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InvivoPharm is a preclinical contract research organisation (CRO) providing services in the general areas of
drug-receptor occupancy, radiolabeled drug distribution and
autoradiography.
Quantitative Whole-Body Autoradiography Service
Whole-body autoradiography produces an image of the
distribution of a radiolabeled test drug over the entire animal. Whole-body autoradiography is useful for determination of the following
drug distribution parameters:
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Sites of accumulation or retention of the drug,
including small organs and individual tissues
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Ability to cross blood-brain and placental barriers
or penetrate tumors
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Guiding toxicology studies
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Potential of radiopharmaceuticals for PET / SPECT
imaging and organ dosimetry
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Routes of elimination
In Vitro Autoradiography Service
In vitro autoradiography images the distribution of
radioactivity in the brain or other target organ following incubation of
cryostat-cut tissue sections in a radioactive drug. It can be used for
determining the distribution and density of drug receptors in the tissue
sections. It can also be used for competition-type assays, where
the IC50 for
a non-radioactive test drug to displace the receptor-binding of a
standard radiotracer to various regions-of-interest in the sections is
determined.
In Vivo Receptor Occupancy
Measures the degree to which the test drug actually
occupies its receptor in vivo. Receptor occupancy is determined by
measuring the ability of a systemic dose of the test drug
(non-radioactive) to compete with binding of a radiolabeled drug
to the receptor in vivo. Useful to determine the dose or plasma concentration
of the test drug needed to reach a therapeutically effective occupancy
level.
In Vitro Receptor Occupancy:
Radioligand Binding Assay
Radioligand (competitive) binding assays
determine the IC50 and Ki value for receptor-drug interactions in a
tissue homogenate by measuring the ability of the (non-radioactive) test
drug to compete with binding of a radiolabeled drug to the receptor.
Hot saturation assays using the radiolabeled ligand alone can be used to determine the density (Bmax) of the
receptor in the tissue. |