1. Hormones – An Introduction FSH – A peptide hormone

2. Method of Action – Steroid Hormones  Steroids transport via carrier proteins – why?  Movement through plasma membrane into cytoplasm of target  Interaction with specific receptors  Binding to response elements in target genes  Influence on transcription

3. AF1 DNA binding/Dimerisation Ligand Binding Steroid receptor structure Transact DBD NL Transact DNA Sequence – Differs, depending on receptor complex eg., GGTCAnnnTGACCC for estrogen receptor bound to ligand

4. Method of Action – Peptide Hormones  Interact with ligand bound receptor on plasma membrane – why?  Consequence of interaction with receptor is signal transduction – eg., activation of GTP, influence on adenylate cyclase/cAMP/protein kinase  Gene activation indirect, but signal amplification can be more rapid

5. G-Protein Coupled Receptor Function Richardson, 2001

6. Hypothalamic-Pituitary Axis: An Historical Perspective Michelangelo’s “Creation of Adam” Outline of Brain FUNCTIONAL ANATOMY OF THE HYPOTHALAMUS AND PITUITARY Chapter 3b - Ronald M. Lechan, M.D., Ph.D., and Roberto Toni, M.D.

7. Neurohypophysis= Posterior Pituitary (neurons that extend here have cell bodies in hypothalamus Adenohypophysis = Anterior Pituitary “Glandular”

8. Hypothalamic/Pituitary Axis – Vasculature and Gross Morphology Adapted from http://www.uwyo.edu/wjm/Repro

9. Pituitary Histology Note the differences in morphology and staining patterns (acidophilic vs basophilic) reflecting differences in secretions b/w cell types. Tissue is also highly vascularized GH, PRL secreting FSH, LH etc