Examining the Role of Microbiota in Emotional Behavior: Antibiotic Treatment Exacerbates Anxiety in High Anxiety-Prone Male Rats

•Antibiotic treatment increased anxiety-like behavior in rats with innately high, but not low, anxiety-like behavior.•Proliferation of bacteria following antibiotic treatment differed between the rat strains.•Circulating leptin levels differed between rat strains before treatment, and treatment reduced leptin.•Antibiotic treatment altered blood–brain barrier permeability in a strain- and region-specific manner.