麻酔下ネコの下唇と口蓋における反射性副交感神経作動性血管拡張に対する視床下部前部阻害(Anterior hypothalamic inhibition of reflex parasympathetic vasodilatation in the lower lip and palate of anaesthetized cats)

麻酔下迷走・交感神経切除ネコにおいて、舌神経(LN)の中央切断部の電気刺激による下唇と口蓋の副交感神経介在性反射性血管拡張に対する視床下部の修飾作用について報告した。視床下部前部を電気刺激すると、LN刺激による唇血流増加が減弱した。その最も大きな阻害効果は視床下部前部の脳質周囲から誘発されていた。GABAA受容体特異的アンタゴニストのピクロトキシンを前投与すると、視床下部前部刺激の阻害効果が減弱したことから、視床下部の阻害効果はGABA様効果によって発現することが示唆された。興奮性アミノ酸のL-ホモシステイン酸を視床下部前部に微量注入すると、LN刺激による唇血流増加が有意に阻害されたことから、視床下部前部の細胞体が阻害作用に応答していることが示唆された。これはネコの口・顔面の非迷走神経性副交感神経反射に対する視床下部前部による修飾に関する初めての報告である。麻酔下迷走・交感神経切除ネコにおいて、舌神経(LN)の中央切断部の電気刺激による下唇と口蓋の副交感神経介在性反射性血管拡張に対する視床下部の修飾作用について報告した。視床下部前部を電気刺激すると、LN刺激による唇血流増加が減弱した。その最も大きな阻害効果は視床下部前部の脳質周囲から誘発されていた。GABAA受容体特異的アンタゴニストのピクロトキシンを前投与すると、視床下部前部刺激の阻害効果が減弱したことから、視床下部の阻害効果はGABA様効果によって発現することが示唆された。興奮性アミノ酸のL-ホモシステイン酸を視床下部前部に微量注入すると、LN刺激による唇血流増加が有意に阻害されたことから、視床下部前部の細胞体が阻害作用に応答していることが示唆された。これはネコの口・顔面の非迷走神経性副交感神経反射に対する視床下部前部による修飾に関する初めての報告である

The dopamine D1 receptor is expressed and facilitates relaxation in airway smooth muscle

Background: Dopamine signaling is mediated by Gs protein-coupled “D1-like” receptors (D1 and D5) and Gi-coupled “D2-like” receptors (D2-4). In asthmatic patients, inhaled dopamine induces bronchodilation. Although the Gi-coupled dopamine D2 receptor is expressed and sensitizes adenylyl cyclase activity in airway smooth muscle (ASM) cells, the Gs-coupled dopamine D1-like receptor subtypes have never been identified on these cells. Activation of Gs-coupled receptors stimulates cyclic AMP (cAMP) production through the stimulation of adenylyl cyclase, which promotes ASM relaxation. We questioned whether the dopamine D1-like receptor is expressed on ASM, and modulates its function through Gs-coupling. Methods: The mRNA and protein expression of dopamine D1-like receptor subtypes in both native human and guinea pig ASM tissue and cultured human ASM (HASM) cells was measured. To characterize the stimulation of cAMP through the dopamine D1 receptor, HASM cells were treated with dopamine or the dopamine D1-like receptor agonists (A68930 or SKF38393) before cAMP measurements. To evaluate whether the activation of dopamine D1 receptor induces ASM relaxation, guinea pig tracheal rings suspended under isometric tension in organ baths were treated with cumulatively increasing concentrations of dopamine or A68930, following an acetylcholine-induced contraction with or without the cAMP-dependent protein kinase (PKA) inhibitor Rp-cAMPS, the large-conductance calcium-activated potassium (BKCa) channel blocker iberiotoxin, or the exchange proteins directly activated by cAMP (Epac) antagonist NSC45576. Results: Messenger RNA encoding the dopamine D1 and D5 receptors were detected in native human ASM tissue and cultured HASM cells. Immunoblots confirmed the protein expression of the dopamine D1 receptor in both native human and guinea pig ASM tissue and cultured HASM cells. The dopamine D1 receptor was also immunohistochemically localized to both human and guinea pig ASM. The dopamine D1-like receptor agonists stimulated cAMP production in HASM cells, which was reversed by the selective dopamine D1-like receptor antagonists SCH23390 or SCH39166. A68930 relaxed acetylcholine-contracted guinea pig tracheal rings, which was attenuated by Rp-cAMPS but not by iberiotoxin or NSC45576. Conclusions: These results demonstrate that the dopamine D1 receptors are expressed on ASM and regulate smooth muscle force via cAMP activation of PKA, and offer a novel target for therapeutic relaxation of ASM

The dopamine D1 receptor is expressed and induces CREB phosphorylation and MUC5AC expression in human airway epithelium

