Enables serine-type endopeptidase inhibitor activity. Involved in several processes, including negative regulation of serine-type endopeptidase activity; positive regulation of secretion; and response to ethanol. Located in cytoplasm and extracellular space. Human ortholog(s) of this gene implicated in pancreatitis. Orthologous to human SPINK1 (serine peptidase inhibitor Kazal type 1). [provided by Alliance of Genome Resources, Apr 2022]