Insulin: Metabolic Effects and Counterregulatory Hormones

00:00 Insulin counter-regulatory hormones.

00:05 Counter-regulatory hormones now that's a mouthful isn't it.

00:09 Think about a counter-regulatory hormone as being the opposite of effect of what happens with insulin.

00:16 Though insulin does one thing if the opposite thing happens that's kind a regulatory.

00:22 So catecholamine is one of those items that can cause counter-regulatory response with insulin.

00:29 What are your catecholamines? Epinephrine, norepinephrine.

00:33 This causes glycogenolysis.

00:35 So this is the breakdown of glycogen which is the opposite of what insulin does.

00:39 Insulin causes gluconeogenesis which is making new glycogen.

00:41 Catecholamines also cause the lipolysis.

00:47 So lipolysis and increase in plasma lactate these are the opposite of what insulin would do.

00:56 If we look at our glucocorticoids -- and remember one is cortisol.

01:02 Cortisol causes effects in which you get breakdown of protein in muscle, in the liver cell, it mobilizes free fatty acids from adipose tissue.

01:14 These are all opposite effects.

01:17 They are catabolic effects while insulin does anabolic effects.

01:24 The other thing that glucocorticoids do is cause gluconeogenesis rather than glycolysis.

01:29 Growth hormones also causes glypolysis, gluconeogenesis, and it decreases glucose uptake by muscle cells or myocytes.

01:42 Those again are all things that will go in opposition to what insulin is trying to do.

01:49 So when you think about, you have to think about what is the blood glucose level, what are all those things that are stimulating it.

01:57 But then you also have to account for what are all the different hormones working against it.

02:04 Like catecholamines, glucocorticoids and growth hormone.

02:09 If you can maintain blood glucose within this level, of about 60 to 100 milligrams, you can have an optimal delivery of glucose to the brain.

02:22 This is helpful in times of trying to stave off hypoglycemia.

02:26 And maybe we've all experience this one time or another, when you've been really light headed because you haven't eaten enough glucose.

02:34 Hyperglycemia is major health issue.

02:36 Specially if it' chronic hyperglycemia.

02:38 You can have small times in which you're blood glucose is above normal.

02:48 That's okay.

02:49 You're kidneys will take care of it by filtering out that excess glucose and you'll urinate it out.

02:55 But if you have high blood glucose levels for long periods of time, such as those that have diabetes.

03:03 This can be very problematic to a number of basal membranes such as blood vessels as well as even to nerves.

03:12 Damaging blood vessels and nerves can cause very big problems with the circulation and your ability to sense the external environment.

03:23 In fact renal function is another thing that is compromised to a great degree if a person has hyperglycemia for long periods of time.