TACR1 and acute pancreatitis: Different experimental approaches—gene knockout for substance P (pre-protachykinin-A—PPT-A gene) and its receptor [41] NK-1R, pharmacological inhibition of its action by using specific receptor antagonist [44], and inhibitors for neutral endopeptidase, the enzyme responsible for its inactivation [45] have been used to study the role of substance P in acute pancreatitis.