RECEPTORS Chapter

Lerma J (1999) Kainate receptors, chapter 8 Ionotropic glutamate receptors in the CNS. Springer Verlag... 

As an example, the low-density lipoprotein (LDL) molecule and its receptor (Chapter 25) are internalized by means of coated pits containing the LDL receptor. These endocytotic vesicles containing LDL and its receptor fuse to lysosomes in the cell. The receptor is released and recycled back to the cell surface membrane, but the apoprotein of LDL is degraded and the choles-teryl esters metabolized. Synthesis of the LDL receptor is regulated by secondary or tertiary consequences of pinocytosis, eg, by metabolic products—such as choles-... 

Despite the above precautions, it is still possible that NT spillover and extrasynaptic action may occur and indeed could be required in some instances. Thus the diffusion of glutamate beyond the synapse could activate extrasynaptic high-affinity NMDA or metabotropic receptors (Chapter 9) to produce long-lasting effects to maintain activity in a network. This may be important in long-term potentiation and memory effects. Crosstalk between synapses could also act as a back-up to ensure that a pathway functions properly (see Barbour and Hausser 1997). 

Know what properties turn a macromolecule into a drug receptor (chapter 2). 

Know how to design and synthesize a drug to fit into a receptor (chapter 3). 

Messenger targets drugs that target neurotransmitters and their receptors (chapter 4)... 

Ser/Thr (e.g. Thrl97 of PKA) or Tyr phosphorylation sites (see insulin receptor. Chapter 8) are located at the activation segment. As shown for the phosphorylation of the CDK2-cyclin A complex (see 13.2.4), phosphorylation in the activation segment leads to reorganization of the catalytic center in the sense of an optimal orientation of the catalytic groupings (review Johnson and O Reilly, 1996). 

Adenosine 5 -triphosphate is an excitatory neurotransmitter in the CNS and the peripheral nervous system (PNS). ATP acts via ionotropic P2X receptors (Chapter 3) and also acts through metabotropic G protein-linked P2Y receptors. With respect to P2Y receptors 1-13 that have been distinguished, uridine 5 -triphosphate (UTP) and ATP bind to P2Y2 and P2Y4 and ATP also binds to P2Y11. The signalling mechanism involves Gaq-mediated cytosolic Ca2+ elevation. 

Signalling is initiated by binding of Wnt-factors to the Wnt or Frizzled receptors. These receptors resemble remotely heptahelical, G-protein-coupled receptors (Chapter... 

Uptake of Ca + info cells, or release of this ion from intracellular stores, is a major regulatory mechanism in many if not all cells (see Section E). Mn + activates phosphoenolpyruvate carboxykinase (Eq. 13-46) and may be a regulator of gluconeogenesis. Iron controls the S5mthesis of ferritin and of transferrin receptors (Chapter 16). The specific metal ions present in many biological macromolecules are likely to participate in additional regulatory processes. 

All but a few of the thyroid effects that have been identified occur at the level of gene transcription, mediated by nuclear thyroid hormone receptors (Chapter 30). These effects have a longer latency period than for most steroids some of the relatively early responses show a latency period of several hours. 

Mechanisms of action of several types of membrane channels and pumps such as the acetylcholine receptor (Chapter 13)... 

---