Steroid receptor system

H)2D3 exerts its influence within target tissues through high-affinity sterol-specific intracellular receptor proteins. The D3 receptor, similar to steroid receptor systems, translocates the hormone from the cell cytoplasm to the nucleus, where biological response is initiated via transcription and translation (Fig. 66.3). 

Loose DS, Schurman DJ, Feldman D. A corticosteroid binding protein and endogenous ligand in C. albicans indicating a possible steroid-receptor system. Nature 1981 293 477. 

OT receptors in the hypothalamus are regulated by steroids. OT systems in the CNS are involved in homeostasis, reproduction, and related behavior. OT is also excitatory to neurons in the CNS at nanomolar concentrations (86), but relatively Httle is known about neuronal mechanisms and pharmacology. 

At the same time, there is evidence for membrane-associated steroid receptors that are coupled to second messenger systems (see below). 

Dittmar KD, Hutchison KA, Owens-Grillo JK, Pratt WB. (1996) Reconstitution of the steroid receptor.hsp90 heterocomplex assembly system of rabbit reticulocyte lysate. J Biol Chem. 271, 12833-12839. 

Multicomponent Hormonal Systems Facilitate a Great Variety of Responses The Guanylate Cyclase Pathway Calcium and the Inositol Trisphosphate Pathway Steroid Receptors Modulate the Rate of Transcription... 

DSL Diagnostic Systems Inc. (2005) Steroid hormone assays for clinical diagnostics and research applications. http //secure.dslabs.com/Products/ProdInfo.asp Lieberman BA (ed) (2001) Steroid receptor methods protocols and assays. Methods in molecular biology, vol 176. Humana Press, Totowa, NJ... 

Perhaps the environmental chemical most studied with regard to effects on the immune system has been 2,3,7,8-tetrachlorodibenzo-p-dioxin, which is also known as TCDD or dioxin . While it appears that dioxin may affect multiple cell types, it is apparent that the B cell is an especially sensitive target. The mechanism of action for the immunotoxic effects of dioxin remains poorly understood. It is well established that many of the actions of dioxin, including inhibition of the primary antibody response, are mediated by a specific cytosolic receptor, termed the aryl hydrocarbon receptor (AhR). AhR exhibits a profile of activity similar to steroid receptors in that the ligand-activated receptor undergoes a nuclear... 

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