What's a brain: neuroanatomy and neurochemistry of anxiety disorders in dogs

This review deals with the neurocircuitry of fear and anxiety disorders, with the focus on neuroanatomy and neurochemistry. This knowledge is required to correctly diagnose and treat dogs with anxiety-related behavioral disorders. Research to date has shown the involvement of the frontal cortex, the amygdala, the thalamus and the hippocampus as core regions in regulating fear. Imbalances (hyper- or hypoactivation) in this fear circuitry can trigger inappropriate fear responses, i.e. anxiety disorders. Serotonin, dopamine and norepinephrine are the main neurotransmitters of emotion in the brain, but gamma-aminobutyric acid (GABA), glutamate, and the hypothalamic-pituitary-adrenal (HPA) axis producing glucocorticoids are also important in the neurochemistry of anxiety

Functional brain imaging : a brief overview of imaging techniques and their use in human and canine anxiety research

When used in combination with specific radioactive markers, functional imaging modalities such as Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) enable the visualization of several neurotransmitter receptors and transporters, as well as of the perfusion and metabolism of the brain. This paper gives an overview of the functional imaging techniques, as well as of the studies that have been performed on humans and canines with anxiety disorders. Thus far, most of the research in this field has been focused on brain perfusion and the serotonergic and dopaminergic neurotransmitters, and less on gamma-aminobutyric acid (GABA), glutamate, norepinephrine and the hypothalamic-pituitary-adrenal (HPA) axis

Nuclear medicine: investigation of renal function in small animal medicine

Kidney function investigations in veterinary medicine are traditionally based on blood analysis (blood urea nitrogen (BUN) and serum creatinine concentration) and / or urinalysis (urine specific gravity, protein-to-creatinine ratio or fractional excretion). Morphologic information is usually obtained by abdominal radiography or ultrasonography. However, when more specific information on the functionality of the kidneys is needed, nuclear medicine offers various tracers that specifically represent glomerular filtration rate, effective renal plasma flow or functional renal mass, sometimes combining functional and morphologic data. These procedures can be based on blood sampling techniques (non-imaging methods), or data can be obtained using a gamma-camera (imaging methods). The most commonly used radionuclides for the examination of kidney function in small animal medicine are discussed in this review

Brain perfusion, part 2: anesthesia and brain perfusion in small animals

Sedatives and anesthetics can influence cerebral metabolism and respiratory and cardiovascular dynamics, which results in changes in cerebral perfusion. This is of major importance when functional brain imaging techniques are used to measure cerebral blood flow or to evaluate neurotransmitter systems, and also during neurosurgery. In the present review, the influences on brain perfusion of different sedatives including opioids and anesthetics commonly used in veterinary medicine are summarized