The clinical use of morphine to reduce pain is limited because of its drug tolerance, dependence and addiction. In the present study, the tree shrews (Tupaia belangeri chinensis) developed morphine tolerance and chronic morphine dependence by morphine injections with increasing doses (5, 10, 15, 20 mg/kg body weight for 7 days). Meanwhile, the naloxone (1.25 mg/kg body weight)-induced condition...

Much attention has been payed to tree shrews for their close phylogenetic relationship with primates, small size, and short reproductive cycle. Especially, they are considered as excellent experiential animals for medicine or/and disease research. A nucleotide sequence encoding neuropeptide Y(NPY) precursor has been cloned from the cDNA library of Tupaia belangeri chinensis. Sequence alignment ...

While searching for potential candidate molecules relevant for the pathogenesis of endometriosis, we discovered a 2910-base pair cDNA encoding a novel putative 411-amino acid integral membrane protein that we called shrew-1. The putative open-reading frame was confirmed with antibodies against shrew-1 peptides that labeled a protein of approximately 48 kDa in extracts of shrew-1 mRNA-positive t...

While searching for potential candidate molecules relevant for the pathogenesis of endometriosis, we discovered a 2910 bp cDNA encoding a novel putative 411 amino acid integral membrane protein which we called shrew-1. The putative open-reading frame was confirmed with antibodies against shrew-1 peptides which labelled a protein of ca. 48 kDa in extracts of shrew-1 mRNA positive tissue and also...

While most mammalian retinas are rod dominated, in the tree shrew retina 95% of the photoreceptors are cones. We studied three shrew horizontal cells to look for features associated with this unusual photoreceptor arrangement. The morphology of horizontal cells was revealed by intracellular injections of Lucifer yellow, and their photoreceptor contacts were assessed by light and electron micros...

Tree shrews are small mammals living in the tropical forest of Southeast Asia. The habitus of species within the genus Tupaia is often quite similar, so that it is difficult to differentiate the species based on their morphology. We applied comparative bioacoustics, a tool successfully used to discriminate cryptic species of nocturnal mammals, to investigate whether species in the diurnal genus...

Intrinsic connections within the tree shrew (Tupaia glis) visual cortex (area 17) are organized in periodic stripelike patterns within layers I, II, and III. This anatomical network resembles the regularly organized stripes of 2-deoxyglucose accumulation seen after stimulation of alert animals with uniformly oriented lines. Such connections imply that widespread lateral interactions are superim...