|Appears in Collections:||Psychology Journal Articles|
|Peer Review Status:||Refereed|
|Title:||Non-competitive metabotropic glutamate 1 receptor antagonists block activity of slowly adapting type I mechanoreceptor units in the rat sinus hair follicle|
Mavulati, S C
|Keywords:||Merkel nerve endings|
metabotropic glutamate receptors
slowly adapting mechanoreceptors
|Publisher:||Elsevier / International Brain Research Organization (IBRO)|
|Citation:||Cahusac P & Mavulati SC (2009) Non-competitive metabotropic glutamate 1 receptor antagonists block activity of slowly adapting type I mechanoreceptor units in the rat sinus hair follicle, Neuroscience, 163 (3), pp. 933-941.|
|Abstract:||Previous studies suggested that Group I metabotropic glutamate (mGlu) receptors play a role in mechanotransduction processes of slowly adapting type I mechanoreceptors. Using an isolated rat sinus hair follicle preparation we tested a range of compounds. Surprisingly, only non-competitive mGlu1 receptor antagonists produced profound and long-lasting depression of mechanically evoked firing. 6-Amino-N-cyclohexyl-N,3-dimethylthiazolo[3,2-α]benzimidazole-2-carboxamide hydrochloride (YM-298198) had an IC50 of 8.7 μM (95% CI 5.7 to 13.2 μM), representing the most potent known blocker of type I mechanoreceptors. The derivative 6-amino-N-cyclohexyl-3-methylthiazolo[3,2-α]benzimidazole-2-carboxamide hydrochloride (desmethyl YM-298198) had a comparable potency. Another compound 7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxylate ethyl ester (CPCCOEt) had a similar depressant effect, although it was less potent with an approximate IC50 of 100 μM. Between three and seven times the concentration of CPCCOEt and YM-298198 respectively was required to produce similar depressions in slowly adapting type II units. No depression, and some weak excitatory effects, were observed using the following ligands: the competitive mGlu1 receptor antagonist α-amino-5-carboxy-3-methyl-2-thiopheneacetic acid (3-MATIDA) (300 μM), the phosphoserine phosphatase inhibitor dl-2-amino-3-phosphonopropionic acid (dl-AP3) (2 mM), non-competitive mGlu5 receptor antagonists 3-((2-methyl-1,3-thiazol-4-yl)ethynyl)pyridine; (S)-3,5-DHPG, (S)-3,5-dihydroxyphenylglycine (MTEP) (10 μM) and 2-methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP) (100 μM), the mGlu1 receptor agonist (S)-3,5-dihydroxyphenylglycine ((S)-3,5-DHPG) (500 μM), and the mGlu5 receptor agonist (RS)-2-chloro-5-hydroxyphenylglycine (CHPG) (1 mM). The results suggest that the non-competitive mGlu1 receptor antagonists are not acting at conventional mGlu1 receptors but at other binding sites, possibly those directly associated with mechanogated channels or on any of a number of indirect biochemical pathways. YM-298198 and related compounds may prove to be useful ligands to identify mechanosensitive channel proteins. The selective interference of type I units may provide further evidence that Merkel cells are mechanotransducers. Finally such compounds may deliver insights or treatments for Merkel cell carcinoma.|
|Rights:||The publisher does not allow this work to be made publicly available in this Repository. Please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author; you can only request a copy if you wish to use this work for your own research or private study.|
Glasgow Caledonian University
|Cahusac4.pdf||835.62 kB||Adobe PDF||Under Embargo until 31/12/2999 Request a copy|
Note: If any of the files in this item are currently embargoed, you can request a copy directly from the author by clicking the padlock icon above. However, this facility is dependant on the depositor still being contactable at their original email address.
This item is protected by original copyright
Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
If you believe that any material held in STORRE infringes copyright, please contact firstname.lastname@example.org providing details and we will remove the Work from public display in STORRE and investigate your claim.