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Murakoshi T, Quintero RA, Bornick PW, Allen MH. In vivoendoscopic assessment of arterioarterial anastomoses: insight into their hemodynamic function. J Matern Fetal Neonatal Med 2009; 14:247-55. [PMID: 14738171 DOI: 10.1080/jmf.14.4.247.255] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To assess endoscopically the hemodynamic function of arterioarterial (AA) anastomoses in twin-twin transfusion syndrome (TTTS) and monochorionic selective intrauterine growth restriction (IUGR). MATERIALS AND METHODS The videotapes of TTTS and IUGR patients undergoing laser surgery between July 1997 and December 2001 were reviewed for the presence of AA anastomoses. The hemodynamic equator was defined as the site within the AA anastomosis with color flashing. AA anastomoses were classified as having unidirectional flow, having bi-directional flow, or being non-functional, depending on whether the hemodynamic equator reached a returning vein to one, both, or neither twin, respectively. TTTS was classified in stages as previously described. RESULTS AA anastomoses were present in 35/183 (19.1%) of TTTS and in 12/24 (50%) IUGR patients. Of these, the hemodynamic equator was visible in 8/35 (22.8%) TTTS patients (all in stage III, and mostly in atypical stage III) and in 6/12 (50%) IUGR patients (overall 14/47, 29.8%). Of the 14 patients with a visible hemodynamic equator, 13 (92.8%) AA anastomoses showed unidirectional (9/13, 69.2% from the smaller to the larger twin) flow, and only 1/14 (7.1%) showed bi-directional flow. CONCLUSION The hemodynamic equator is visible in approximately 30% of patients with AA anastomoses. Within this group, most AA anastomoses behave as functional arteriovenous anastomoses, and the direction of flow can be from the smaller to the larger twin or vice versa. The data suggest a correlation between sonographic findings and placental vascular design, also implying possible interfetal oxygenation differences. Further assessment of the functional behavior of AA anastomoses is warranted to understand the pathophysiology of TTTS and selective IUGR.
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Kanamaru T, Oshiro H, Matsuto T, Murakoshi T, Aihara K. Modeling study of synchronized inhibition in the amygdala. Neurosci Res 2009. [DOI: 10.1016/j.neures.2009.09.256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Ohshiro H, Murakoshi T. Receptor subtype analysis of dopaminergic modulation of inhibitory network oscillation in the rat amygdala. Neurosci Res 2009. [DOI: 10.1016/j.neures.2009.09.680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ito H, Nagano M, Suzuki H, Murakoshi T. Hyperlocomotion and elevated synaptic plasticity in the anterior cingulate cortex in mice after chronic restraint stress. Neurosci Res 2009. [DOI: 10.1016/j.neures.2009.09.1000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Murakoshi T, Ishii K, Nakata M, Sago H, Hayashi S, Takahashi Y, Murotsuki J, Matsushita M, Shinno T, Naruse H, Torii Y. Validation of Quintero stage III sub-classification for twin-twin transfusion syndrome based on visibility of donor bladder: characteristic differences in pathophysiology and prognosis. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2008; 32:813-818. [PMID: 18956440 DOI: 10.1002/uog.6226] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE To validate the Quintero stage III subclassification for twin-twin transfusion syndrome (TTTS) based on visibility of the bladder of the donor twin. METHODS Between July 2002 and August 2006, there were 131 pregnant Japanese women affected by severe TTTS before 26 weeks' gestation, treated with fetoscopic laser surgery at five centers in Japan, whose pregnancies continued beyond 22 weeks. Outcome data were available in all cases and surviving infants were followed up for at least 6 years. This study focused on the Stage III TTTS patients. These were subclassified into Stage III atypical (abnormal Doppler flow with visible donor bladder) and Stage III classical (abnormal Doppler flow with non-visible donor bladder) groups. Perioperative data and postnatal outcomes were compared between the groups. RESULTS Seven Stage I, 22 Stage II, 82 Stage III and 20 Stage IV pregnancies continued beyond 22 weeks. There was a significantly higher incidence of absent or reversed end-diastolic velocity in the umbilical artery (UA-AREDV) of the donor in Stage III atypical than in Stage III classical patients (83.8% vs. 53.3%, P = 0.004). Stage III atypical cases also had a significantly higher incidence of arterioarterial (AA) anastomoses (72.9% vs. 17.8%, P < 0.001) and intrauterine fetal demise (IUFD) of the donor (43.2% vs. 13.3%, P = 0.002). However, there were no differences in overall survival or in abnormal brain scans of surviving infants. Donors with both UA-AREDV and AA anastomoses had a significantly higher incidence of IUFD compared with the others (53.3%, P < 0.001). CONCLUSIONS Quintero stage III atypical was characterized by a high incidence of AA anastomoses and UA-AREDV of the donor, resulting in IUFD. Subclassification of Stage III based on visibility of the bladder of the donor twin was adequate for and compatible with differentiating prognosis and pathophysiology.
