Stereotaxic Surgery for Intra-CeA Cannulation

Stereotaxic surgery was performed under semi-sterile conditions as previously described (De Jong et al., 2014 (link); Oliveira et al., 2021 (link)). Briefly, rats were anesthetized with isoflurane, injected i.p. with the analgesic Buprenovet (0.05 mg/kg Buprenorphine, Bayer, Germany) and the antibiotic Baytril (10 mg/kg Enrofloxacin, Baytril, Bayer, Germany), and mounted in the stereotaxic frame. Intra-CeA (AP: -2.5; ML: ±4.0; DV: +6.0) guide cannulas (25 G, 12 mm; Injecta GmbH, Germany) were implanted bilaterally, 2 mm above the target region to avoid lesioning. Local cannulas were fixed to the skull with two jeweler’s screws and dental cement (Kallocryl, Speiko-Dr. Speier GmbH, Muenster, Germany) and closed by a stainless steel stylet (27 G). Cannulated females were left single-housed and undisturbed for 5 days to recover, prior to the start of the aggression training protocol.