Study Set Content:
Drug concentration and effects are described by a
(blank) curve (figure 2-1 A) according to the following
equation.
hyperbolic
Drug concentration and effects are described by a
hyperbolic curve (figure 2-1 A) according to the following
equation.
E = Emax x C/ C + EC 50
E is the
effect observed at concentration C,
E max is the
maximal response that can be produced by
the drug
EC 50 is the
the concentration of drug that produces 50%
of maximal effect.
To confirm the (blank) in many drug receptor
systems.
occupancy assumption
Drug bound to receptors (8) relates to the concentration of free
(unbound) drug (C) as depicted in Figure 2-1 B and as described by
an analogous equation:
B = Bmax x C/C + Kd
Which B max indicates the
total concentration of receptor sites
Which B max indicates the total concentration of receptor sites (ie.
sites bound to the drug at infinitely
high, concentration of free drug)
and Kd the
equilibrium dissociation constant .
(the equilibrium dissociation constant represents the (blank) of free drug at which (blank) is observed.
concentration, half-maximal binding
determined by “downstream” biochemical
events that transduce receptor occupancy into cellular
response.
Coupling
For some receptors, such as Ligand-gated Ion Channels,
the relationship between drug occupancy and response can
be simple because the ion current produced by the drug is
(blank) to the number of receptors (ion
channels) bound.
directly proportional
For other receptors, such as those linked to (blank), the occupancy-response
relationship is often more complex
enzymatic
signal transduction cascades
For other receptors, such as those linked to enzymatic
signal transduction cascades, the occupancy-response
relationship is often more complex because the (blank) response reaches a maximum before full receptor occupancy
is achieved.
biologic
bind to receptors but do not activate
them.
Receptor antagonist
2 types of antagonist
Competitive antagonist
o Noncompetitive antagonist
it binds reversibly to the same active site of an enzyme as
an agonist.
Competitive antagonist
in the presence of a fixed concentration of agonist, increasing
concentrations of a competitive antagonist will (blank) the
agonist response.
inhibit
HOW CAN A COMPETITIVE ANTAGONIST BE OVERCOME?
by increasing the (blank)(agonist).
The maximum efficacy of the drug will not change in the
presence of a competitive antagonist.
concentration of the drug
