Adrenergic Neurons/drug effects; Adrenergic Uptake Inhibitors/pharmacology; Axons/drug effects; Desipramine/pharmacology; Norepinephrine Plasma Membrane Transport Proteins/metabolism; Prefrontal Cortex/drug effects; Tyrosine 3-Monooxygenase/metabolism; Adrenergic Neurons/metabolism; Adrenergic Neurons/ultrastructure; Adrenergic Uptake Inhibitors/administration & dosage; Adrenergic Uptake Inhibitors/blood; Animals; Antidepressive Agents, Tricyclic/administration & dosage; Antidepressive Agents, Tricyclic/blood; Antidepressive Agents, Tricyclic/pharmacology; Axons/metabolism; Axons/ultrastructure; Cell Membrane/drug effects; Cell Membrane/metabolism; Cell Membrane/ultrastructure; Desipramine/administration & dosage; Desipramine/blood; Immunohistochemistry; Infusion Pumps, Implantable; Male; Microscopy, Electron, Transmission; Nerve Tissue Proteins/metabolism; Prefrontal Cortex/metabolism; Prefrontal Cortex/ultrastructure; Protein Transport/drug effects; Rats; Rats, Sprague-Dawley; Reproducibility of Results; Synaptic Membranes/drug effects; Synaptic Membranes/metabolism; Synaptic Membranes/ultrastructure