1 / 15

Lab this Week

This paper explores the objectives and findings of the study on the endocrinology of hormone supplementation. It addresses important questions such as the major objectives of the paper and provides a concise summary of their most important findings. The paper discusses glucose homeostasis, positive feedback, and the mechanisms that regulate plasma glucose concentration. It also examines the impact of insulin secretion and the factors that influence it. This text is prepared to be turned in to the lab instructor.

floyda
Télécharger la présentation

Lab this Week

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Lab this Week Endocrinology of Hormone Supplementation Write a paragraph in which you 1) identify the major objectives of the paper (the most important questions it addresses), and 2) a concise summary of their most important findings. Bring this text with you to lab, ready to turn in to the lab instructor.

  2. Classes this Week • Glucose Homeostasis:Ch 16A p.555-567 and Ch 16B.1 p. 569-580 • Endocrinology Chapter 11 A-D, F

  3. 1QQ # 3 for 10:30 Name on top edge, back side of paper Answer on blank side of paper. • Describe what would happen if a person were injected with a drug that acts like Interleukin-6? • How can a feedforward response be distinguished from a negative feedback response? • What is the difference between heat stroke and heat exhaustion, and how can they be distinguished by physical examination? • How do Tylenol and other NSAIDs minimize a fever?

  4. 1QQ # 3 for 11:30 Name on top edge, back side of paper Answer on blank side of paper. • Describe what would happen if a person were injected with a drug that acts like Interleukin-6? • How can a feedforward response be distinguished from a negative feedback response? • What is the difference between heat stroke and heat exhaustion, and how can they be distinguished by physical examination? • How do Tylenol and other NSAIDs minimize a fever?

  5. Positive feedback • Examples of Positive Feedback in Physiology • Heat stroke (diagrammed earlier) • formation of blood clot • menstrual cycling of female sex hormone concentrations • generation of action potentials in nerve fibers • uterine contractions during childbirth • Each of these examples terminate naturally (self limiting) • Inherently unstable but some are essential for life!

  6. Glucose Homeostasis Another detailed example of negative feedback

  7. Graph your daily caloric intake over a 48 hour period Phases:absorptive, post-absorptive, and fasting PlasmaGlucose ? ? Calories consumed 6am Noon 6am 6am Noon MN Noon MN 6pm 6pm Overlay absorptive and post-absorptive phases on the graph

  8. Homeostasis of Plasma Glucose Concentration • Why is too much plasma glucose harmful? • Plasma glucose concentration = glucose entering the plasma – glucose leaving the plasma • What are the mechanisms that regulate plasma glucose concentration? • What are the components of the negative feedback loop: • Glucose receptors? • Afferent pathway? • Integrator? • Efferent pathway(s)? • Effector organ(s)?

  9. Muscle AdiposeLiverNervousOther

  10. Fig. 16.01 Lipoprotein Lipase Absorptive Phase =“sinks” Entry requiresGlut-4 transporters Once inside, glucose is converted to something else, thereby maintaining a concentration gradientfor facilitated diffusion ofglucose into cells.

  11. Activates some enzymes, inactivates others Exercise (via an undescribed mechanism) increases the number of glucose transporters in muscle cell membrane Peptide hormone GLUT-4 ↑ plasma glucose →↑insulin secretion→↑glucose uptake into cells →↓ plasma glucose Diabetes mellitus: T1DM =beta cells fail to produce adequate insulin (5%) T2DM = target cells “resistant” (less responsive) to insulin

  12. Fig. 16.07 Identify sensors, afferent pathway,integrator,efferent pathway,effectors How is insulin secretion affected if plasma glucose is lower than set point? Which cell types have insulin receptors?

  13. Islets of Langerhans Typical vasculature: Artery-Arteriole-Capillary-Venule-Vein-Heart Liver Alpha cells secrete glucagon Beta cells secrete insulin Delta cells secrete somatostatin Hepatic portal system Route of blood Artery-Arteriole-Capillary in digestive tract-Portal Vessel- Capillary in liver-Venule-Vein-Heart

  14. ? Thinking about food, aroma, Factors that influence Insulin Secretion and other Incretins FF WHY? Glucose uptake, Storage, Lipogenesis The Integrator integrates multiple inputs

More Related