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Murakoshi T, Osada Y. The effects of active attention on the change detection task. J Vis 2008. [DOI: 10.1167/8.6.668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Koshiishi T, Osada H, Hata A, Furugen Y, Murakoshi T, Mitsuhashi N. Prenatal rupture of right ventricular diverticulum: a case report and review of the literature. Prenat Diagn 2007; 27:1154-7. [PMID: 17787028 DOI: 10.1002/pd.1833] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Osanai M, Saegusa H, Kazuno AA, Nagayama S, Hu Q, Zong S, Murakoshi T, Tanabe T. Altered cerebellar function in mice lacking CaV2.3 Ca2+ channel. Biochem Biophys Res Commun 2006; 344:920-5. [PMID: 16631598 DOI: 10.1016/j.bbrc.2006.03.206] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Accepted: 03/30/2006] [Indexed: 10/24/2022]
Abstract
Voltage-dependent Ca(2+) channels play important roles in cerebellar functions including motor coordination and learning. Since abundant expression of Ca(V)2.3 Ca(2+) channel gene in the cerebellum was detected, we searched for possible deficits in the cerebellar functions in the Ca(V)2.3 mutant mice. Behavioral analysis detected in delayed motor learning in rotarod tests in mice heterozygous and homozygous for the Ca(V)2.3 gene disruption (Ca(V)2.3+/- and Ca(V)2.3-/-, respectively). Electrophysiological analysis of mutant mice revealed perplexing results: deficit in long-term depression (LTD) at the parallel fiber Purkinje cell synapse in Ca(V)2.3+/- mice but apparently normal LTD in Ca(V)2.3-/- mice. On the other hand, the number of spikes evoked by current injection in Purkinje cells under the current-clamp mode decreased in Ca(V)2.3 mutant mice in a gene dosage-dependent manner, suggesting that Ca(V)2.3 channel contributed to spike generation in Purkinje cells. Thus, Ca(V)2.3 channel seems to play some roles in cerebellar functions.
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Saitow F, Murakoshi T, Suzuki H, Konishi S. Metabotropic P2Y purinoceptor-mediated presynaptic and postsynaptic enhancement of cerebellar GABAergic transmission. J Neurosci 2005; 25:2108-16. [PMID: 15728851 PMCID: PMC6726053 DOI: 10.1523/jneurosci.4254-04.2005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2004] [Revised: 01/18/2005] [Accepted: 01/18/2005] [Indexed: 11/21/2022] Open
Abstract
Cerebellar GABAergic inhibitory transmission is under heterosynaptic control mediated by diverse chemical messengers. Here, we investigated roles of metabotropic P2Y purinoceptors (P2YRs) on GABAergic synapses between cerebellar interneurons and Purkinje cells (PCs). Activation of P2Y purinoceptors by two selective agonists, ADP and 2-methylthio-ADP (2MeSADP), elicited two distinct forms of synaptic plasticity of GABAergic transmission in the cerebellar cortex. First, the two agonists induced long-lasting enhancement of stimulation-evoked GABAergic IPSCs as well as GABA(A) receptor currents in PCs. This effect was completely abolished by intracellular infusion of the Ca2+-chelating agent BAPTA. Measurements of intracellular Ca2+ ([Ca2+]i) dynamics showed that puff application of 2MeSADP produced an increase in [Ca2+]i of PCs and that this increase persisted in an external Ca2+-deficient medium. These results suggest that P2Y activation postsynaptically elicits long-term enhancement of GABA(A) receptor sensitivity of PCs through a Gq-mediated increase in [Ca2+]i. The other action of P2YR agonists on cerebellar GABAergic synapses was that they produced a short-term increase in the frequency and the amplitude of spontaneous GABAA receptor-mediated IPSCs in PCs in a manner sensitive to a P2Y1R antagonist, N6-methyl 2'-deoxyadenosine 3',5'-bisphosphate. This action appeared to be attributable to an excitability increase in presynaptic GABAergic interneurons, because ADP excited all Lugaro cells examined and some of interneurons in the molecular layer. These results suggest that activation of cerebellar P2Y purinoceptors leads to modulation of GABAergic transmission in different spatial and temporal domains, namely short-term and long-term plasticity through presynaptic and postsynaptic mechanisms at interneuron-->PC inhibitory synapses in the rat cerebellar cortex.