Background Dopamine receptors comprise two subgroups, Gs protein-coupled “D1-like” receptors (D1, D5) and Gi-coupled “D2-like” receptors (D2, D3, D4). In airways, both dopamine D1 and D2 receptors are expressed on airway smooth muscle and regulate airway smooth muscle force. However, functional expression of the dopamine D1 receptor has never been identified on airway epithelium. Activation of Gs-coupled receptors stimulate adenylyl cyclase leading to cyclic AMP (cAMP) production, which is known to induce mucus overproduction through the cAMP response element binding protein (CREB) in airway epithelial cells. We questioned whether the dopamine D1 receptor is expressed on airway epithelium, and whether it promotes CREB phosphorylation and MUC5AC expression. Methods We evaluated the protein expression of the dopamine D1 receptor on native human airway epithelium and three sources of cultured human airway epithelial cells including primary cultured airway epithelial cells, the bronchial epithelial cell line (16HBE14o-), and the pulmonary mucoepidermoid carcinoma cell line (NCI-H292) using immunohistochemistry and immunoblotting. To characterize the stimulation of cAMP through the dopamine D1 receptor, 16HBE14o- cells and NCI-H292 cells were treated with dopamine or the dopamine D1 receptor agonists (SKF38393 or A68930) before cAMP measurements. The phosphorylation of CREB by A68930 in both 16HBE14o- and NCI-H292 cells was measured by immunoblot. The effect of dopamine or A68930 on the expression of MUC5AC mRNA and protein in NCI-H292 cells was evaluated by real-time PCR and immunofluorescence staining, respectively. Results The dopamine D1 receptor protein was detected in native human airway epithelium and three sources of cultured human airway epithelial cells. Dopamine or the dopamine D1-like receptor agonists stimulated cAMP production in 16HBE14o- cells and NCI-H292 cells, which was reversed by the selective dopamine D1-like receptor antagonists (SCH23390 or SCH39166). A68930 significantly increased phosphorylation of CREB in both 16HBE14o- and NCI-H292 cells, which was attenuated by the inhibitors of PKA (H89) and MEK (U0126). Expression of MUC5AC mRNA and protein were also increased by either dopamine or A68930 in NCI-H292 cells. Conclusions These results suggest that the activation of the dopamine D1 receptor on human airway epithelium could induce mucus overproduction, which could worsen airway obstructive symptoms

オンシュウミカン ノ ハナカラ ブンリシタ コウボ ノ ドウテイ ト セイシュ ジョウゾウ トクセイ

集積培養法によって温州ミカンの花から分離株 MK1～3 株を得た。その中で MK3 株は,生理学的試験と 16SrDNA-D1/D2 領域および ITS 領域の塩基配列に基づいた分子系統解析の結果から Saccharomyces cerevisiae と同定された。また Yeastcidin 耐性を有する事から,MK3 株が清酒酵母であることが示唆された。MK3 株は,清酒もろみにおけるアルコール生産量が 17.6%であり,清酒酵母協会 9 号株と同等の発酵力を示した。MK3 株を用いた製成酒は香気成分と有機酸に特徴的な組成を示した。特にMK3株を用いた製成酒は,低いコハク酸濃度,高いリンゴ酸/コハク酸比,高いカプロン酸エチル濃度,高いイソアミルアルコール/イソブチルアルコール比を示した。また,MK3 株は高泡を形成せず,TTC 還元性が Red であることから,清酒製造に実用可能な株であった。MK3 株は,特徴的な風味を形成できる実用酵母として清酒製造での利用が期待される。The MK3 strain was isolated from Satsuma Mandarin blossom by enriched culture method. On the basis of physiological tests and molecular analyses based on DNA sequences of 26S rDNA-D1/D2 region and ITS region, MK3 was identified as Saccharomyces cerevisiae. Furthermore, it was suggested that MK3 was sake yeast, since MK3 had a tolerance against Yeastcidin. The alcohol productivity of MK3 in sake mash was 17.6%. The MK3 possessed an equipollent fermentative ability in sake mash with sake yeast, kyokai No. 9. The sake produced by MK3 revealed distinguishing composition of aroma compounds and organic acids. In particular, the sake brewed by MK3 showed low succinic acid concentration, high malic acid/succinic acid ratio, high ethyl caproate concentration and high isoamyl alcohol/isobutyl alcohol ratio. The MK3 was a useful yeast for sake production, because it did not form taka-awa in sake mash and it was stained red with TTC. It is expected that the MK3 will be used for sake production as a useful yeast which is able to form characteristic flavor

Separated Transcriptomes of Male Gametophyte and Tapetum in Rice: Validity of a Laser Microdissection (LM) Microarray

In flowering plants, the male gametophyte, the pollen, develops in the anther. Complex patterns of gene expression in both the gametophytic and sporophytic tissues of the anther regulate this process. The gene expression profiles of the microspore/pollen and the sporophytic tapetum are of particular interest. In this study, a microarray technique combined with laser microdissection (44K LM-microarray) was developed and used to characterize separately the transcriptomes of the microspore/pollen and tapetum in rice. Expression profiles of 11 known tapetum specific-genes were consistent with previous reports. Based on their spatial and temporal expression patterns, 140 genes which had been previously defined as anther specific were further classified as male gametophyte specific (71 genes, 51%), tapetum-specific (seven genes, 5%) or expressed in both male gametophyte and tapetum (62 genes, 44%). These results indicate that the 44K LM-microarray is a reliable tool to analyze the gene expression profiles of two important cell types in the anther, the microspore/pollen and tapetum

