MATERIALS AND METHODS Rat Experiment Animals. Twelve female Sprague-Dawley rats (Harlan Laboratories, Venray, The Netherlands), weighing 250�C300 g, were used. The rats were acclimatized to the animal facility for at least 1 wk. Rats were housed in groups of five in an enriched environment with free access http://www.selleckchem.com/products/Bicalutamide(Casodex).html to food (standard pellets, R3, Lactamin, Kimstad, Sweden) and water on a 12:12-h light-dark cycle. The estrous stage of the rats was not accounted for in the present study. All experiments were approved by the local animal ethics review committee in G?teborg, Sweden (403-2008) and conducted at AstraZeneca, M?lndal, Sweden. Surgery. Prior to surgery, rats were administered antibiotics (1 ml/kg) (Bactrim, Oral 40/8 mg/ml, Roche, Basel, Switzerland) and analgesic (10 mg/kg) (Romefen, Merial Norden, Skovlunde, Denmark).

Rats were anesthetized with isoflurane (2�C3 vol%) (Forene, Abbott Scandinavia, Solna, Sweden) and kept on a heating pad during surgery to maintain body temperature. Surgical procedures consisted of implantation of skull electrodes and positioning of an abdominal connector. A midline scalp incision was made and the abdominal cavity was exposed by a 5-cm midline incision. From the abdominal cavity, Teflon-coated stainless steel cables (? = 0.3 mm; Cooner Wire, Chatsworth, CA) were passed through the abdominal musculature and tunneled subcutaneously across the thorax to the incision on top of the head. Two centimeters lateral to the abdominal incision a small plastic connector (AstraZeneca) was exteriorized and sutured to the abdominal wall to allow future access to the electrode cables.

The abdominal incision was closed and the rats were then placed in a stereotaxic frame. A few drops of lidocaine (Xylocaine iv, 20 mg/ml, AstraZeneca, S?dert?lje, Sweden) were applied to the scalp incision and connective tissue was scraped away from the skull surface. After exposure of the skull, a small hole (?0.9 mm) was drilled on each of the electrode positions and cables were secured by titanium electrodes (?0.9 mm, Wennbergs finmek, Gunnilse, Sweden) into these positions. Three electrodes for monopolar recordings were placed on the right side of the skull (Fig. 1A); the positions were selected based on experience from a previous study (23). Briefly, three electrodes were placed 1.5 mm lateral to the sagittal line. The most anterior electrode was placed 1.

5 mm anterior to bregma and the following two electrodes in a rostrocaudal direction, separated by 3 mm (Fig. 1A). The reference electrode was positioned 2 mm caudal to lambda. Fig. 1. A: positioning of recording electrodes Brefeldin_A on the rat skull. B: schematic drawing of the experimental protocol used in the rat study. C: schematic drawing of the experimental protocol used in the human experiment. Electrodes were placed avoiding penetration of the underlying dura mater.