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Murakoshi T, Nagano M, Suzuki H. Research on fear/anxiety. J NIPPON MED SCH 2004; 71:82-3. [PMID: 15260079 DOI: 10.1272/jnms.71.82] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Takei T, Saegusa H, Zong S, Murakoshi T, Makita K, Tanabe T. Increased sensitivity to halothane but decreased sensitivity to propofol in mice lacking the N-type Ca2+ channel. Neurosci Lett 2003; 350:41-5. [PMID: 12962913 DOI: 10.1016/s0304-3940(03)00634-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Volatile anesthetics are known to depress excitatory synaptic transmission. Inhibition of voltage-dependent Ca2+ channels is speculated to underlie this mechanism, which remains to be clarified in vivo. We examined the sensitivity to halothane in mice lacking the N-type Ca2+ channel, a major contributor of presynaptic neurotransmitter release. Sensitivity to halothane was significantly increased in the knockout mice compared with the wild-type littermates. Halothane also depressed field excitatory postsynaptic potentials recorded from the Schaffer collateral-CA1 hippocampal synapses more greatly in the knockout mice. We further examined sleep time induced by injection of propofol, an intravenous anesthetic that mainly affects inhibitory synaptic transmission. In contrast, sensitivity to propofol was significantly decreased in the knockout mice. We suggest that inhibition of the N-type Ca2+ channel underlies mechanisms of halothane anesthesia but counteracts propofol anesthesia.
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Takei T, Saegusa H, Zong S, Murakoshi T, Makita K, Tanabe T. Anesthetic sensitivities to propofol and halothane in mice lacking the R-type (Cav2.3) Ca2+ channel. Anesth Analg 2003; 97:96-103, table of contents. [PMID: 12818950 DOI: 10.1213/01.ane.0000065548.83253.5c] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
UNLABELLED Because inhibition of voltage-dependent Ca(2+) channels can be a mechanism underlying general anesthesia, we examined sensitivities to propofol and halothane in mice lacking the R-type (Ca(v)2.3) channel widely expressed in neurons. Sleep time after propofol injection (26 mg/kg IV) and halothane MAC(RR) and MAC (50% effective concentrations for the loss of the righting reflex and for the tail pinch/withdrawal response, respectively) were determined. Significantly shorter propofol-induced sleep time (291.6 +/- 16.8 s versus 344.4 +/- 12.1 s) and larger halothane MAC(RR) (1.11% +/- 0.04% versus 0.98% +/- 0.03%) were observed in Ca(v)2.3 channel knockouts (Ca(v)2.3(-/-)) than in wild-type (Ca(v)2.3(+/+)) litter mates. To investigate the basis of the decreased anesthetic sensitivities in vivo, field excitatory postsynaptic potentials and population spikes (PSs) were recorded from Schaffer collateral CA1 synapses in hippocampal slices. Propofol (10-30 micro M) inhibited PSs by potentiating gamma-aminobutyric acid-ergic inhibition, and this potentiation was markedly smaller at 30 micro M in Ca(v)2.3(-/-) mice, possibly accounting for the decreased propofol sensitivity in vivo. Halothane (1.4%-2.2%) inhibited field excitatory postsynaptic potentials similarly in both genotypes, whereas 1%-2% halothane depressed PSs more in Ca(v)2.3(-/-) mice, suggesting the postsynaptic role of the R-type channel in the propagation of excitation and other mechanisms underlying the increased halothane MAC(RR) in Ca(v)2.3(-/-) mice. IMPLICATIONS Because inhibition of neuronal Ca(2+) currents can be a mechanism underlying general anesthesia, we examined anesthetic sensitivities in mice lacking the R-type (Ca(v)2.3) Ca(2+) channels both in vivo and in hippocampal slices. Decreased sensitivities in mutant mice imply a possibility that agents blocking this channel may increase the requirements of anesthetics/hypnotics.
