Abstract
We have previously reported Cre/loxP recombination system which enables us region-specific expression of synaptopHluorin (SpH)1, one of green fluorescent protein-based sensors for vesicular exocytosis. Here we report another series of SpH transgenic lines in which SpH expression was regulated by the neuron specific Thy-1.2 promoter. In situ hybridization study revealed that SpH mRNA was expressed in broad spectrum of brain regions in 4 of them whereas in others it was expressed in the specific regions of hippocampus and cerebellum. SpH was preferentially expressed in the presynaptic elements of neurons. The SpH fluorescent intensity was somewhat decreased by acidic buffer surperfusion and greatly increased by vesicular neutralization of pH, indicating that they are mainly distributed in the synaptic vesicles. SpH fluorescence was transiently increased by neuronal activation. These transgenic lines are suggested to be useful for the morphological and physiological studies of presynaptic terminals in the brain.1. Araki, R. et al. Neuroscience Research 50S1 (2004) S124. [Jpn J Physiol 55 Suppl:S145 (2005)]
