Acepromazine

Twelve weeks after surgery, the rats were deeply anesthetized with an intraperitoneal (IP) injection (300 ​mL) of a cocktail containing xylasin (3.2 ​mg/kg; Syntec, Cotia, SP, Brazil), ketamine (62.5 ​mg/kg; Syntec), and acepromazine (0.625 ​mg/kg; Syntec) diluted in water and perfused transcardially with a 0.9% saline solution for 10 ​min (10 ​mL/min, Masterflex®; Cole-Parmer Instrument Co.), followed by 4% paraformaldehyde (20 ​min) and 4% paraformaldehyde ​+ ​10% sucrose solution (10 ​min). The sciatic nerves or gastrocnemius muscles were kept in a 30% sucrose solution in phosphate buffer for 48 ​h. The nerves had the epineurium removed and were photographed under a stereomicroscope (Leica S8AP0; Leica Microsystems Nussloch GmbH). After embedding in OCT mounting medium, longitudinal sections of the sciatic nerves (18 ​μm) or gastrocnemius muscles (30 μm) were obtained using a cryostat (Leica CM 1850‘ Leica Microsystems Nussloch GmbH) and mounted directly on gelatin + 0.05% chromium alum precoated slides. Slides were stored at −20 ​°C for immunofluorescence procedures.

To perform the ovariohysterectomy, acepromazine (0.05 mg/kg IM) (acepromazine 2%; Syntec) and morphine (0.3 mg/kg IM) (morphine sulfate 10 mg/ml; Hipolabor + Sanval) were used as pre-anesthetic medication for healthy cats in diestrus, while meperidine (3 mg/kg IM) (Petidina; Uniao Chemical Laboratory) was used for cats with pyometra. For anesthetic induction, propofol (6 mg/kg IV) (Propotil; Biochimico) was used, with subsequent continuous infusion of Ringer’s lactate (6 ml/kg/h). The cats were intubated and anesthetic maintenance was performed with isoflurane (Isoforine; Cristália) in 100% oxygen (300 ml/kg/min) in an open circuit (Baraka) using an anesthesia machine (WATO EX-65; Mindray). Before the surgical procedure, the animals received sodium cephalothin (30 mg/kg IV) as prophylactic antibiotic therapy, even with all the proper aseptic conditions. Ovariohysterectomy was performed using the three-clamp technique after laparotomy through a midline incision.