Neurotransmitter agonists

Receptor Broadly applied to the molecular site of drug action. More specifically, this term describes the plasma membrane proteins to which neurotransmitters, agonists and antagonists bind. 

There is a space that exists between neurons known as the synapse. The transmission of the nerve signal across this synaptic cleft is a chemical phenomenon. Molecules generically referred to as neurotransmitters are produced in the neuron and released from the axonal membrane into the synapse. They diffuse to the dendrites of the next nerve cell and combine with receptors. This combination of neurotransmitter (agonist) and receptor produces a response which results in the propagation of the nerve signal down the next neuron. We will discuss this activity in much more detail shortly. 

This means that there is a spectrum of degree to which a receptor can be stimulated (Fig. 3 — 14). At one end of the spectrum, there is the full agonist, which elicits the same degree of physiologic receptor-mediated response as the natural neurotransmitter agonist itself. At the other end of the spectrum is a full inverse agonist, which in concept does the opposite of the agonist. In the middle is the... 

The ergolines have provided a number of drugs that show interaction with neurotransmitters. Depending on the substitution pattern, they may be dopamine agonists or antagonists, a-adrenergic blockers, or Inhibitors of the release of prolactin. A recent member of the series, pergolide... 

Natural or synthethic receptor ligands that induce a conformational change (active conformation) and a signal transduction process upon receptor binding. Agonists may act as typical hormones or neurotransmitters or they may confer paracrine functions, recognize bacterial, viral or other environmental constituents via activating their dedicated receptors. 

GABA is the predominant inhibitory neurotransmitter in the CNS. Baclofen acts centrally as an agonist at the GABAb receptor, which increases inhibition of nerves. 3-Aminopropylphosphinic acid (3-APPi) has been shown experimentally to act as an antitussive at peripheral nerves and preclinical evidence suggests that baclofen indeed has antitussive actions clinically [3]. 

A medication that causes induction of sleep. The majority of currently available hypnotics (for example benzodiazepine receptor agonists) act via potentiating the brain s inhibitory GABAergic systems, in turn reducing the activity of arousal (i.e. wake promoting) neurotransmitter systems. 

A 17 amino acid long peptide sequentially related to opioid peptides in particular dynorphin A. OFQ/N is inactive at the 5, k, and p opioid receptors, but binds to its own NOP receptor (formerly ORL-1, for opioid receptor like-1). In contrast to opioid peptides, OFQ/N has no direct analgesic properties. OFQ/N is the first example for the discovery of a novel neurotransmitter from tissue extracts by using an orphan receptor as bait. Centrally administered in rodents, OFQ/N exerts anxiolytic properties. OFQ/N agonists and antagonists... 

GABA is the most prominent inhibitory neurotransmitter in the mammalian nervous system and acts via GABA receptors. Activation of GABAb receptors by GABA released from local spinal interneurons (Fig. 1) negatively modulates nociceptive transmission in the spinal cord. Agonists at GABAb receptors... 

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