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Abstract. Drosophila larval muscles are commonly used for developmental assessment in regard to various mutations of synaptically relevant molecules. In addition, the molecular sequence of the glutamate receptors on the muscle fibre have been described; however, the pharmacological profiles to known agonists and antagonists have yet to be reported. Here, the responses of N -methyl- d -aspartic acid, α-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA), l -glutamate, kainate, quisqualic acid, NBQX, AP5 and DNQX are characterized with regard to synaptic transmission and direct effects on the muscle fibres. The muscle fibres depolarize to application of glutamate or quisqualate and the excitatory postsynaptic potential (EPSP) amplitudes are diminished. Kainate does not alter the muscle membrane potential but does reduce the EPSP amplitude. The known antagonists NBQX, AP5 and DNQX have no substantial effect on synaptic transmission at 1 m m , nor do they block the response of quisqualate. Kainate may be acting as a postsynaptic antagonist or via autoreceptors presynaptically to reduce evoked transmission. 相似文献
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The homologous sequences of human or mouse SOX1, SOX4 and SOX11 , and one novel Sox gene (named Ccf-SoxN ) were identified in the genome of channel catfish Ictalurus punctatus . Identification of these genes is a potential step in understanding development regulations including sex determination in channel catfish. 相似文献
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Elizabeth C. Johnson Eric Hill Matthew A. Cooper 《International journal of primatology》2007,28(1):245-256
Researchers have not studied vomiting that is not associated with pathological behavior in nonhuman primates. Scientists generally
assume that vomiting provides protection by ejecting toxins from the body, but the explanation is not fully supported by the
literature. We report on 163 instances of vomiting from 2 groups of free-ranging bonnet macaques in southern India. The macaques
routinely reingested their vomit. The reingestion was unlike that in abnormal behavior of both humans and nonhuman primates.
We suggest that the tendency to hoard food in their cheek pouches explains why they reingested the vomit. 相似文献