Related Experiment Video
Updated: Jul 29, 2026
11:47
Bronchoalveolar Lavage (BAL) for Research; Obtaining Adequate Sample Yield
Published on: March 24, 2014
How does lobeline injected intravenously produce a cough?
Hans Raj1, G S Bakshi, R R Tiwari
1Department of Electrophysiology, Vidyasagar Institute of Mental Health and Neurosciences, New Delhi 110065, India.
Respiratory Physiology & Neurobiology
|January 18, 2005
Summary
Lobeline-induced cough is a true reflex, not a voluntary action. Studies on comatose and anesthetized subjects confirm this reflex mechanism, unaffected by conscious perception.
Area of Science:
- Respiratory Physiology
- Neuroscience
Background:
- The nature of lobeline-induced cough (reflex vs. voluntary) requires investigation.
- Understanding the cough reflex pathway is crucial for respiratory research.
Purpose of the Study:
- To determine if lobeline-induced cough is a reflex or voluntary effort.
- To elucidate the physiological basis of lobeline's effect on respiration.
Main Methods:
- Systematic study of cough response to lobeline in comatose and anesthetized subjects.
- Dose-response relationship analysis and latency/duration measurements.
- Comparison of cough responses in conscious, anesthetized, and comatose individuals.
Main Results:
- Lobeline consistently induced cough in comatose and anesthetized subjects, indicating a reflex.
- A dose-response relationship was observed, with higher doses increasing cough intensity and duration.
- No significant difference in dose, latency, or duration was found between pre-anesthesia and post-anesthesia states.
Conclusions:
- Lobeline-induced cough is unequivocally a reflex response.
- Conscious perception may modulate the magnitude of the cough response.
- The cough likely originates from juxtapulmonary capillary receptors.
Related Concept Videos
01:25Adrenergic Agonists: Indirect-Acting Agents
Indirect-acting adrenergic agonists potentiate the effects of endogenous catecholamines through different mechanisms without directly binding to adrenoceptors.
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral bioavailability, and...
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral bioavailability, and...
01:19Depolarizing Blockers: Pharmocokinetics
Depolarizing blockers are administered through intravenous injection. Succinylcholine is the most common choice of depolarizing blockers in emergency clinical practices. Although they have a rapid onset, they readily diffuse away from the motor end plate into the extracellular fluid. They are metabolized by enzymes such as liver butyrylcholinesterase and plasma pseudocholinesterases. This produces a short duration of action, typically 5-10 minutes long, unlike nondepolarizing blockers, which...
01:17Drugs Used in Lower Respiratory Disorders: Overview
Lower respiratory tract disorders present challenges that often require skilled and nuanced approaches for effective management. Common ailments, such as asthma and chronic obstructive pulmonary disease (COPD), have prompted the development of intricate treatment strategies involving bronchodilators and anti-inflammatory drugs, each tailored to ease breathing and revitalize the lungs.
Bronchodilators, the first step of respiration enhancement, come in various forms, each with its own mechanism...
Bronchodilators, the first step of respiration enhancement, come in various forms, each with its own mechanism...
01:23Upper Respiratory Drugs: Antitussives, Expectorants, and Mucolytics
Respiratory symptoms, such as congestion and cough, commonly accompany respiratory tract conditions. Various medications, such as antitussives, expectorants, and mucolytics, play crucial roles in providing relief.
Antitussives include codeine, dextromethorphan (Robitussin), and benzonatate (Tessalon). Codeine and dextromethorphan exert their effects centrally by suppressing the cough reflex center in the medulla. Benzonatate operates peripherally within the respiratory tract by anesthetizing...
Antitussives include codeine, dextromethorphan (Robitussin), and benzonatate (Tessalon). Codeine and dextromethorphan exert their effects centrally by suppressing the cough reflex center in the medulla. Benzonatate operates peripherally within the respiratory tract by anesthetizing...
01:23Inhaled Medications
Inhaled medications are crucial for managing chronic obstructive pulmonary disease (COPD) and asthma. They are essential for effective treatment and control, ensuring optimal respiratory health and well-being. Inhaled medication delivers drugs directly to the lungs, providing a rapid onset of action and reducing systemic side effects compared to oral or injectable medications. Three primary types of inhalation devices are used to administer these medications: nebulizers, metered-dose inhalers...
01:29Drug Delivery: Parenteral Route
The parenteral route is a critical method of drug administration. It delivers compounds directly into the systemic circulation and bypasses the gastrointestinal tract. This approach is particularly advantageous for drugs that exhibit poor absorption or instability when administered orally.
There are three primary parenteral routes: intravenous (IV), intramuscular (IM), and subcutaneous (SC). The IV route introduces the drug directly into the bloodstream, ensuring immediate action. The IM route...
There are three primary parenteral routes: intravenous (IV), intramuscular (IM), and subcutaneous (SC). The IV route introduces the drug directly into the bloodstream, ensuring immediate action. The IM route...