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Sakata Y, Saegusa H, Zong S, Osanai M, Murakoshi T, Shimizu Y, Noda T, Aso T, Tanabe T. Ca(v)2.3 (alpha1E) Ca2+ channel participates in the control of sperm function. FEBS Lett 2002; 516:229-33. [PMID: 11959138 DOI: 10.1016/s0014-5793(02)02529-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To know the function of the Ca2+ channel containing alpha(1)2.3 (alpha1E) subunit (Ca(v)2.3 channel) in spermatozoa, we analyzed Ca2+ transients and sperm motility using a mouse strain lacking Ca(v)2.3 channel. The averaged rising rates of Ca2+ transients induced by alpha-D-mannose-bovine serum albumin in the head region of Ca(v)2.3-/- sperm were significantly lower than those of Ca(v)2.3+/+ sperm. A computer-assisted sperm motility assay revealed that straight-line velocity and linearity were greater in Ca(v)2.3-/- sperm than those in Ca(v)2.3+/+ sperm. These results suggest that the Ca(v)2.3 channel plays some roles in Ca2+ transients and the control of flagellar movement.
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Tsunemi T, Saegusa H, Ishikawa K, Nagayama S, Murakoshi T, Mizusawa H, Tanabe T. Novel Cav2.1 splice variants isolated from Purkinje cells do not generate P-type Ca2+ current. J Biol Chem 2002; 277:7214-21. [PMID: 11756409 DOI: 10.1074/jbc.m108222200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The alpha(1)2.1 (alpha(1A)) subunits of P-type and Q-type Ca(2+) channels are encoded by a single gene, Cacna1a. Although these channels differ in the inactivation kinetics and sensitivity to omega-agatoxin IVA, the mechanism underlying these differences remains to be clarified. Alternative splicings of the Cacna1a transcript have been postulated to contribute to the respective properties, however, the splice variants responsible for P-type Ca(2+) channels have not been identified. To explore P-type-specific splice variants, we aimed at cloning alpha(1)2.1 from isolated mouse Purkinje cells using single-cell reverse transcription-PCR, because in Purkinje cells P-type currents dominate over the whole currents (>95%) with Q-type currents undetected. As a result, two novel splice variants were cloned. Compared with the previously cloned mouse alpha(1)2.1, two novel variants had additional 48 amino acids at the amino termini, six single amino acid changes, and splicing variations at the exon 46/47 boundary, which produced different carboxyl termini. Furthermore, one variant had one RNA editing site. However, electrophysiological and pharmacological studies indicated that these variants did not generate P-type current in cultured cells. These results suggest that P-type-specific splice variants may exist but that post-translational processing or modification by uncharacterized interacting proteins is also required for generating the P-type current.
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Toriyama H, Wang L, Saegusa H, Zong S, Osanai M, Murakoshi T, Noda T, Ohno K, Tanabe T. Role of Ca(v) 2.3 (alpha1E ) Ca2+ channel in ischemic neuronal injury. Neuroreport 2002; 13:261-5. [PMID: 11893922 DOI: 10.1097/00001756-200202110-00018] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We investigated the role of the Ca(v)2.3 (alpha1E) channel in ischemic neuronal injury using Ca(v)2.3 mutant mice. In focal ischemia model with a complete occlusion of the middle cerebral artery in vivo, infarct at 24 h was significantly larger in Ca(v)2.3 mutant mice compared with that in wild-type controls. In vitro Ca2+ imaging studies using hippocampal slices revealed that oxygen-glucose deprivation induced a [Ca2+]i increase in the hippocampal CA1 region more vigorously in Ca(v)2.3 mutant mice than in wild-type controls, and that tetrodotoxin or bicuculline application abolished the difference between the genotypes. These results suggest that the Ca(v)2.3 channel plays a protective role in ischemic neuronal injury by a mechanism in which GABAergic neuronal actions are involved.
