- 著者
- Ito Takaaki Ikeda Kazuo Tomita Katsuro Yokoyama Shigeru
- 出版者
- Elsevier
- 雑誌
- Neuroscience Letters (ISSN:03043940)
- 巻号頁・発行日
- vol.472, no.2, pp.104-108, 2010-03-19
- 被引用文献数
- 9
The interleukin-6 (IL-6) family of cytokines is thought to be involved in the development and regeneration of peripheral nerves; however, their roles in myelination remain unclear. In this study, we examined the effects of IL-6 on the expression of genes for compact myelin proteins using Schwann cell cultures prepared by multiple explantation of adult rat sciatic nerves. In semi-quantitative reverse transcription-polymerase chain reaction analysis, stimulation of Schwann cells with IL-6 significantly increased the mRNA level of peripheral myelin protein 22 (PMP22), but not those of myelin protein zero and myelin basic protein. The increase in PMP22 mRNA was markedly suppressed by AG490, a Janus kinase 2 (JAK2) inhibitor, but not significantly by PD098059, a mitogen-activated protein kinase inhibitor. Immunocytochemical staining revealed that IL-6 enhanced immunoreactivities for the phosphorylated forms of both JAK2 and signal transducer and activator of transcription 3 (STAT3), as well as that for PMP22. These results indicate that IL-6 can enhance PMP22 production in Schwann cells via a JAK2-dependent pathway by probably activating STAT3 and thus may contribute to myelination. © 2010 Elsevier Ireland Ltd. All rights reserved.
- 著者
- Tabuchi Masashi Inoue Shigeki Kanzaki Ryohei Nakatani Kei
- 出版者
- Elsevier Ireland Ltd.
- 雑誌
- Neuroscience letters (ISSN:03043940)
- 巻号頁・発行日
- vol.528, no.1, pp.61-66, 2012-10
- 被引用文献数
- 8 1
Kenyon cells (KCs), which are present in the mushroom bodies (MBs) of the insect brain, play an important role in olfactory information processing and associative learning. However, the intrinsic electrophysiological properties of KCs in silkmoth (Bombyx mori) MBs remain unknown. Here, we use whole-cell patch-clamp recordings to elucidate the functional parameters of membrane voltage and voltage-activated ionic currents of KCs in silkmoth MBs. KCs generated action potentials in response to stepping pulses of depolarizing current, and application of GABA-receptor blocker abolished inhibitory synaptic inputs and depolarized resting membrane potential. Pharmacological isolation of KC voltage-gated ionic currents revealed that KCs express a range of voltage-activated channels, including transient and non-inactivating potassium, sodium, and calcium channels. Our results provide the first electrophysiological characterization of KCs in silkmoth MBs and represent an important step toward understanding neuronal computation that underlies olfactory information processing in silkmoths.
- 著者
- Tsukiyama Tadasuke Yamaguchi Terry P.
- 出版者
- Elsevier Ireland
- 雑誌
- Neuroscience Letters (ISSN:03043940)
- 巻号頁・発行日
- vol.512, no.1, pp.48-52, 2012-03-14
- 被引用文献数
- 29
Wnts are secreted glycoproteins that play important roles in embryonic development. Wnt2b is transiently expressed in the primitive streak (PS) during gastrulation and in several organs during organogenesis. To determine the biological function of Wnt2b during mouse development, we established a conditional null allele of Wnt2b. Mice lacking Wnt2b were viable, fertile, and displayed a normal life span, however, the olfactory bulb in adult Wnt2b mutant mice was significantly reduced in length. Our results suggest that Wnt2b primarily plays a supportive role in gastrulation and organogenesis, functioning redundantly with canonical Wnts, such as Wnt2, in numerous tissues.