AIMS: The aim of this study was to investigate the effects of genomic DNA purified from Candida albicans and pneumonia-related pathogens, Pseudomonas aeruginosa and Staphylococcus aureus, on in vitro biofilm formation and morphological change of 3 Candida species (C. albicans, C. glabrata, and C. tropicalis). METHODS AND RESULTS: Biofilm formation was evaluated by the crystal violet assay and colony-forming unit counts. Morphological characteristics of biofilms were evaluated by scanning electron microscopy and fluorescence microscopy. Addition of DNA at a low concentration (<1·0 µg ml(-1)) significantly increased biofilm mass of all three Candida species. In contrast, the addition of DNA at a high concentration (10 µg ml(-1)) decreased the biofilm mass. Interestingly, the formation of hyphae in a dense network of yeast cells was observed in C. albicans biofilms exposed to a low concentration of DNA (<1·0 µg ml(-1)). CONCLUSIONS: These findings demonstrated that extracellular DNA (eDNA) plays a crucial role in Candida biofilm formation and suggested that eDNA may induce the morphological transition from yeast to hyphal growth form during C. albicans biofilm development. SIGNIFICANCE AND IMPACT OF THE STUDY: A novel therapy targeting eDNA may be applicable for Candida infection to decrease biofilm formation and hyphal formation.

Effects of extracellular DNA and DNA-binding protein on the development of a Streptococcus intermedius biofilm.

AIMS: The aim of this study was to clarify the effects of homologous and heterologous extracellular DNAs (eDNAs) and histone-like DNA-binding protein (HLP) on Streptococcus intermedius biofilm development and rigidity. METHODS AND RESULTS: Formed biofilm mass was measured with 0·1% crystal violet staining method and observed with a scanning electron microscope. The localizations of eDNA and extracellular HLP (eHLP) in formed biofilm were detected by staining with 7-hydoxyl-9H-(1,3-dichloro-9,9-dimethylacridin-2-one) and anti-HLP antibody without fixation, respectively. DNase I treatment (200 U ml(-1)) markedly decreased biofilm formation and cell density in biofilms. Colocalization of eHLP and eDNA in biofilm was confirmed. The addition of eDNA (up to 1 µg ml(-1)) purified from Strep. intermedius, other Gram-positive bacteria, Gram-negative bacteria, or human KB cells into the Strep. intermedius culture increased the biofilm mass of all tested strains of Strep. intermedius, wild-type, HLP-downregulated strain and control strains. In contrast, the addition of eDNA (>1 µg ml(-1)) decreased the biofilm mass of all Strep. intermedius strains. CONCLUSIONS: These findings demonstrated that eDNA and eHLP play crucial roles in biofilm development and its rigidity. SIGNIFICANCE AND IMPACT OF THE STUDY: eDNA- and HLP-targeting strategies may be applicable to novel treatments for bacterial biofilm-related infectious diseases.

Involvement of decreased hypoxia-inducible factor 1 activity and resultant G1-S cell cycle transition in radioresistance of perinecrotic tumor cells.

Cancer patients often suffer from local tumor recurrence after radiation therapy. Some intracellular and extracellular factors, such as activity of hypoxia-inducible factor 1 (HIF-1), cell cycle status and oxygen availability, have been suggested to affect DNA damage responses and eventual radioresistant characteristics of cancer cells. But when, where, and how these factors affect one another and induce cellular radioresistance is largely unknown. Here, we analyzed mechanistic and spatio-temporal relationships among them in highly heterogeneous tumor microenvironments. Experiments in vitro demonstrated that a decrease in the glucose concentration reduced the transcriptional activity of HIF-1 and expression of a downstream gene for the cell cycle regulator p27(Kip1) even under hypoxic conditions. Then, the proportion of cells in the radioresistant S phase increased, whereas that in the radiosensitive G1 phase decreased, significantly. Immunohistochemical analyses showed that cancer cells in perinecrotic hypoxic regions, which should be under low-glucose conditions, expressed little HIF-1α, and therefore, were mainly in S phase and less damaged by radiation treatment. Continuous administration of glucagon, which increases the blood glucose concentration and so improves glucose availability in perinecrotic hypoxic regions, induced HIF-1α expression and increased radiation-induced DNA damage. Taken all together, these results indicate that cancer cells in perinecrotic regions, which would be under low-glucose and hypoxic conditions, obtain radioresistance by decreasing the level of both HIF-1 activity and p27(Kip1) expression, and adjusting their cell cycle to the radioresistant S phase.

Heritability estimates for racing performance in Japanese Thoroughbred racehorses using linear and non-linear model analyses.

This study evaluated the differences between linear and non-linear modelled heritability estimates of racing performance based on lifetime earnings (LE) and lifetime ranking (LR) in Japanese Thoroughbred racehorses. The heritability estimate (h(2) = 0.25) obtained from a non-linear model based on formal Japan Racing Association ranking was much higher than that obtained from a linear model based on the original trait phenotype (h(2) = 0.11). The linear models showed slightly higher heritability estimates under the trait categorizations than under the original phenotypes, while the non-linear categorical trait models showed much higher heritability estimates than the linear models, especially for binary trait categorizations (h(2) = 0.34) with non-winning and winning horses. The binary trait categorizations were consistent with the case and control classifications in the previous genome-wide association study (GWAS), which identified possible sequence variants on ECA18 that affect racing performance in Japanese Thoroughbred racehorses. Those findings suggested that the different heritability estimates obtained from several trait categorizations would reflect the possible presence of susceptibility gene segregations in the analyzed population, indicating that heritability estimates from non-linear models are useful for the selection of case and control populations in GWAS.

