Related Experiment Video
Updated: Aug 10, 2026
08:32
Disrupting Reconsolidation of Fear Memory in Humans by a Noradrenergic β-Blocker
Published on: December 18, 2014
Epinephrine and recovery from punishment
The Journal of Pharmacology and Experimental Therapeutics
|August 1, 1977
Summary
Adrenal demedullated rats recovered faster from suppressed activity after footshock. Epinephrine administration hindered this recovery, suggesting its role in adapting to aversive experiences.
Area of Science:
- Neuroscience
- Behavioral Science
- Endocrinology
Background:
- Adrenal medulla plays a role in stress response.
- Epinephrine is a key hormone released by the adrenal medulla.
Purpose of the Study:
- To investigate the role of epinephrine in behavioral adaptation to aversive experiences.
- To determine if adrenal demedullation affects recovery from suppressed motor activity.
Main Methods:
- Rats underwent adrenal demedullation or sham surgery.
- Motor activity was suppressed using footshocks.
- Recovery of spontaneous activity was measured in subsequent sessions.
- Epinephrine and various drugs were administered to assess their effects on recovery.
Main Results:
- Adrenal demedullated rats showed faster recovery of motor activity post-punishment compared to sham-operated rats.
- Epinephrine administration to demedullated rats abolished the accelerated recovery.
- In intact rats, dl-propranolol and an inhibitor of phenylethanolamine N-methyltransferase mimicked the effects of demedullation.
Conclusions:
- Epinephrine is crucial in modulating behavioral adaptation to aversive stimuli.
- The adrenal medulla's epinephrine output influences the rate of recovery from stress-induced behavioral suppression.
Related Concept Videos
01:27Adrenergic Neurons: Neurotransmission
Postganglionic sympathetic fibers (except those supplying the sweat glands) releasing noradrenaline or norepinephrine are called noradrenergic or adrenergic neurons. Noradrenaline, dopamine, adrenaline, or epinephrine are collectively called "catecholamines" as they contain a catechol moiety and an amine side chain. The five stages of neurotransmitter release involve their synthesis, storage, release, reuptake and metabolism.
Synthesis: Catecholamine synthesis requires tyrosine, which is taken...
Synthesis: Catecholamine synthesis requires tyrosine, which is taken...
01:28Adrenergic Agonists: Mixed-Action Agents
Mixed-action adrenergic agonists, like ephedrine and pseudoephedrine, directly and indirectly affect adrenergic receptors. These agents stimulate adrenoceptors and indirectly release stored neurotransmitters, amplifying the adrenergic response.
Ephedrine and pseudoephedrine lack a catecholamine group, making them less susceptible to degradation by metabolic enzymes. They have increased oral bioavailability and lipophilicity, resulting in a longer duration of action. Their response is reduced by...
Ephedrine and pseudoephedrine lack a catecholamine group, making them less susceptible to degradation by metabolic enzymes. They have increased oral bioavailability and lipophilicity, resulting in a longer duration of action. Their response is reduced by...
01:18Adrenergic Agonists: Therapeutic Classification
Adrenergic agonists can be classified based on their therapeutic uses and mechanisms of action. They serve various purposes in clinical applications.
Vasopressor or pressor agents: They increase blood pressure and function as cardiac stimulants. Examples include endogenous catecholamines (norepinephrine and dopamine) and synthetic agents (phenylephrine).
Bronchodilators: β2-agonists can relax bronchial muscles and widen airways. They are commonly used for treating obstructive pulmonary...
Vasopressor or pressor agents: They increase blood pressure and function as cardiac stimulants. Examples include endogenous catecholamines (norepinephrine and dopamine) and synthetic agents (phenylephrine).
Bronchodilators: β2-agonists can relax bronchial muscles and widen airways. They are commonly used for treating obstructive pulmonary...
01:30Adrenergic Agonists: Therapeutic Uses
Adrenergic agonists have diverse therapeutic uses across various medical conditions and emergencies.
Emergency and Intensive Care Unit (ICU) applications: Pressor agents increase blood pressure, heart rate, and contractility in shock and organ failure situations. Dopamine can induce vasodilation and stimulate adrenoceptors. Endogenous catecholamines are effective in treating cardiogenic shock. α2-agonists like clonidine can reverse anesthesia-induced hypertension.
Allergies and anaphylaxis:...
Emergency and Intensive Care Unit (ICU) applications: Pressor agents increase blood pressure, heart rate, and contractility in shock and organ failure situations. Dopamine can induce vasodilation and stimulate adrenoceptors. Endogenous catecholamines are effective in treating cardiogenic shock. α2-agonists like clonidine can reverse anesthesia-induced hypertension.
Allergies and anaphylaxis:...
01:25Cardiopulmonary Resuscitation IV: Pharmacological Management
Pharmacologic intervention is crucial in treating cardiac arrest patients during ACLS or Advanced Cardiovascular Life Support. The ACLS algorithms guide the administration of specific drugs based on the patient's cardiac arrest rhythm, which includes pulseless ventricular tachycardia (VT), ventricular fibrillation (VF), asystole, and pulseless electrical activity (PEA).EpinephrineIndication: Epinephrine is the first-line drug for all cardiac arrest rhythms.Mechanism of Action: Epinephrine...
01:24Physiological Foundation of Stress
Stress triggers a coordinated physiological response involving the sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenal (HPA) axis. This dual activation ensures that the body is prepared for both immediate and prolonged stress management. The process begins with the perception of a stressor. This initial phase activates the SNS, leading to the rapid release of adrenaline (epinephrine) from the adrenal glands.
Role of the Sympathetic Nervous System
Adrenaline triggers the...
Role of the Sympathetic Nervous System
Adrenaline triggers the...