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Action of drugs that target carriers

4. Resources

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transport two molecules in opposite directions across the membrane.

ATP (adenosine triphosphate)

endogenous substance which occurs naturally within the body.

Allosteric inhibition (indirect)

where the carrier molecule is prevented from transporting the drug, when a different drug binds to a separate site on the carrier. This alters the three-dimensional structure of the binding site, preventing the binding of endogenous ligands.

Energy dependent

energy dependent carriers require energy in the form of ATP in order to transport molecules against a concentration gradient.


monoamine neurotransmitter and hormone synthesised from the amino acid tryptophan in serotonergic neurones in the central nervous system (CNS) and enterochromaffin cells in the gastrointestinal tract.


carry two different molecules in the same direction across the membrane.


carry a single molecule in one direction across the membrane.


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Reusable Learning Objects – School of Health Sciences, University of Nottingham

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Content authors: Chris Craggs, Kerry Welch

Project mentor: Richard Windle

Project developer: Lucrezia Herman

Repurposed by: Amanda Hill, Gill Langmack and Michael Taylor

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