A cohort study of racing performance in Japanese Thoroughbred racehorses using genome information on ECA18.

Using 1710 Thoroughbred racehorses in Japan, a cohort study was performed to evaluate the influence of genotypes at four single nucleotide polymorphisms (SNPs) on equine chromosome 18 (ECA18), which were associated in a previous genome-wide association study for racing performance with lifetime earnings and performance rank. In males, both g.65809482T>C and g.65868604G>T were related to performance rank (P= 0.005). In females, g.65809482T>C (P = 1.76E-6), g.65868604G>T (P=6.81E-6) and g.66493737C>T (P=4.42E-5) were strongly related to performance rank and also to lifetime earnings (P < 0.05). When win-race distance (WRD) among all winning racehorses and best race distance (BRD) among elite racehorses were considered as the phenotypes, significant associations (P<0.001) were observed for all four SNPs. The favourable race distance of both elite (BRD) and novice racehorses (WRD) was also associated with genotypes in the ECA18 region, indicating the presence of a gene in this region influencing optimum race distance in Thoroughbred racehorses. Therefore, the association with performance rank is likely due to the bias in the race distances. The location of the SNPs within and proximal to the gene encoding myostatin (MSTN) strongly suggests that regulation of the MSTN gene affects racing performance. In particular, the g.65809482T>C, g.65868604G>T and g.66493737C>T SNPs, or their combinations, may be genetic diagnostic markers for racing performance indicators such as WRD and BRD.

New method for quantitative assessment of airway calibre using a stereovision fibreoptic bronchoscope.

BACKGROUND: We have developed a new bronchoscopy system with two independent lenses at the tip of the device. This enables measurement of object size using the principle of triangulation. This study was performed to assess the accuracy of this system. METHODS: The accuracy of the bronchoscopy system was confirmed by measuring the diameters of four plastic tubes and 36 airway calibres in 12 surgical patients under general anaesthesia. The measured diameters of the tubes and airway tracts were compared with the manufactured diameters of tubes and those measured by high-resolution computed tomography (HRCT)-based virtual bronchoscopy, respectively. RESULTS: Using the new bronchoscope system, tube diameters, 9, 12, 15, and 19 mm, were measured as 9.9 (0.7), 12.8 (1.4), 16.3 (1.6), and 20.1 (2.0) mm, respectively. Airway calibres obtained by a stereovision bronchoscopy and HRCT-based virtual bronchoscopy were 8.66 (4.31) and 9.38 (5.09) mm, respectively. There is a significant correlation between airway calibres with the two measurement methods (r=0.975, P<0.01). CONCLUSIONS: We have confirmed that this new bronchoscopy system could provide relatively accurate quantitative data. This new system may be useful in the clinic to measure airway dimension and lesion sizes such as tumours.

Role of coerulean noradrenergic neurones in general anaesthesia in rats.

BACKGROUND: Central noradrenergic neurones have a role in alertness, analgesia, and thermoregulation; these neurones are also involved in the mechanism of anaesthesia. Locus coeruleus neurones innervate various central nervous regions including the cerebral cortex and hippocampus, and are responsible for wakefulness and analgesia. We hypothesized that these neurones are also involved in both activation of the γ-aminobutyric acid type A (GABA(A)) receptor and inhibition of N-methyl-d-aspartate (NMDA) receptor-mediated anaesthesia. METHODS: Forty-seven male rats were used to compare duration of anaesthesia before and 10 days after noradrenergic neurone depletion after intraperitoneal (i.p.) administration of N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4; 0, 5, and 50 mg kg(-1)). The animals received i.p. thiopental (GABA anaesthetic, 45 mg kg(-1)) or ketamine (NMDA anaesthetic, 100 mg kg(-1)). We also tested the effects of coerulean noradrenergic neurone depletion on i.p. ketamine analgesia (15 mg kg(-1)) using the hot-plate test in a further 21 male rats. At the end of each experiment, norepinephrine contents in the cerebral cortex and hippocampus were measured. RESULTS: I.P. DSP-4 5 and 50 mg kg(-1) significantly decreased ketamine anaesthesia duration by 12.7% and 22.4%, increased thiopental anaesthesia duration by 10.8% and 24.5%, and reduced ketamine-increased hot-plate latency by 55.2% and 68.1%, respectively. In addition, i.p. DSP-4 5 and 50 mg kg(-1) significantly reduced norepinephrine contents in coerulean brain regions by ∼20% and ∼75%, respectively. There were significant correlations between norepinephrine contents in coerulean brain regions and anaesthesia durations and ketamine analgesia. CONCLUSIONS: The present data indicate that coerulean noradrenergic neurones may be responsible for both GABA- and NMDA-mediated anaesthetic actions.