Related Experiment Video
Updated: Feb 13, 2026
07:00
Mechanisms Underlying Gut Hormone Secretion Using the Isolated Perfused Rat Small Intestine
Published on: February 26, 2019
10.1K
Physostigmine-induced salivary secretion in the rat
1Department of Physiology and Biophysics, Georgetown University Medical Center, Washington, DC 20007.
Archives of Oral Biology
|January 1, 1990
Summary
Physostigmine, a cholinesterase inhibitor, stimulates rat salivary secretion via cholinergic and alpha-adrenergic receptors, affecting parotid and submandibular glands but not sublingual glands.
Area of Science:
- Pharmacology
- Physiology
- Salivary Gland Biology
Background:
- Cholinesterase inhibitors are drugs that increase acetylcholine levels.
- Salivary gland secretion is regulated by the autonomic nervous system.
- Understanding drug effects on salivary glands is crucial for therapeutic applications.
Purpose of the Study:
- To investigate the effects of physostigmine on salivary secretion and composition in rats.
- To determine the specific salivary glands affected by physostigmine.
- To elucidate the receptor mechanisms mediating physostigmine-induced salivation.
Main Methods:
- Administration of varying doses of physostigmine to rats.
- Collection and analysis of saliva from parotid, submandibular, and sublingual glands.
- Measurement of ion (Ca, Na, K) and protein concentrations, and amylase activity.
- Pharmacological blockade studies using atropine, reserpine, and phentolamine.
- Assessment of morphological changes in salivary glands via microscopy.
Main Results:
- Physostigmine induced significant salivary flow from parotid and submandibular glands at higher doses, with no sublingual secretion.
- Ion and protein concentrations in physostigmine-induced saliva showed distinct patterns compared to other stimuli.
- Amylase activity was notably higher in physostigmine-evoked parotid saliva.
- Secretion was blocked by cholinergic antagonists and partially by alpha-adrenergic antagonists, independent of sympathectomy.
- Morphological changes included decreased acinar secretory granules and vacuole formation in parotid glands.
Conclusions:
- Physostigmine primarily stimulates salivary secretion through direct action on cholinergic and alpha-adrenergic receptors.
- The study highlights differential effects on major salivary glands and specific ion/protein profiles.
- These findings contribute to understanding the complex regulation of salivary secretion by pharmacological agents.
Related Concept Videos
01:28Reabsorption and Secretion in the PCT
3.7K
The Proximal Convoluted Tubule, or PCT, plays a pivotal role in the body's filtration system. They are primarily responsible for reabsorbing solutes and water from the filtered fluid produced by the glomeruli. Most of the filtered water, ions, and organic solutes such as glucose and amino acids are reabsorbed by the PCT.
Transport mechanisms involving sodium ions (Na+) contribute significantly to solute reabsorption. These mechanisms include symport and antiport processes.
A key example is the...
Transport mechanisms involving sodium ions (Na+) contribute significantly to solute reabsorption. These mechanisms include symport and antiport processes.
A key example is the...
3.7K
01:23Salivary Glands and Saliva
2.6K
The salivary glands, of which there are three pairs known as the parotid, submandibular, and sublingual glands, play a crucial role in maintaining oral health and initiating the digestive process. Positioned near the ears, beneath the masseter muscle, the parotid glands secrete saliva into the oral cavity through the parotid duct of Stensen. Meanwhile, the submandibular glands, located on the floor of the mouth, secrete saliva through channels named submandibular ducts. The sublingual glands,...
2.6K
01:19Regulation of Hormone Secretion
7.0K
Regulation of hormone secretion is a finely tuned orchestration driven by various types of stimuli, encompassing neural, humoral, and hormonal signals. Environmental cues instigate neural stimuli, where action potentials traverse nerve fibers to reach their designated targets. An illustrative scenario is the body's response to stress, wherein the sympathetic nervous system releases epinephrine from the adrenal glands, inducing the well-known 'fight or flight' reaction.
Humoral...
Humoral...
7.0K
01:25Hormones Secreted by the Stomach
2.8K
Enteroendocrine cells, accounting for only 1% of stomach epithelial cells, play a significant role in digestion and are classified by their digestive hormone secretions.
Each of these hormones secreted by different enteroendocrine cells plays a unique role in digestion. Here are a few examples:
Each of these hormones secreted by different enteroendocrine cells plays a unique role in digestion. Here are a few examples:
2.8K
01:26Pancreatic Juice and Secretion
3.1K
Pancreatic juice is a clear fluid produced by the pancreas, containing water, salts, sodium bicarbonate, and enzymes vital for digestion in the small intestine. It helps break down large molecules, facilitating nutrient absorption.
When acidic chyme from the stomach enters the duodenum, it triggers the release of secretin, a hormone that prompts pancreatic juice secretion. After a fatty meal, cholecystokinin, another hormone, stimulates gallbladder contraction and enhances enzyme-rich...
When acidic chyme from the stomach enters the duodenum, it triggers the release of secretin, a hormone that prompts pancreatic juice secretion. After a fatty meal, cholecystokinin, another hormone, stimulates gallbladder contraction and enhances enzyme-rich...
3.1K
01:28Tubular Reabsorption and Secretion
6.9K
Tubular secretion and reabsorption are two critical processes in the nephron tubule of the kidneys. When the fluid filtered from the glomerulus enters the proximal convoluted tubule, it is referred to as filtrate, and its composition changes due to tubular reabsorption and secretion.
Tubular reabsorption is a selective process that starts when the filtrate enters the proximal tubules. It involves substances traveling through the transcellular route (through the tubule cell and peritubular...
Tubular reabsorption is a selective process that starts when the filtrate enters the proximal tubules. It involves substances traveling through the transcellular route (through the tubule cell and peritubular...
6.9K