Which of these hormones can easily pass through a plasma cell membrane and bind to a receptor within the cell?
Signal transduction Show
Types of signaling molecules and the receptors they bind to on target cells. Intracellular receptors, ligand-gated ion channels, G protein-coupled receptors, and receptor tyrosine kinases. Signal transduction
Review Plasma membrane transport of thyroid hormones and its role in thyroid hormone metabolism and bioavailabilityG Hennemann et al. Endocr Rev. 2001 Aug. AbstractAlthough it was originally believed that thyroid hormones enter target cells by passive diffusion, it is now clear that cellular uptake is effected by carrier-mediated processes. Two stereospecific binding sites for each T4 and T3 have been detected in cell membranes and on intact cells from humans and other species. The apparent Michaelis-Menten values of the high-affinity, low-capacity binding sites for T4 and T3 are in the nanomolar range, whereas the apparent Michaelis- Menten values of the low-affinity, high-capacity binding sites are usually in the lower micromolar range. Cellular uptake of T4 and T3 by the high-affinity sites is energy, temperature, and often Na+ dependent and represents the translocation of thyroid hormone over the plasma membrane. Uptake by the low-affinity sites is not dependent on energy, temperature, and Na+ and represents binding of thyroid hormone to proteins associated with the plasma membrane. In rat erythrocytes and hepatocytes, T3 plasma membrane carriers have been tentatively identified as proteins with apparent molecular masses of 52 and 55 kDa. In different cells, such as rat erythrocytes, pituitary cells, astrocytes, and mouse neuroblastoma cells, uptake of T4 and T3 appears to be mediated largely by system L or T amino acid transporters. Efflux of T3 from different cell types is saturable, but saturable efflux of T4 has not yet been demonstrated. Saturable uptake of T4 and T3 in the brain occurs both via the blood-brain barrier and the choroid plexus-cerebrospinal fluid barrier. Thyroid hormone uptake in the intact rat and human liver is ATP dependent and rate limiting for subsequent iodothyronine metabolism. In starvation and nonthyroidal illness in man, T4 uptake in the liver is decreased, resulting in lowered plasma T3 production. Inhibition of liver T4 uptake in these conditions is explained by liver ATP depletion and increased concentrations of circulating inhibitors, such as 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid, indoxyl sulfate, nonesterified fatty acids, and bilirubin. Recently, several organic anion transporters and L type amino acid transporters have been shown to facilitate plasma membrane transport of thyroid hormone. Future research should be directed to elucidate which of these and possible other transporters are of physiological significance, and how they are regulated at the molecular level. Similar articles
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Which type of hormone can easily pass through the plasma membrane?Steroid hormones can pass through the plasma membrane by simple diffusion because they are lipid derived hormones, which means that they are capable of passing through every cell of our body. Unlike other types of hormones, steroid hormones do not have to bind to plasma membrane receptors.
Which of the following hormones can pass through the plasma membrane and bind to a receptor within the cell?Final answer: Cortisol and testosterone are examples of those hormones that can easily pass through the cell membrane of the target cell and bind to the receptor inside it (mostly in the nucleus).
What hormones bind to receptors on the plasma membrane?The amino acid-derived hormones epinephrine and norepinephrine bind to beta-adrenergic receptors on the plasma membrane of cells. Hormone binding to receptor activates a G-protein, which in turn activates adenylyl cyclase, converting ATP to cAMP.
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