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Sakata Y, Saegusa H, Zong S, Osanai M, Murakoshi T, Shimizu Y, Noda T, Aso T, Tanabe T. Analysis of Ca(2+) currents in spermatocytes from mice lacking Ca(v)2.3 (alpha(1E)) Ca(2+) channel. Biochem Biophys Res Commun 2001; 288:1032-6. [PMID: 11689014 DOI: 10.1006/bbrc.2001.5871] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In mammalian male germ-line cells, low-voltage-activated (LVA) Ca(2+) current has been identified and its electrophysiological properties have been studied. To investigate whether alpha(1)2.3 (alpha(1E)) subunit of the voltage-dependent Ca(2+) channel codes for the LVA current, whole-cell patch clamp and following reverse transcription-polymerase chain reaction (RT-PCR) experiments were performed in pachytene spermatocytes from Ca(v)2.3+/+ and Ca(v)2.3-/- mice. Whole-cell current in acutely dissociated pachytene spermatocytes from Ca(v)2.3+/+ and Ca(v)2.3-/- mice displayed a typical profile of LVA Ca(2+) currents and kinetics with no significant differences. Single-cell RT-PCR revealed the expression of Cacna1g in the pachytene spermatocytes from Ca(v)2.3+/+ and Ca(v)2.3-/- mice in which LVA Ca(2+) currents were actually recorded. These results suggest that the Ca(v)2.3 channel makes no detectable contribution to the LVA Ca(2+) current in the pachytene spermatocyte. Instead, Ca(v)3 family such as Ca(v)3.1 may be the likely candidates responsible for the LVA currents in pachytene spermatocytes.
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Murakoshi T, Song SY, Konishi S, Tanabe T. Multiple G-protein-coupled receptors mediate presynaptic inhibition at single excitatory synapses in the rat visual cortex. Neurosci Lett 2001; 309:117-20. [PMID: 11502359 DOI: 10.1016/s0304-3940(01)02051-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Modulation of excitatory synaptic transmission by agonists for several neurotransmitter receptors was investigated at intrinsic cortical synapses derived from single presynaptic neurons. Excitatory postsynaptic currents (EPSCs) were recorded from layer 5 pyramidal neurons in the rat visual cortex in response to minimal stimulation within the same layer. 5-hydroxytryptamine, adenosine, baclofen, carbachol and DCG-IV all suppressed EPSCs with an increase in paired-pulse ratio. These agonists reduced the frequency of miniature EPSCs without significantly affecting their amplitude distribution. These results suggest that glutamatergic excitatory transmission in the neocortex is under the control of presynaptic inhibition mediated by multiple neuromodulator receptors co-expressed in single presynaptic terminals.
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Kubota M, Murakoshi T, Saegusa H, Kazuno A, Zong S, Hu Q, Noda T, Tanabe T. Intact LTP and fear memory but impaired spatial memory in mice lacking Ca(v)2.3 (alpha(IE)) channel. Biochem Biophys Res Commun 2001; 282:242-8. [PMID: 11263998 DOI: 10.1006/bbrc.2001.4572] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To investigate the functional roles of the Ca(v)2.3 (alpha(1E)) channel in hippocampal CA1 pyramidal neurons, we studied in vitro synaptic properties and in vivo behaviors of the Ca(v)2.3 gene deficient mice. The Ca(v)2.3 channel mRNA was identified in the hippocampal formation of the wild-type mouse by in situ hybridization. The basic excitatory synaptic transmission and long-term potentiation by theta-burst stimulation were intact in CA1 region of Ca(v)2.3-/- mice. We performed two forms of behavioral tests to examine the hippocampus-dependent function, i.e., emotional and spatial learning tests. The Ca(v)2.3-/- mice were able to establish and maintain fear memories. Although general improvement in the performance of Morris water maze test was seen in Ca(v)2.3-/- mice, they displayed an obvious impairment in the probe test. These results suggest that the Ca(v)2.3 channel plays some role in formation of the accurate spatial memory but not of the fear memory.
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Murakoshi T, Yamamori K, Tojo Y, Naruse H, Seguchi M, Torii Y, Maeda K. Pulmonary stenosis in recipient twins in twin-to-twin transfusion syndrome: report on 3 cases and review of literature. Croat Med J 2000; 41:252-6. [PMID: 10962042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
This report describes 3 cases of pulmonary stenosis in the recipient twin in twin-twin transfusion syndrome. Fetal echocardiography showed cardiomegaly, tricuspid valve regurgitation, and increased reverse flow in the inferior vena cava, as signs of congestive heart failure in all 3 cases. We diagnosed 2 cases of pulmonary stenosis by fetal echocardiography prenatally and confirmed our findings in all 3 cases postnatally. Two cases underwent postnatal balloon valvuloplasty to release the pulmonary valvular stenosis in neonatal period. The third one died soon after delivery and autopsy showed a slightly thickened pulmonary valve. One of the cases was diagnosed in the early second trimester (20 weeks of pregnancy), the earliest detection of fetal pulmonary stenosis reported in literature. The presence of high peak velocity of the pulmonary artery at 20 weeks of pregnancy preceded the development of pulmonary stenosis in this case. This supports the hypothesis that alterations in fetal hemodynamics may result in structural cardiac abnormality.
