Downregulation, receptor

Selective estrogen receptor downregulators (SERDs) is a class of medication that induces an estrogen receptor downregulation. 

The regulation of receptor synthesis is a second component of receptor downregulation. It involves processes that reduce gene transcription, mRNA stability, and receptor half-life time. It should be noted that mechanisms in addition to the regulation of the receptor number may account for tolerance development. Second messenger levels and enzyme activities that participate in the signaling of a given receptor are... 

Miller LG, Greenblatt DJ, Barnhill JG, et al Chronic benzodiazepine administration, I tolerance is associated with benzodiazepine receptor downregulation and decreased gamma-aminobutyric acidA receptor function. J Pharmacol Exp Ther 246 170-176, 1988a... 

COMMENT It seems to me that, in the absence of the serotonin input, the 5-HT2 serotonin receptors downregulate instead of upregulate. So if you... 

LHRH, luteinizing hormone-releasing hormone SERD, selective estrogen receptor downregulator SERM, selective estrogen receptor modulator. 

Swanson, K. A., Kang, R. S., Stamenova, S. D., Hicke, L., and Radhakeishnan, 1. Solution structure of Vps27 UlM-ubiquitin complex important for endosomal sorting and receptor downregulation. Embo J 2003, 22, 4597-606. 

Analogous to b-adrenergic receptor downregulation, antidepressants reduce 5-HT receptor number but not their affinity (51). 

Preliminary results from case reports, case series, and open and increasingly better controlled trials have found TMS to be effective in the treatment of depression. TMS, antidepressants, and ECS appear to induce similar effects in animal behavioral models of depression and changes in brain neurochemical activity. These include changes in the forced swim test, increase in seizure threshold, and effects on b-noradrenergic receptor downregulation. Whereas seizures appear unnecessary to achieve clinical benefit with TMS, it is still unclear what aspects are beneficial. As noted earlier, although this modality is associated with some complications (e.g., headaches and, rarely, inadvertent seizure) relative to ECT and perhaps even pharmacotherapy under certain situations, it appears to be quite safe. Future studies of major depression should explore TMS-related issues such as the following ... 

Uotani, S., Bjorbaek, C., Tomoe, J., and Flier, J. S. 1999. Functional properties of leptin receptor isoforms internalization and degradation of leptin and ligand-induced receptor downregulation. Diabetes 48 279-286. 

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