Animal Science 434 - Endocrinology
Special thanks to the manufactures of the Target and Accufirm milk progesterone assay kits which were donated for use in this teaching laboratory.
As of Fall 2007, Accufirm is no longer distributed within the US and you will not be able to do this assay in the laboratory. In 2015 this also occured for the Tartget assay. In 2016 we retain information on both the Accufirm and Target Milk Progesterone assays so you can learn how an ELISA works. In 2017 we have added a section on pregnancy associated glycoproteins (PAGs) to detect pregnancy in cattle. All ELISA assays are now under one of the lab activities.
Objective:
- Examine how the endocrine system works.
- Learn how to measure hormones using ELISA systems.
- Practice correct pipetting techniques.
- Determine how we use hormones to manipulate animal and human physiology.
Terminology:
- radioimmunoassay (RIA) - an immunologic assay that quantifies hormones or other immunogenic substances using radiolabeled hormones.
- enzyme-linked immunosorbent assa (ELISA) - a method of detecting and quantifying hormones utilizing an enzyme-linked antibody that produces an identifying color in the presence of the appropriate substrates.
- steroid hormone - a type of hormone that contains a series of carbon rings and is fat soluble.
- progesterone - a steroid hormone produced in the corpus luteum, that promotes maintenance of pregnancy, inhibits reproductive behavior and inhibits GnRH release.
- short chain amino acid hormone - a type of hormone that is made of a few to perhaps 50 amino acids. These hormones are produced from neural tissue and primarily come from the hypothalamus.
- gonadotropin releasing hormone (GnRH) - a short chain amino acid hormone made in the hypothalamus and causes LH and FSH release.
- oxytocin - a short chain amino acid hormone produced in the hypothalamus but released in the posterior pituitary. It causes contraction of smooth muscle in the uterus, vas deferens, and mammary gland.
- protein hormone - a type of hormone that is a protein
- peptide bond - a chemical bond between amino acids in a protein. This bond can be broken in the stomach and prevents these hormones from being taken orally.
- luteinizing hormone (LH) - a protein hormone produced in the anterior pituitary and causes ovulation or production of testosterone.
- human chorionic gonadotropin (hCG) - a protein hormone collected from urine of pregnant women and has LH-like activity.
Laboratory Activities:
- Getting ready for lab: In this section you will review classification schemes for hormones and view animations describing how to measure hormones in milk using a commercial ELISA.
- Structure, function and use: You will integrate how structure is related to mode of clinical hormone adminstration and some unusual uses of horomones.
- ELISA Assays: You will learn how to use an ELISA to measure progesterone in cow's milk, PAGs in Cow Blood and to detect pregnancy in human urine.
- BVD: Examine the consequences and prevention of this disease.
- Statistics: Evalutate the testis data from lab last week.
- Manipulation of hormones: Learn how hormones are manipulated in both domestic animals and humans to modify physiology. You will also make a powerpoint for next week about this topic and practice your presentation skills.
- Cow Project: You may need to start your synchronization scheme if you have not already done so. Be sure to review material on injection sites and CIDR insertion.