Related Experiment Video
Updated: Jul 16, 2026

In vitro Measurements of Tracheal Constriction Using Mice
Published on: June 25, 2012
Comparison of calcium channel blocking agents and an anticholinergic agent on oesophageal function
M Allen1, M Mellow, M G Robinson
1HCA Presbyterian Hospital, Department of Clinical Physiology, Oklahoma City, Oklahoma 73104.
Abstract:
The effects of oral doses of three calcium blockers and an anticholinergic drug on oesophageal function were compared. Nifedipine (20 mg) and hyoscyamine (0.25 mg) significantly reduced lower oesophageal sphincter (LES) pressure and oesophageal contractile pressure. Verapamil (120 mg) and diltiazem (60 mg) had no significant effect on any of the oesophageal variables measured. Oesophageal transit time and oesophageal contractile duration were not affected significantly by any of the agents. Only hyoscyamine significantly prolonged acid clearance time. The combination of nifedipine and hyoscyamine was no more effective in decreasing LES pressure or oesophageal contractile pressure than either agent alone. Either nifedipine or hyoscyamine would appear to be potentially effective for the treatment of oesophago-spastic and other hypertensive motor disorders, but hyoscyamine may lead to prolongation of acid clearance from the oesophagus.
Related Concept Videos
Direct-Acting Cholinergic Agonists: Therapeutic Uses
Indirect-Acting Cholinergic Agonists: Pharmacological Actions
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...
Cholinergic Antagonists: Pharmacological Actions
Gastrointestinal Effects: Antimuscarinics reduce gut contractions, increase gastric emptying, and slow intestinal transit. They partly inhibit gastric acid secretion...
Cholinergic Antagonists: Therapeutic Uses
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...
Antihypertensive Drugs: Action of Calcium Channel Blockers
Antianginal Drugs: Calcium Channel Blockers and Ranolazine
CCBs, a diverse class that includes dihydropyridines (nifedipine) and diphenylalkylamines (verapamil and diltiazem), exert their effect by blocking calcium channels in cardiac and smooth muscle cells. This...