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Yamamoto N, Utsu M, Serizawa M, Ohki S, Murakoshi T, Seguchi M, Iwase K, Maeda K. Neonatal periventricular leukomalacia preceded by fetal periventricular echodensity. Fetal Diagn Ther 2000; 15:198-208. [PMID: 10867479 DOI: 10.1159/000021006] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE The purpose of this prospective study is to verify whether fetal periventricular echodensity (PVE) precedes neonatal periventricular leukomalacia (PVL). METHODS Fetal brains were studied with transvaginal scan in 63 high-risk fetuses from 17 to 32 weeks of pregnancy, PVE echogenicity was quantified with ultrasonic histogram, and neonatal brains and clinical courses were studied after birth. RESULTS No fetal cystic PVL was found, instead, fetal PVE was detected in 42 fetuses. The quantified echogenicity value was higher in PVE than in normal brain. Four cases developed neonatal PVL among 28 preterm and 1 among 14 term births. Neonatal PVL developed in the 23 cases of persistent fetal PVE, whereas no neonatal PVL was found when fetal PVE was negative or disappeared. Cord compression signs were common in PVL cases. CONCLUSION Neonatal PVL was preceded by antepartum persistent fetal PVE in the present study.
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Toru S, Murakoshi T, Ishikawa K, Saegusa H, Fujigasaki H, Uchihara T, Nagayama S, Osanai M, Mizusawa H, Tanabe T. Spinocerebellar ataxia type 6 mutation alters P-type calcium channel function. J Biol Chem 2000; 275:10893-8. [PMID: 10753886 DOI: 10.1074/jbc.275.15.10893] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Abnormal CAG repeat expansion in the alpha1A voltage-dependent calcium channel gene is associated with spinocerebellar ataxia type 6, an autosomal dominant cerebellar ataxia with a predominant loss of the Purkinje cell. A reverse transcriptase-polymerase chain reaction analysis of mRNA from mouse Purkinje cells revealed a predominant expression of the alpha1A channel lacking an asparagine-proline (NP) stretch in the domain IV (alpha1A(-NP)). Human alpha1A channels carrying various polyglutamine length with or without NP were expressed in HEK293 cells, and channel properties were compared using a whole-cell voltage clamp technique. alpha1A(-NP), corresponding to P-type channel, with 24 and 28 polyglutamines found in patients showed the voltage dependence of inactivation shifting negatively by 6 and 11 mV, respectively, from the 13 polyglutamine control. Contrarily, the alpha1A channel with NP (alpha1A(+NP)), corresponding to Q-type channel, with 28 polyglutamines exhibited a positive shift of 5 mV. These results suggest that altered function of alpha1A(-NP) may contribute to degeneration of Purkinje cells, which express predominantly alpha1A(-NP), due to the reduced Ca(2+) influx resulting from the negative shift of voltage-dependent inactivation. On the other hand, other types of neurons, expressing both alpha1A(-NP) and alpha1A(+NP), may survive because the positive shift of voltage-dependent inactivation of alpha1A(+NP) compensates Ca(2+) influx.
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Endoh M, Suzuki Y, Nakayama S, Murakoshi T, Saitoh I. [A case of successful palliative operation of asplenia syndrome with total anomalous pulmonary venous return in young infant]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 1999; 52:860-3. [PMID: 10478551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
We reported a successful palliative operation for asplenia syndrome with total anomalous pulmonary venous return (TAPVR Ia) in an infant. The boy was suffering from cyanosis and tachypnea. He was diagnosed as asplenia syndrome with TAPVR and hiatus hernia. After he was admitted to our hospital, pulmonary congestion gradually progressed in a month. At 58 days of age, a palliative operation (repair of TAPVR and pulmonary artery banding with band of 20 mm in length) was performed. The postoperative course was uneventful. At 114 days of age, he underwent curative operation for hiatus hernia without cardiac failure. Postoperative cardiac catheterization at 179 days of age showed appropriate pulmonary artery pressure. We emphasize that pulmonary artery banding which is tighter than usual well controls pulmonary blood flow, although the length of the band in each case should be considered individually.
