The pancreas is an essential organ for life, as it secretes juices and hormones vital for the digestion of food. A review of its parts and associated diseases.
The pancreas is an organ that is part of the digestive system and at the same time of the endocrine, since it has an important secretory function. It is also considered a mixed gland, as it is composed of two types of tissue, one endocrine and one exocrine.
This organ is of vital importance in the physiology of human beings but, unfortunately, pancreatic cancer is on the rise, either by a greater refinement to detect it or by an increasingly widespread unhealthy lifestyle: smoking, overweight and diabetes promote the appearance of pancreatic cancer, according to the American Cancer Society.
Thus, it is estimated that only in the United States almost 57,000 adults are diagnosed with pancreatic cancer per year, that is, 3% of all cancerous tumors correspond to this disease. In the following lines we will take a tour of the pancreas: physiology, functions and diseases that affect it, among many other things. If you want to know more about this essential organ, continue reading.
- We recommend you read: “The 8 parts of the human vesicle (and their functions)”
What is the pancreas?
The pancreas is a small organ, about 15 centimeters long and weighing 100 grams on average, located in the abdominal cavity, immediately behind the stomach, between the spleen and the duodenum. Here are some data that characterize this body in a general way:
- Macroscopically, this organ is pale (yellowish) in appearance and lobed.
- Its weight is constituted by water in 71%, proteins in 13% and fats in a variable proportion (3-20%).
- This organ has both an exocrine and endocrine function, that is, it secretes both the interstitium of the tissues and into ducts.
- Anatomically, the pancreas is divided into 4 main sections: head, neck, body and tail.
Parts of the pancreas
Once we have drawn a general concept of the pancreas with the most important data about it, we are prepared to dissect its anatomy in a cursory way. Let’s do it:
- Head: it is the thickest part, located on the right, behind the liver and partially surrounding the duodenum.
- Neck: the area that joins the body and head. It is located below the duodenum.
- Body: the central part of the pancreas. It has a 3-sided prismatic geometric shape.
- Tail: extension of the body that extends to the spleen. It is the only part of the intraperitoneal pancreas, that is, it is located within the peritoneum (abdominal membrane).
It should also be noted that the pancreas has a series of ducts, such as the Wirsung duct. This is the main duct, which arises from the tail of the pancreas, and crosses the body, neck and head of this gland to flow into the duodenum, next to the common bile duct of the gallbladder. It is by this path that the organ secretes pancreatic juice, which favors secretion.
Function of the pancreas
The physiology of the pancreas naturally leads us to describe its functions. As we have already said in previous lines, we are facing an organ of glandular nature, since its function is secretion, both endocrine and exocrine. We tell you each of them in detail below.
1. Exocrine function
First, it should be noted that tissues with endocrine and exocrine function are grouped together forming macroscopically visible lobes, which are separated from each other by connective tissue septa containing blood vessels, lymphatic vessels and nerve endings.
85% of the pancreatic volume is composed of the main portion of the tissue, exocrine in nature. The secretory cells of this area are responsible for producing enzymes (mainly lipase and amylase), which are essential to chemically break down the fats and proteins ingested in small portions that can be absorbed by the small intestine (remember that this organ pours into the duodenum). The dominant cell body in this tissue is the acinar cells.
The glandular function of this tissue is said to be exocrine because it pours its contents into a duct (in this case into the Wirsung duct), which flows elsewhere (the duodenum of the small intestine) to facilitate digestion.
2. Endocrine function
Of the remaining 15% of tissue, 10% or more corresponds to the extracellular matrix and blood vessels. Therefore, weonly have approximately 2% of tissue with endocrine function, but it is no less important. The basic histological unit of this section is the pancreatic islets, which consist of clusters of hormone-secreting cells. Next, we review each of those present:
- Alpha cells: synthesize and release glucagon. Its main function is to stimulate the production of glucose, thus increasing blood glucose.
- Beta cells: synthesize and release insulin. This hormone is essential, as it participates in the regulation of blood sugar levels.
- Delta cells: produce somatostatin, a hormone that inhibits the synthesis of insulin and glucagon. In other words, it regulates the activity of alpha and beta cells.
- Epsilon cells: produce ghrelin, a hormone that induces the feeling of hunger in the individual.
- PP cells: produce substances that regulate exocrine secretion from the pancreas.
All these cells are considered endocrine because they lack ducts, that is, they discharge hormones directly into the interstitium and these diffuse into the bloodstream. Its function is very different from that of exocrine cells because, as you may have seen, they are characterized by hormonal production and not by synthesizing pancreatic juices.
About pancreatic juice
Speaking of juices and excreted substances, we can not leave in the inkwell the characteristics of pancreatic juice, produced by exocrine tissue. We are facing a colorless liquid, of aqueous nature, with a variable density according to the concentration of proteins stored in it. Pancreatic juice is alkaline in nature and has two types of secretions: enzymatic and electrolytic.
The enzymatic secretion responds to the enzymes mentioned above (amylase and lipase), responsible for the hydrolysis of nutrients in food. On the other hand, the electrolytic section acts as a “vehicle” of the enzyme and provides an alkaline medium, necessary for the proper functioning of enzymes. Both elements, in conjunction and with the help of bile produced in the gallbladder, work to perform digestion at the level of the small intestine.
As a final curious fact regarding this liquid, it should be noted that, under normal conditions, the total daily volume produced of pancreatic juice ranges between 1 and 4 liters. When this organ is stimulated properly, 5 milliliters of it can be generated per minute, a not inconsiderable figure.
Pancreatic cancer: a serious pathology
Once we have described the parts of the pancreas, its functions and the characteristics of pancreatic juice, we can only talk about the uncomfortable topic that we have advanced in the first lines: pancreatic cancer. We believe the data speaks for itself, so here are a number of figures from the American Society of Clinical Oncology (ASCO) and other professional sources:
- Nearly 57,000 patients with pancreatic cancer are diagnosed annually in the United States. This corresponds to 3% of all cancers.
- Annually, almost 47,000 people die with this pathology. Only 9% of them survive 5 years after diagnosis.
- Pancreatic cancer is the ninth most common cancer in women and the tenth in men.
- 7.5 and 4.9 out of every 100,000 men and women will face pancreatic cancer at some point in their lives.
Although we are facing a relatively rare disease, the media inform us thatits incidence has increased steadily since the fifties, rising hand in hand with it the mortality rate. This is probably because, as we have said, certain habits of life can lead to the appearance of pancreatic cancer.
The most important of them all is smoking. It is estimated that 25% of pancreatic cancers are a direct cause of cigarette smoking. Secondly, we have undoubtedly obesity, because an obese person is approximately 20% more likely to suffer from pancreatic cancer throughout his life. While the appearance of a malignant tumor is in many cases a lottery, these statistics underscore that we are clearly to some extent masters of our destiny.
Summary
As you may have seen, the characteristics and functions of the pancreas are almost unfathomable. The exocrine function of it is relatively easy to explain, since pancreatic juice plays a specific function, but the endocrine part produces many hormones whose function extends far beyond the digestive tract.
The pancreas is a multifaceted organ essential for life, and proof of this is that the survival rate of people with malignant tumors in it is very low. Remember that pancreatic cancer is an increasingly current threat in society but, luckily, you can avoid it with a proper lifestyle.
To the classic question “what do you do?” I always answer “basically I am a psychologist”. In fact, my academic training has revolved around the psychology of development, education and community, a field of study influenced my volunteer activities, as well as my first work experiences in personal services.