It was already know that the peptide fragment CCK-4 reliably causes sever panic panic attack when administered in doses of 50 μg. And CCK4 is fragment of an hor

It was already know that the peptide fragment CCK-4 reliably causes sever panic panic attack when administered in doses of 50 μg. And CCK4 is fragment of an hormone produced by the duodenum. If the small intestine can trigger a panic attack, it's not that surprising that other organs can also create anxiety.