Question

10. What class of proteins play a critical role in 0 pharmacokinetics but not in phase 3? Name the 2 major superfamilies of this class of proteins? What is the role of these proteins and how do they impact pharmacokinetics and/or pharmacodynamics? Provide an example of a gene encoding this class of protein in which polymorphism impacts both irinotecan and digoxin response. Q11. Define pharmacodynamics and list 3 physiological mechanisms by which this might be achieved

Answer 1

Q10, The plasma protein binding drugs have drug concentration in pharmacokinetics necessary for effective therapeutic monitoring..
Superfamily:
Albumin is the main protein of plasma it binds water,cations,fatty acids,hormones,bilirubin and drugs its main function to regulate the colloidal osmotic pressure of blood..
Alphafeto-protein is a foetal plasma protein that binds cations,fatty acids and bilirubin..
Role of plasma binding protein:
  Changes in plasma protein binding due to drug interactions,disease effects,genetic factors affect drug pharmacokinetics..changes in plasma protein binding may or may not be depends on unbound drug exposure that is change the alterations of protein bindings..Determination of drug plasma binding affecting this process by providing mechanistic view into drug displacement interaction or unusual pharmacokinetics character..
Example:
Drug response to each individual determined by the pharmacokinetics and pharmacodynamic properties of prescribed drugs,it will be affected by polymorphisms in drug metabolizing enzymes and transporters..presence of genetic polymorphism in genes encoding these proteins associated with inter-individual variability can result in drug variation ,toxicity and disease predisposition..These pharmacokinetics helps to find disease risk,selection of proper medication based on person genetic makeup..
Example: CYP2D6 is responsible for metabolism of drugs like digoxin..it involve in 2-4 percent involved in elimination of 25% currently prescribed drugs..It is highly polymorphic..It results in a increased concentration of the parent drugs in plasma,result in gene duplication leads to increased enzyme activity,resulting in less drug concentration in blood..