Insulin is produced by beta cells of pancreas. It is called anabolic because it promotes synthesis - synthesis of glycogen, protein and triglycerides.

Regulation of insulin secretion in the body :

Glucose - After ingestion of carbohydrate rich diet, there will be increased levels of glucose in the blood. Beta cells sense this increase and releases insulin.

Aminoacids - Ingestion of protein leads to increase in amino acids in the blood. This is also a stimulus for insulin release.

Hormones produced in the intestines - like secretin. They are released in to blood when we eat food. And these rise the levels of insulin well before the actual glucose increased in the blood.

All above factors increase insulin secretion after food, where as in fasting the insulin secretion is inhibited. We need fuel in fasting states, so epinephrine (a stress induced hormone) inhibits insulin secretion and mobilizes glucose from liver and fatty acids from fat stores. These glucose and fatty acids are used as fuel in starving state.

How insulin acts in the body :

* In muscle and fat, insulin increases glucose uptake by increasing the number of transporters in the cell membrane.

* In liver, insulin decreases the breakdown of glycogen (glucose storage form) to glucose.

* In liver , insulin inhibits glucose synthesis.

* In fat stores, insulin inhibits release of fatty acids in to the blood.

* Insulin increases uptake of amino acids by cells leading to protein synthesis.

Types of insulin preparations :

Rapid-acting insulin - Action will be with in 20 minutes. It is convenient for taking before meals and don’t have to wait 60 minutes as with regular insulin. But patient is instructed to eat carbohydrates first.

Short-acting insulin - Effect occurs with in 30 minutes after subcutaneous injection and lasts for around 6 hours. It is generally used after hyperglycemic episodes and emergencies, after insulin changing needs like after surgeries.

Intermediate-acting insulin - Example is Lente insulin. Its action starts within 2 hours and extended up to 18 - 24 hours. It needs two doses per day for this reason. It is used for regular daily maintenance of blood sugar.

Long-acting insulin - These actions prolonged more than 24 hours. Daily dose is used in two divided doses.

Most important thing to follow when using insulins is careful monitoring of blood glucose at home, recording it in a dairy. Follow your doctors instructions carefully, when to take and how much to take. Any deviation from your original healthy state should be intimated to your doctor for further checking.

Tags: diabetes, insulin, diabetic