Optical imaging of neurons is a useful tool for the study of neurotransmission. Fluorescent false neurotransmitters (FFNs) mimic the body's neurotransmitters and allow researchers to visualize neurotransmission simultaneously with other fluorescent markers. This technology revises FFNs so that they can be pH responsive by exploiting fluorescence characteristics. Since the secretory vesicles of neurons are pH driven researchers utilizing this technology may now visualize not only neurotransmission, but also optically measure pH levels of these secretory vesicles.
Previously, the only technologies that allowed researchers to visualize vesicular pH were cumbersome and time-consuming. For instance, in vitro visualization required transfections of vectors into cells, a technique that in large part fail to achieve very high efficiency. Moreover, transfections often kill cells and are difficult to succeed in ex vivo studies. Former in vivo experiments achieving optical measurements of pH could only be done via transgenic animal models, which can take years to generate, without guaranteed success. This technology offers a non-toxic, photostable, simple alternative: a pH-responsive, fluorescent false neurotransmitter. Cells incubated with the fluorescent compound showed selective uptake by VMAT vesicles, while pH measurements were performed using fluorescent microscopy, demonstrating the technology's ease of use.
This technology has been tested in vitro using PC12 cells.
Patent issued (WO2008013997 A3)
Tech Ventures Reference: IR M10-047