This study provides evidence of persistent biochemical change of the hypothalamus in patients with episodic cluster headache. Low levels of NAA/Cr and Cho/Cr suggest that cluster headache might be related to both neuronal dysfunction and changes in the membrane lipids in the hypothalamus.Read More →
The neuropeptide calcitonin gene-related peptide (CGRP) has long been postulated to play an integral role in the pathophysiology of migraine. While clinical findings are consistent with such a role, the specific pathogenic mechanisms of CGRP in migraine have remained speculative until recently. Through advances in molecular neuroscience, the pathogenic mechanisms of CGRP in migraine have begun to be elucidated. This paper discusses the hypothesized role of CGRP in migraine and reviews recent findings on the molecular mechanisms of this neuropeptide in migraine pathophysiology. Studies in cultured trigeminal neurons demonstrate that CGRP is released from trigeminal ganglia cells, that CGRP transcription is increased under conditions mimicking neurogenic inflammation, that migraine pharmacotherapies can both reduce CGRP release and inhibit CGRP transcription, and that tumor necrosis factor-α (TNF-α), an endogenous inflammatory mediator implicated in migraine, can stimulate CGRP transcription. Read More →
You interview a “migraine” sufferer who hopes to find the relief that has so far eluded him. During the history taking, he reports experiencing the premonitory aura typical of migraine as well as photophobia and occasionally nausea. One description, though, raises a question about the cause of his headaches: he says the intense pain recurs at roughly the same time of day and lasts for about 45 minutes; he is unable to concentrate on anything but the pain and he paces ceaselessly until it abates. The odds now favor a diagnosis of cluster headache.Read More →
Vanilloid receptor 1 (TRPV1) is activated by chemical ligands and heat. In this study, we found that each of the group B antagonists competed with and prevented BCTC, AMG6880 or AMG7472 antagonism of rat TRPV1 activation by protons with pA2 values similar to those for blocking capsaicin, indicating that proton activation does not alter the conformation of the TRPV1 capsaicin-binding pocket. In conclusion, group A antagonists seem to lock the channel conformation in the closed state, blocking both capsaicin and proton activation.Read More →
Cluster headache is a stereotyped primary pain syndrome characterised by strictly unilateral severe pain, localised in or around the eye and accompanied by ipsilateral autonomic features. The syndrome is characterised by the circadian rhythmicity of the short-lived attacks, and the regular recurrence of headache bouts, which are interspersed by periods of complete remission in most individuals. Read More →
Cluster headache is a stereotyped primary pain syndrome characterised by strictly unilateral severe pain, localised in or around the eye and accompanied by ipsilateral autonomic features. The syndrome is characterised by the circadian rhythmicity of the short-lived attacks, and the regular recurrence of headache bouts, which are interspersed by periods of complete remission in most individuals.Read More →
Abstract
Drosophila melanogaster flies carrying the trp (transient receptor potential) mutation are rapidly blinded by bright light, because of the absence of a Ca2+-permeable ion channel in their photoreceptors. The identification of the trp gene and the search for homologs in yeast, flies, worms, zebrafish and mammals has led to the discovery of a large superfamily of related cation channels, named TRP channels. Activation of TRP channels is highly sensitive to a variety of chemical and physical stimuli, allowing them to function as dedicated biological sensors that are essential in processes such as vision, taste, tactile sensation and hearing.Read More →