Question

In humans, sphincter of oddi is associated with the opening of
A. Hepatopancreatic ampulla
B. Pyloric stomach
C. Oesophagus
D. Common hepatic duct

Answer 1

Hint: The sphincter of Oddi (Glisson's sphincter), could be a muscular valve that in some animals, including humans, controls the flow of digestive juices (bile and pancreatic juice) through the ampulla of Vater into the second a part of the duodenum.

Complete answer:
The sphincter of Oddi (SO) is a smooth muscle valve located within the second portion of the duodenum. It serves to manage the flow of hepatic and pancreatic substances into the tiny intestines. Although its function seems simple, it represents a good example of how smooth muscle will be under the regulation by hormones and other signals. The SO serves many purposes in medicine and is usually traversed in procedures like endoscopic retrograde cholangiopancreatography (ERCP). This sphincter might also become dysfunctional from time to time requiring either medical or surgical intervention.
Functions:
> To stop reflux of duodenal contents thereby preventing the buildup of sludge and material within the bile ducts and thus helps to cut back the danger of cholangitis.
> Regulate the flow of bile and pancreatic secretions.
> Allow retrograde filling of the gallbladder.
> The sphincter of Oddi originates from the mesenchyme surrounding the pre-ampullary portion of the bile and pancreatic ducts. Initially, it begins as a transverse slit within the circular smooth muscle at the junction between the duodenal wall and also the bile and pancreatic ducts. The sequence of SO differentiation is:
> Week 10: Sphincter of Oddi begins differentiation.
> Week 12: The bile and pancreatic ducts emerge through the transverse slit of the concentric smooth muscle of the duodenum.
> Week 16: The muscularis propria extends outside the fenestra to the upper end of the ampulla.
> Week 28: The muscularis propria is differentiated almost to the distal end of the ampulla.

Therefore, the correct answer is a. hepatopancreatic ampulla.

Note: The SO is regulated by several gastrointestinal hormones, and its basal pressure and phasic contractions will be elevated or decreased significantly by exogenous drugs. Its role in gallstone formation is maybe negligible, but severing the SO allows one to extract CBD stones with an endoscope. Abnormal function of the SO can cause biliary-like pain. Endoscopic or surgical sphincterotomy can cure these patients of their pain. The SO may play a big role within the development of pancreatitis in certain patients, either due to the connection of the CBD orifice to the duct orifice created by the SO or thanks to the response of the SO to exogenous agents, like alcohol.