http://journals.ohiolink.edu/ejc/article.cgi?issn=10436618&issue=v53i0001&article=62_ppparatnj Pharmacological Research, Volume 53, issue 1 (January, 2006), p. 62-68 ISSN: 1043-6618, DOI: 10.1016/j.phrs.2005.09.002 Prion protein potentiates acetylcholine release at the neuromuscular junction Re, Lamberto1 e-mail; Rossini, Francesca1; Re, Francesco1; Bordicchia, Marica1; Mercanti, Alessandra1; Fernandez, Olga Sonia Leon2; Barocci, Simone3 Laboratory of Pharmacological Biotechnology, School of Biological Sciences, University of Ancona, Via Ranieri, 2, 60131 Ancona, Italy Center for Research and Biological Evaluation (CIEB-IFAL), University of Havana, Havana City 10400, Cuba Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche, Perugia 06126, Italy Cellular prion protein (PrPc), the normal isoform of the pathogenic peptide (PrPsc) responsible of the transmissible spongiform encephalopaties (TSEs), is present in many neural tissues, including neuromuscular junctions (NMJ). To analyze if this protein could influence the synaptic transmission, we performed an electrophysiological approach to study the effect of cellular prion protein on a mammalian neuromuscular junction. The loose patch clamp (LPC) technique enables the study of the whole preparation including the pre- and the post-synaptic domains. In a mouse phrenic–diaphragm preparation, nanomolar concentrations of cellular prion protein were able to induce a very striking potentiation of the acetylcholine (ACh) release. The effect was mainly pre-synaptic with an increase of the amplitude of the miniature end-plate currents, probably calcium dependent. Moreover, an apparent facilitation of the synaptic transmission was noted. The results clearly indicate that cellular prion protein may play a key role in the function of the neuromuscular junction.