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Tsukamoto T, Shibagaki Y, Murakoshi T, Suzuki M, Nakamura A, Gotoh H, Mizumoto K. Cloning and characterization of two human cDNAs encoding the mRNA capping enzyme. Biochem Biophys Res Commun 1998; 243:101-8. [PMID: 9473487 DOI: 10.1006/bbrc.1997.8038] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Previous studies demonstrated that the mammalian mRNA capping enzyme is a bifunctional enzyme containing RNA 5'-triphosphatase and mRNA guanylyl-transferase activities in a single polypeptide. In yeast, both the above activities are separated into two different subunits, alpha and beta, the genes for which we have cloned recently. It is thus interesting to compare the structural and functional relationships between the mammalian and yeast capping enzymes. Here we isolated two human cDNAs encoding mRNA capping enzymes termed hCAP1a and hCAP1b which encode 597 and 541 amino acids, respectively. They are different only at the region coding for the C-terminal portion of the enzyme. Comparison of the deduced amino acid sequences with other cellular and viral capping enzymes showed that all the regions conserved among mRNA guanylyltransferases are observed in our clones except one conserved C-terminal region which was absent in the hCAP1b protein. The purified recombinant hCAP1a gene product, hCAP1a, exhibited both RNA 5'-triphosphatase and mRNA guanylyltransferase activities. Deletion mutant analysis of hCAP1a showed that the N-terminal 213 amino acid fragment containing a tyrosine specific protein phosphatase motif catalyzed the RNA 5'-triphosphatase activity and the C-terminal 369 amino acid fragment exhibited the mRNA guanylyltransferase activity. On the other hand, hCAP1b showed RNA 5'-triphosphatase activity, but neither enzyme-GMP covalent complex formation nor cap structure formation was detected.
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Tsukamoto T, Shibagaki Y, Imajoh-Ohmi S, Murakoshi T, Suzuki M, Nakamura A, Gotoh H, Mizumoto K. Isolation and characterization of the yeast mRNA capping enzyme beta subunit gene encoding RNA 5'-triphosphatase, which is essential for cell viability. Biochem Biophys Res Commun 1997; 239:116-22. [PMID: 9345280 DOI: 10.1006/bbrc.1997.7439] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The yeast Saccharomyces cerevisiae mRNA capping enzyme is composed of two subunits of alpha (52 kDa, mRNA guanylyltransferase) and beta (80 kDa, RNA 5'-triphosphatase). We have isolated the alpha subunit gene (CEG1) by immunological screening. In this report, with the aid of partial amino acid sequences of purified yeast capping enzyme, we isolated the gene, designated CET1, encoding the S. cerevisiae capping enzyme beta subunit. Amino acid sequence analysis revealed that the gene encodes for 549 amino acids with a calculated M(r) of 61,800 which is unexpectedly smaller than the size estimated by SDS-PAGE. Gene disruption experiment showed that CET1 is essential for yeast cell growth. The purified recombinant CET1 gene product, Cet1, exhibited an RNA 5'-triphosphatase activity which specifically removed the gamma-phosphate from the triphosphate-terminated RNA substrate, but not from nucleoside triphosphates, confirming the identity of the gene. Interaction between the Cet1 and the Ceg1 was also studied by the West-Western procedure using recombinant Ceg1-[32P]GMP as probe.
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Urayama O, Murakoshi T, Kubota M, Hara Y, Chihara J, Ikawa Y. Coincident induction of K rev-1/rap 1A, rap 1B and H-ras mRNAs in the rat spinal cord by noxious stimulation. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1997; 45:331-4. [PMID: 9149109 DOI: 10.1016/s0169-328x(97)00024-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Two cDNA fragments, K rev-1/rap 1A and rap 1B, were amplified from total cellular RNA of the rat spinal cord by reverse transcription-polymerase chain reaction with a set of oligonucleotide primers specific for the human rap 1A cDNA. We report here using Northern blot analysis with these cDNA probes that noxious stimulation causes a marked and coincident increase in rap 1A, rap 1B and H-ras mRNAs in the rat spinal cord. This suggests that Rap 1 participates in sensory processing in spinal neurons in parallel with Ras.
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