Question | Answer |
Alpha Receptors | Activates enzymes inside plasma membrane. |
Alpha 1 | Releases intracellular calcium ions into the cytosol from reserves in endoplasmic reticulum. Causes vasoconstriction, increased contractile force, decreasing heart rate, bronchoconstriction. |
Alpha 2 | Lowers cyclic AMP (cAMP) levels in cytoplasm. cAMP is a 2nd messenger that can activate/inactivate key enzymes. Vasodilatation, decreases blood pressure, in targeted organs, coronary arteries. |
Beta Receptors | Located in membranes of cells in organs, including skeletal muscles, lungs, heart, liver. Changes metabolic activity in cell by stimulation, resulting in increase in intracellular cAMP levels. |
Beta 1 | Increases metabolic activity, in skeletal muscles, accelerates in the heart, increase in heart rate and contraction force. |
Beta 2 | Causes inhibition, triggering a relaxation of smooth muscles along respiratory tract, respiratory passageways open, making breathing easier. Bronchodilation. |
Beta 3 | Stimulation leads to lipolysis, breakdown of triglycerides. |
Agonist | medication or other substance that binds with a specific medication receptor and causes a physiological response. |
Antagonist | medication or other substance that blocks a physiological response that blocks the action of another medication or substance. |
Adrenergic | related to the SNS, receptors specific to norepinephrine and epinephrine-like substances |
Pressor | Base substance capable of raising blood pressure, reflex is a nerve causing constriction of arterioles increasing blood pressure. |
Sympathomimetic | medication or other substance that causes effects such as those of the SNS (adrenergic) |
Sympatholytic | medications blocking beta adrenergic receptors and slow heart rate |
Parasympathomimetics | medications stimulating the parasympathetic nerve system |
Parasympatholytic | Medications that inhibit the parasympathetic nerve system |
Chronotrophy | change the heart rate by affecting the nerves controlling the heart, or by changing the rhythm produced by the sinoatrial node. Positive chronotropes increase heart rate; negative chronotropes decrease heart rate. |
Dromotrophy | affects the conduction speed in the AV node, and subsequently the rate of electrical impulses in the heart |
Inotrophy | alters the force or energy of muscular contractions. |