GCG and pulmonary arterial hypertension: According to the physiopathological theory, when vasoactive substances present in the intestinal circulation (e.g., serotonin, histamine, estrogen, glucagon) bypass the liver without being metabolized and pass through a CPSS, this results in pulmonary arterial hypertension (PAH) caused by the induction of long-lasting pulmonary vasoconstriction [3, 4].