Angiotensin 1–7 increases quantal content and facilitation at the frog neuromuscular junction

At the neuromuscular junction, several endogenous substances have been shown to act presynaptically to modify transmitter release. Here we show that angiotensin 1–7, a vasoactive peptide of the renin–angiotensin system, increased quantal content in a dose-dependent manner, with a maximal increase of 78% at 250 nM. At the same dose, angiotensin 1–7 increased paired pulse facilitation by 70%. This is the first report of angiotensin 1–7 altering a cholinergic synapse.