Membrane Transport Filtration

Membrane Transport

**Filtration** Pharmacology for dummies

Filtration • Drugs can pass through [Filtration] pores in membrane or paracellular spaces as in capillary endothelium capillarry endothelium • These pores can be large as in endothelium or very ‘Tight” as in brain[blood brain barrier] • Lipid insoluble drugs, small enough can pass through these pores • [Lipid soluble pass by passive diffusion as discussed earlier] • It is rate of blood flow across capillaries decides rate of filtration rather than pH and lipid solubility [Which are important for passive diffusion] Pharmacology for dummies

Questions • The statement which is wrong about filtration as a process of drug transport across biological membranes is a) Drugs pass through aqueous pores in membranes b) Drugs pass through paracellular spaces c) It is dependent on lipid solubility of a drug d) It is dependent on rate of blood flow through capillaries Answer: ‘c’ Pharmacology for dummies