Vesicular monoamine transporter, isoforms

Weihe E, Schafer MK, Erickson JD, Eiden LE (1994) Localization of vesicular monoamine transporter isoforms (VMAT1 and VMAT2) to endocrine cells and neurons in rat. J Mol Neurosci 5 149-164. 

The norepinephrine transporter (NET) and the vesicular monoamine transporter (VMAT) are presynaptic components of the sympathetic neurons. NET is a Na+ /Cl -dependent transport protein and responsible for the neurotransmitter uptake from the synaptic cleft into the cytoplasm of the neurons. This transport process, called uptake-1, reduces the amount and, thus, the effect of NE released into the synaptic cleft. NE is stored in the cytoplasm of the neurons in specialized vesicles by the H+-dependent transport protein VMAT. Two isoforms VMAT1 and VMAT2, are known. VMAT is localized in the vesicle membranes, and the vesicular storage protects NE from metabolism by monoamine oxidase (MAO), which is localized on the surface membrane of the mitochondria. Vice versa, nerve depolarisation causes NE release from the vesicles into the synaptic cleft by Ca+-mediated exocytose (Fig. 12) [79,132-136],... 

Erickson JD, Schafer MK, Bonner TI, Eiden LE, Weihe E (1996) Distinct pharmacologicalal properties and distribution in neurons and endocrine cells of two isoforms of the human vesicular monoamine transporter. Proc Natl Acad Sd US A 93 5166-5171. 

Erickson JD, Eiden LE, Hoffman BJ (1992) Expression cloning of a reserpine-sensitive vesicular monoamine transporter. Proc Natl Acad Sci USA 89 10993-10997 Erickson JD, Schafer MK, Bonner TI, Eiden LE, Weihe E (1996) Distinct pharmacological properties and distribution in neurons and endocrine cells of two isoforms of the human vesicular monoamine transporter. Proc Natl Acad Sci USA 93 5166-5171 Faham S, Watanabe A, Besserer GM, Cascio D, Specht A, Hirayama BA, Wright EM, Abramson J (2008) The crystal structure of a sodium galactose transporter reveals mechanistic insights into Na+/sugar symport. Science 321 810-814... 

Anlauf, M., Eissele, R., Schafer, M.K., Eiden, L.E., Arnold, R., Pauser, U., et al. Expression of the two isoforms of the vesicular monoamine transporter (VMATl and VMAT2) in the endocrine pancreas and pancreatic endocrine tumors. The Journal of Histochemistry and Cytochemistry Official Journal of the Histochemistry Society 51, 1027-1040(2003)... 

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