Effect of the water disinfectant chlorine dioxide on the integrity of a reverse osmosis membrane

Chlorine dioxide has been used as a water disinfectant in water reclamation plants prior to the emergence of RO membrane process. However, the effects of chlorine dioxide on the integrity of RO membranes have yet to be fully understood. In this study, the influence of chlorine dioxide on RO membranes was investigated by observing chlorine dioxide reactions in the presence of iodide and bromide, structural changes of the RO membrane active layer polyamide and evolution in RO membrane assesses a solute passage (Rhodamine WT) and water flux. Batch experiments were performed to assess the reaction of chlorine dioxide, bromide and iodide in a potassium phosphate (10mM) buffered solution (pH=7.5). Iodide was found to react with chlorine dioxide over time while bromide did not under condition relevant to water treatment. On the other hand, chlorine dioxide oxidized bromide when the bromide concentration exceeded that of chlorine dioxide. Investigation of the influence of these compounds on the RO membrane polyamide using Rutherford back-scattering spectrometry (RBS) revealed that polyamide was underwent bromination but was more resistant to chlorination and iodination. These results suggest that chlorine dioxide oxidizes bromide although the reaction is slow, and it leads to polyamide bromination. Furthermore, RO membranes exposed to chlorine dioxide and bromide had significantly decreased the solutes rejection and water flux, while exposure to chlorine dioxide alone had no measureable influence. Therefore, we found that chlorine dioxide oxidation of bromide specifically leads to polyamide bromination and RO membrane deterioration

Functional Expression of GABAB Receptors in Airway Epithelium

γ-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the mammalian central nervous system and exerts its actions via both ionotropic (GABAA) and metabotropic (GABAB) receptors. The GABAB receptor is a dimer composed of R1 and R2 components and classically couples to the heterotrimeric Gi protein. In addition to their location on neurons, GABA and functional GABAB receptors have been detected in peripheral tissue such as airway smooth muscle. We questioned whether airway epithelium expresses receptors that could respond to GABA. We detected the mRNA encoding multiple-splice variants of the GABABR1 and GABABR2 in total RNA isolated from native human and guinea pig airway epithelium and human airway epithelial cell lines (BEAS-2B and H441). Immunoblots identified the GABABR1 and GABABR2 proteins in both guinea pig airway epithelium and BEAS-2B cells. The expression of GABABR1 protein was immunohistochemically localized to basal mucin-secreting and ciliated columnar epithelial cells in guinea pig trachea. Baclofen inhibited adenylyl cyclase activity, induced ERK phosphorylation and cross-regulated phospholipase C, leading to increased inositol phosphates in BEAS-2B cells in a pertussis toxin–sensitive manner, implicating Gi protein coupling. Thus, these receptors couple to Gi and cross-regulate the phospholipase C/inositol phosphate pathway. The second messengers of these pathways, cyclic AMP and calcium, play pivotal roles in airway epithelial cell primary functions of mucus clearance. Furthermore, the enzyme that synthesizes GABA, glutamic acid decarboxylase (GAD65/67), was also localized to airway epithelium. GABA may modulate an uncharacterized signaling cascade via GABAB receptors coupled to Gi protein in airway epithelium

Early Postoperative Nociceptive Threshold and Production of Brain-Derived Neurotrophic Factor Induced by Plantar Incision Are Not Influenced with Minocycline in a Rat: Role of Spinal Microglia

Background: Brain-derived neurotrophic factor (BDNF) from spinal microglia is crucial for aberrant nociceptive signaling in several pathological pain conditions, including postoperative pain. We assess the contribution of spinal microglial activation and associated BDNF overexpression to the early post-incisional nociceptive threshold. Methods: Male Sprague-Dawley rats were implanted with an intrathecal catheter. A postoperative pain model was established by plantar incision. Thermal and mechanical nociceptive responses were assessed by infrared radiant heat and von Frey filaments before and after plantar incision. Rats were injected intrathecally the microglial activation inhibitor minocycline before incision, 24 h after incision, or both. Other groups were subjected to the same treatments and the L4-L5 spinal cord segment removed for immunohistochemical analysis of microglia activation and BNDF expression. Results: Plantar incision reduced both thermal latency and mechanical threshold, indicating thermal hypersensitivity and mechanical allodynia. Minocycline temporally reduced thermal withdrawal latency but had no effect on mechanical withdrawal threshold, spinal microglial activity, or dorsal horn BDNF overexpression during the early post-incision period. Conclusion: These results suggest that spinal microglia does not contribute substantially to post-incisional nociceptive threshold. The BDNF overexpression response that may contribute to postoperative hyperalgesia and allodynia is likely derived from other sources