Class Notes (808,893)
United States (313,366)
Biology (292)
BIL 360 (21)
Lecture 11

BIL 360 Lecture 11: Endocrine Control of Nutrient Metabolism

3 Pages
Unlock Document

University of Miami
BIL 360
Dubois Adrienne

Endocrine Control of Nutrient Metabolism ❖ Cells require a continuous supply of nutrients, and the management of nutrients is under endocrine control ➢ Storage ➢ Mobilization ➢ Interconversion ❖ Important hormones ➢ Insulin and glucagon produced in pancreas of islets of Langerhans ❖ During digestion stimulate beta cells to produce insulin ➢ Breaking down large macromolecules ➢ Stomach and intestines break down large macromolecules ▪ Release of glucose stimulate beta cells to produce insulin ▪ Gastrin hormone produced in the stomach also activates beta cells ➢ Parasympathetic nervous system ➢ Combination and each of these stimulate beta cells ❖ Insulin ➢ Facors storage of carbs, amino acids, fatty acids from ▪ Fat or adipose tissue ▪ Bind to insuling receptors and begin series of signal transduction events that lead to glucose transporters ▪ Insulin binds to receptors on muscle fiber and initiate a signal cascade ➢ Allos cells to take up glucose through facilitated diffusion ➢ Increase insulin causes decrease in glucose ▪ Hypoglycemic affect ➢ Insulin also stimulates target cells that synthesize ▪ Glycogen – storage • Takes the small subunits and build them up ▪ Triglycerides • Short chain fatty acids ▪ Proteins from glucose ▪ Fatty acids ▪ AAs ➢ Everything is favoring storage compounds and inhibit the synthesis of molecules that would typically break these down ❖ Graphs ➢ As blood glucose levels increase following a meal rich in carbohydrates insulin will go down ▪ Lack of insulin causes diabetes or insensitivity to insulin (when cells lack sensitivity when insulin is released and stop taking up sugars in the blood) ➢ levels of insulin also increase to favor storage of digested compounds from the meal ❖ Glucagon ➢ Keeps blood glucose levels stable in the body when working with insulin ➢ Conversely to insulin stimulated by low blood glucose levels ➢ Sympathetic nervous system activation of alpha cells ➢ Opposite affects of what insulin is doing ➢ As opposed to affects of insulin which is favoring storage glucagon favors break down of glycogen ▪ Glycogenolysis ▪ Stimulates gluconeogenesis (type of interconversion of nutrients) – liver can take things and convert them to glucose ▪ Inhibits triglyceride formation, stimulates fatty acid, protein release • Hyperglycemic effect ➢ Mobilizing nutrients ▪ Release into blood stream ▪ Break down storage molecules that already exist ➢ As blood glucose increases negative feedback mechanisms causes glucagon levels to go back down ❖ Carbohydrate meal ➢ Glucagon is secreted in unfed states ➢ Rise of insuling in response of increase is plasma glucose concentration ➢ Glucagon relatively high until the meal starts ❖ Protein meal ➢ Normally glucagon release in unfed or fasting state ➢ Acting to take stored nutrients and release them to be used ➢ High in protein we see high glucagon levels as well and low carbohydrate ➢ Glucose concentration doesn’t change too much ➢ Insulin triggered (rise) favoring binding up of AAs into larger molecules for
More Less

Related notes for BIL 360

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.