- Blood sugar regulation
Blood sugar regulation is the process by which the levels of
blood sugar , primarilyglucose , are maintained by the body.Mechanisms of blood sugar regulation
Blood sugar levels are regulated by
negative feedback in order to keep the body inhomeostasis . The levels ofglucose in the blood are monitored by the cells in thepancreas 'sIslets of Langerhans . If the blood glucose level falls to dangerous levels (as in very heavy exercise or lack of food for extended periods), theAlpha cells of the pancreas releaseglucagon , ahormone whose effects on liver cells act to increase blood glucose levels. They convertglycogen storage into glucose (this process is calledglycogenolysis ). The glucose is released into the bloodstream, increasing blood sugar levels.There are also several other causes for an increase in blood sugar levels. Among them are the 'stress' hormones such as adrenaline, several of the steroids, infections, trauma, and of course, the ingestion of food.
When levels of blood sugar rise, whether as a result of
glycogen conversion, or from digestion of a meal, a different hormone is released frombeta cells found in theIslets of Langerhans in the pancreas. This hormone,insulin , causes the liver to convert more glucose into glycogen (this process is calledglycogenesis ), and to force about 2/3 of body cells (primarilymuscle and fat tissue cells) to take up glucose from the blood, thus decreasing blood sugar levels. Insulin also provides signals to several other body systems, and is the chief regulatory metabolic control in humans.Diabetes mellitus type 1 is caused by insufficient or non-existent production of insulin, while type 2 is primarily due to a decreased response to insulin in the tissues of the body (insulin resistance ). Both types of diabetes, if untreated, result in too much glucose remaining in the blood (hyperglycemia ) and many of the same complications. Also, too much insulin and/or exercise without enough corresponding food intake in diabetics can result in low blood sugar (hypoglycemia ).Hormones that influence blood glucose level
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