The choleretic effect of iodipamide.
The Journal of Clinical Investigation
|March 1, 1975
Summary
Iodipamide, a radiographic contrast agent, significantly enhances bile flow by stimulating the bile canaliculi. This potent choleretic effect, observed in dogs, exceeds that of taurocholate, indicating efficient water transport into bile.
Area of Science:
- Hepatology
- Gastroenterology
- Pharmacology
Background:
- Organic anions are excreted by the liver into bile, increasing bile flow.
- Iodipamide, a radiographic contrast material, is a known potent choleretic agent.
Purpose of the Study:
- To determine if iodipamide-induced bile flow increase is canalicular or ductular.
- To quantify choleresis from iodipamide and taurocholate excretion.
- To correlate in vivo findings with in vitro osmotic activity.
Main Methods:
- Experiments in unanesthetized dogs.
- Measurement of plasma erythritol clearance.
- In vitro determination of osmotic activities of iodipamide and taurocholate in saline and bile.
Main Results:
- Plasma erythritol clearance increased linearly with iodipamide excretion, indicating canalicular stimulation.
- Iodipamide's choleretic potency (22 ml/mmol) is ~3x that of taurocholate (7.8 ml/mmol).
- Iodipamide's osmotic activity in bile (1.5 mosmol/mmol) is ~2x that of taurocholate (0.8 mosmol/mmol).
Conclusions:
- Iodipamide stimulates bile flow primarily through the bile canaliculi.
- Iodipamide is a more potent choleretic agent than taurocholate.
- Iodipamide appears to transport more water per unit of effective osmotic solute secreted into bile canaliculi compared to taurocholate.
Related Concept Videos
01:18Indirect-Acting Cholinergic Agonists: Mechanism of Action
Indirect-acting cholinergic agonists work by interacting with an enzyme called acetylcholinesterase (AChE) in the synaptic cleft. They can be reversible or irreversible inhibitors and have different effects on the enzyme.
Reversible inhibitors like edrophonium bind to a specific part of the enzyme called the anionic catalytic site. They form noncovalent bonds, which means they are not strongly attached to the enzyme. This creates a temporary and less stable enzyme–inhibitor complex, leading to...
Reversible inhibitors like edrophonium bind to a specific part of the enzyme called the anionic catalytic site. They form noncovalent bonds, which means they are not strongly attached to the enzyme. This creates a temporary and less stable enzyme–inhibitor complex, leading to...
01:30Indirect-Acting Cholinergic Agonists: Pharmacological Actions
Indirect-acting cholinergic agonists, also known as anticholinesterases, exert their pharmacological effects by enhancing cholinergic transmission in various body parts, including the neuromuscular junction, autonomic cholinergic synapses, and the brain.
At the neuromuscular junction, these agents work by inhibiting the breakdown of acetylcholine, allowing it to remain bound to the receptor and bind to nearby receptors. This process leads to repetitive firing of the endplate, causing muscle...
At the neuromuscular junction, these agents work by inhibiting the breakdown of acetylcholine, allowing it to remain bound to the receptor and bind to nearby receptors. This process leads to repetitive firing of the endplate, causing muscle...
01:26Anticholinesterase Agents: Poisoning and Treatment
Anticholinesterases, also known as cholinesterase inhibitors, work by blocking the breakdown of acetylcholine, leading to its accumulation in the synaptic cleft. This accumulation indirectly enhances both muscarinic and nicotinic actions. These agents are classified as reversible or irreversible based on their mechanism of action.
Irreversible agents form a strong bond with the cholinesterase enzyme, making it inactive. The breakdown of the phosphorylated enzyme is slower than the...
Irreversible agents form a strong bond with the cholinesterase enzyme, making it inactive. The breakdown of the phosphorylated enzyme is slower than the...
01:26Cholinergic Antagonists: Therapeutic Uses
Antimuscarinic drugs have various therapeutic applications by inhibiting parasympathetic stimulation in different systems. Here are the key therapeutic uses of antimuscarinics:
Respiratory Tract: Ipratropium, aclidinium, and tiotropium treat asthma, chronic bronchitis, and chronic obstructive pulmonary disease (COPD). They protect against bronchoconstriction caused by irritants like cigarette smoke, sulfur dioxide, and ozone. They also help reduce nasopharyngeal secretions in common...
Respiratory Tract: Ipratropium, aclidinium, and tiotropium treat asthma, chronic bronchitis, and chronic obstructive pulmonary disease (COPD). They protect against bronchoconstriction caused by irritants like cigarette smoke, sulfur dioxide, and ozone. They also help reduce nasopharyngeal secretions in common...
01:21Skeletal Muscle Relaxants: Adverse Effects
Skeletal muscle relaxants are widely used for muscle paralysis and relieving pain following any muscle injury or stiffness. However, depending on the drug type, they can have adverse effects that range from mild to severe. Usually, nondepolarizing neuromuscular blockers have minimal side effects. For example, drugs like d-tubocurarine, cisatracurium, and rocuronium cause hypotension, whereas drugs like baclofen, when stopped abruptly, can lead to the recurrence of spastic conditions.
Unlike...
Unlike...
01:17Drugs for Treatment of Diarrhea-Predominant IBS
Diarrhea-predominant irritable bowel syndrome (IBS-D) is a subtype of IBS characterized primarily by frequent, loose, or watery stools, abdominal pain, and abdominal discomfort. Therapeutic approaches to managing IBS-D include dietary changes, stress management techniques, and pharmaceutical interventions.
Two specific drugs used in the treatment are alosetron (Lotronex) and eluxadoline (Viberzi). Alosetron, a 5-HT3 antagonist, works by slowing the movement of stools in the gut, reducing bowel...
Two specific drugs used in the treatment are alosetron (Lotronex) and eluxadoline (Viberzi). Alosetron, a 5-HT3 antagonist, works by slowing the movement of stools in the gut, reducing bowel...