Kategóriák: Minden - receptors - drugs - administration - pharmacokinetics

a Michayla Erasmus 1 éve

105

Pharmacokinetics and Pharmacodynamics

The text discusses the roles of various receptors in the body, specifically focusing on alpha and beta receptors. Alpha receptors are divided into Alpha 1 and Alpha 2, primarily found in vascular smooth muscles and effector tissues.

Pharmacokinetics and Pharmacodynamics

Pharmacokinetics and Pharmacodynamics

Secondary Pathway receptors

Beta Receptors This refers to a group of receptors that relax the effector cells. They control vasodilation and relaxation of uterine muscles. They also increase the heart rate. There are also three types of beta cells. Beta 1, beta 2 and beta 3 receptors.These receptors are mainly found in cardiac muscles and bronchi muscles. Albuterol is and example of a beta 1 and metoprolol is an example of beta 2.
Alpha Receptors These are receptors that stimulate effector cells. These control physiological processes such as vasoconstriction, intestinal relaxation or pupil dilation. There are two types of alpha receptors : Alpha 1 and Alpha 2. These are mainly found in vascular smooth muscles or effector tissues. Methoxamine is an alpha 1 agonist and Clonidine is an alpha 2 agonist.

Pharmacodynamis This is the pharmalogical effect of the drug molecule on the body, this being the biochemical and physiological effects of drugs and the mechanisms of their actions. It comprises usually of receptor binding or non-specific action which leads to a pharmalogical effect.

Receptor Classifications
Enzyme receptors Situated on enzymes and inhibit their functions

Transport-carrier receptors Situated on carriers in the cell membranes and also carry drugs across the cell membrane.

Storage receptors These receptors are present in nerve endings

Plasma protein receptors These receptors are situated on plasma proteins such as Albumin

Therapeutic and/or side effects of drugs

Metabolism and Absorption Each individual has a different metabolic rate which essentially means that some people break down food or substances faster than others. If a drug is metabolized fast then the person may not experience andy effect of the medication.
Tolerance After some time, of using a drug a persons body becomes or develops a tolerance to the drug and in some cases the drug may become ineffective
Mental state or capacity The state of a persons mentality also has a really large effect on their response to a drug.
Age Children and the elderly might have more sensitivity to drugs
The Dosage The effects can vary a lot depending on how much is given or administered. A small dosage might have little to no effect on a patient. A higher dosage there may be different behavioural responses and in extreme cases it can cause death
Method of Administration The way in which medications are administered greatly affect how they work, the intensity and the duration. Some drugs can also only be administered a certain way.
Type of drug There are different types of drugs and these produce many different responses

Classification of Drugs

Antagonist A drug with affinity but with no intrinsic activity for the receptor, binding with the receptor without essentially activating the receptor. It counteracts the action of the receptor. An example would be Beta Blockers.
Partial Agonist These are drugs that bind to and activate a given receptor but are only able to have a partial effiicacy at the receptor relative to the agonist. An example is Buprenorphine
Agonist A drug with affinity and intrinsic activity for the receptor and is able to activate the receptor upon binding. This meaning the drug binds with a receptir and results in an effect. An example is Acetylcholine

Pharmacokinetics This is when a drug is administered, it is first absorbed at the site and then absorbed into the bloodstream. It refers to the study of how a drug is absorbed, distributed, metabolized and eliminated withing the body.