Progress in neurobiology
-
Progress in neurobiology · Nov 2010
ReviewRasagiline: a novel anti-Parkinsonian monoamine oxidase-B inhibitor with neuroprotective activity.
Rasagiline (N-propargyl-1-(R)-aminoindan) is a novel, highly potent irreversible monoamine oxidase (MAO)-B inhibitor, anti-Parkinsonian drug. Rasagiline is effective as monotherapy or adjunct to L-Dopa for patients with early and late Parkinson's disease (PD). ⋯ Novel findings demonstrated that the major metabolite of rasagiline, 1-(R)-aminoindan has antioxidant and neuroprotective capabilities and thus, may contribute to the overt activity of its parent compound, rasagiline. This paper will review the earlier and present studies in the development of rasagiline for treatment of PD and discuss its pharmacology and applicable mechanism of action.
-
Progress in neurobiology · Dec 2009
ReviewThe thalamic nucleus submedius and ventrolateral orbital cortex are involved in nociceptive modulation: a novel pain modulation pathway.
Recently, a series of studies have given rise to and provided evidence for the hypothesis that the nucleus submedius (Sm) in the medial thalamus is involved in modulation of nociception. The Sm, ventrolateral orbital cortex (VLO) and the periaqueductal gray (PAG) constitute a pain modulatory pathway, activation of which leads to activation of the PAG-brainstem descending inhibitory system and depression of the nociceptive inputs in the spinal cord and trigeminal nucleus. ⋯ Opioid peptides, serotonin, dopamine, glutamate and their related receptors are involved in Sm- and/or VLO-mediated descending antinociception, and a GABAergic disinhibitory mechanism participates in mediating the antinociception induced by activation of mu-opioid receptors, serotonin 1(A) receptors, and dopamine D(2)-like receptors. This review describes these findings, which provide important new insights into the roles of the thalamus and cerebral cortex in descending pain modulation.
-
Several cellular and molecular mechanisms have been implicated in migraine pathophysiology including abnormal neuronal excitability and vascular events. Drugs from different pharmacological classes are used for migraine prophylaxis. These agents may normalize neuronal excitability by modulating distinct ionic channels and various neurotransmitter systems. ⋯ Promising results have recently been obtained for angiotensin converting enzyme inhibitors and angiotensin II type 1 receptor blockers. Some limited clinical findings have also been reported for atypical antipsychotic agents, nutritional supplements and also botulinum toxin. Targets of migraine preventive treatment are to reduce frequency and intensity of attacks and to decrease disability related to chronic headache.
-
Progress in neurobiology · Nov 2008
ReviewThe orbitofrontal cortex and beyond: from affect to decision-making.
The orbitofrontal cortex represents the reward or affective value of primary reinforcers including taste, touch, texture, and face expression. It learns to associate other stimuli with these to produce representations of the expected reward value for visual, auditory, and abstract stimuli including monetary reward value. The orbitofrontal cortex thus plays a key role in emotion, by representing the goals for action. ⋯ Top-down word-level cognitive inputs can bias affective representations in the orbitofrontal cortex, providing a mechanism for cognition to influence emotion. Whereas the orbitofrontal cortex provides a representation of reward or affective value on a continuous scale, areas beyond the orbitofrontal cortex such as the medial prefrontal cortex area 10 are involved in binary decision-making when a choice must be made. For this decision-making, the orbitofrontal cortex provides a representation of each specific reward in a common currency.
-
Progress in neurobiology · Sep 2008
ReviewNociceptive behavior in animal models for peripheral neuropathy: spinal and supraspinal mechanisms.
Since the initial description by Wall [Wall, P. D., 1967. The laminar organization of dorsal horn and effects of descending impulses. ⋯ In particular, the review emphasizes the importance of the reciprocal interconnections between the analgesic areas of the brainstem and the pain-related areas of the forebrain. The latter includes the cerebral limbic areas, the prefrontal cortex, the intralaminar thalamus and the hypothalamus and play a critical role in the control of pain considered as part of an integrated behavior related to emotions and various homeostatic regulations. We finally speculate that neuropathic pain, like extrapyramidal motor syndromes, reflects a disorder in the processing of somatosensory information.