Endocrinology and Renal Systems

The study of Endocrinology and Renal Systems examines the intricate and bidirectional relationship between hormones and the kidneys, which is fundamental to maintaining systemic homeostasis. This field explores how the kidneys act as both a target for hormones—such as antidiuretic hormone (ADH) and aldosterone, which precisely regulate water and electrolyte balance—and as an endocrine organ in their own right, producing critical hormones like renin for blood pressure control, erythropoietin for red blood cell production, and calcitriol for calcium metabolism. This complex interplay ensures the tight regulation of blood pressure, fluid volume, and mineral balance throughout the body.

1. Introduction to Neuroendocrine and Renal Physiology
   1. Core Concepts of Homeostasis
      1. Definition and Importance of Homeostasis
      2. Set Points and Normal Ranges
         1. Physiological Set Points
         2. Variability and Adaptation
         3. Circadian Rhythms and Set Point Variation
      3. Negative Feedback Mechanisms
         1. Basic Principles
         2. Components of Negative Feedback Loops
         3. Examples in Endocrine Systems
         4. Examples in Renal Systems
      4. Positive Feedback Mechanisms
         1. Basic Principles
         2. Physiological Examples
         3. Pathological Implications
      5. Feed-forward Control
         1. Anticipatory Responses
         2. Neural Pathways
         3. Hormonal Pathways
         4. Integration with Feedback Systems
   2. Overview of the Endocrine System
      1. Fundamental Principles
         1. Definition of Hormones
         2. Endocrine vs Paracrine vs Autocrine Signaling
         3. Hormone Specificity and Selectivity
      2. Major Endocrine Glands
         1. Hypothalamus
            1. Anatomical Structure
            2. Neurosecretory Cells
            3. Hypothalamic-Hypophyseal Portal System
         2. Pituitary Gland
            1. Anterior Pituitary Structure and Function
            2. Posterior Pituitary Structure and Function
            3. Hypothalamic-Pituitary Axis
         3. Thyroid Gland
            1. Anatomical Structure
            2. Follicular Organization
            3. C-Cells
         4. Parathyroid Glands
            1. Anatomical Location
            2. Chief Cells
            3. Oxyphil Cells
         5. Adrenal Glands
            1. Adrenal Cortex Zones
            2. Adrenal Medulla
            3. Functional Organization
         6. Pancreas
            1. Islets of Langerhans
            2. Alpha Cells
            3. Beta Cells
            4. Delta Cells
         7. Gonads
            1. Ovarian Structure and Function
            2. Testicular Structure and Function
      3. Chemical Classes of Hormones
         1. Peptide and Protein Hormones
            1. Structural Characteristics
            2. Synthesis Pathways
            3. Processing and Modification
            4. Storage Mechanisms
            5. Secretion Patterns
            6. Transport in Blood
            7. Receptor Interactions
         2. Steroid Hormones
            1. Cholesterol as Precursor
            2. Steroidogenic Pathways
            3. Synthesis Regulation
            4. Transport Proteins
            5. Cellular Uptake
            6. Metabolic Clearance
         3. Amino Acid Derivatives
            1. Catecholamines
               1. Synthesis from Tyrosine
               2. Storage and Release
               3. Degradation Pathways
            2. Thyroid Hormones
               1. Synthesis from Tyrosine
               2. Iodination Process
               3. Storage and Release
               4. Peripheral Conversion
      4. Hormone Transport and Metabolism
         1. Free vs Bound Hormones
            1. Equilibrium Dynamics
            2. Biological Activity
            3. Measurement Considerations
         2. Plasma Binding Proteins
            1. Albumin Binding
            2. Specific Binding Proteins
            3. Binding Protein Regulation
         3. Hormone Degradation
            1. Hepatic Metabolism
            2. Renal Clearance
            3. Target Tissue Metabolism
            4. Half-life Concepts
      5. Mechanisms of Hormone Action
         1. Cell Surface Receptors
            1. G Protein-Coupled Receptors
               1. Receptor Structure
               2. G Protein Types
               3. Coupling Mechanisms
            2. Tyrosine Kinase Receptors
               1. Receptor Structure
               2. Autophosphorylation
               3. Downstream Signaling
            3. Ion Channel Receptors
            4. Second Messenger Systems
               1. cAMP Pathway
               2. IP3/DAG Pathway
               3. Calcium Signaling
         2. Intracellular Receptors
            1. Steroid Hormone Receptors
               1. Nuclear Localization
               2. DNA Binding Domains
               3. Transcriptional Activation
            2. Thyroid Hormone Receptors
               1. Nuclear Receptor Family
               2. Coactivators and Corepressors
               3. Gene Expression Regulation
         3. Signal Transduction Pathways
            1. Protein Kinase Cascades
            2. Phosphatase Systems
            3. Cross-talk Between Pathways
         4. Regulation of Target Cell Sensitivity
            1. Receptor Up-regulation
            2. Receptor Down-regulation
            3. Desensitization Mechanisms
   3. Overview of the Renal System
      1. Gross Anatomy
         1. Kidney Location and Orientation
         2. External Kidney Structure
         3. Internal Kidney Structure
            1. Renal Cortex
            2. Renal Medulla
            3. Renal Pelvis
         4. Renal Blood Supply
            1. Renal Arteries
            2. Intrarenal Vascular Architecture
            3. Renal Veins
         5. Urinary Tract
            1. Ureters
            2. Bladder
            3. Urethra
      2. Microscopic Anatomy
         1. Nephron Types
            1. Cortical Nephrons
               1. Structure and Distribution
               2. Functional Characteristics
            2. Juxtamedullary Nephrons
               1. Structure and Distribution
               2. Functional Characteristics
         2. Glomerular Structure
            1. Glomerular Capillaries
            2. Bowman's Capsule
            3. Filtration Barrier
               1. Endothelial Layer
               2. Basement Membrane
               3. Podocyte Layer
            4. Mesangial Cells
         3. Tubular Structure
            1. Proximal Convoluted Tubule
               1. Cellular Structure
               2. Brush Border
               3. Transport Mechanisms
            2. Loop of Henle
               1. Descending Limb Structure
               2. Thin Ascending Limb
               3. Thick Ascending Limb
            3. Distal Convoluted Tubule
               1. Cellular Structure
               2. Transport Characteristics
            4. Collecting Duct System
               1. Principal Cells
               2. Intercalated Cells
               3. Structural Organization
      3. Fundamental Renal Processes
         1. Glomerular Filtration
            1. Filtration Forces
               1. Hydrostatic Pressures
               2. Oncotic Pressures
               3. Net Filtration Pressure
            2. Glomerular Filtration Rate
               1. Determinants of GFR
               2. Measurement Methods
               3. Normal Values
            3. Filtration Selectivity
               1. Size Selectivity
               2. Charge Selectivity
               3. Molecular Sieving
         2. Tubular Reabsorption
            1. Mechanisms of Reabsorption
               1. Passive Transport
               2. Active Transport
               3. Secondary Active Transport
            2. Sites of Reabsorption
               1. Proximal Tubule Reabsorption
               2. Loop of Henle Reabsorption
               3. Distal Tubule Reabsorption
               4. Collecting Duct Reabsorption
            3. Substance-Specific Reabsorption
               1. Glucose Reabsorption
               2. Amino Acid Reabsorption
               3. Sodium Reabsorption
               4. Water Reabsorption
         3. Tubular Secretion
            1. Mechanisms of Secretion
               1. Active Secretion
               2. Passive Secretion
            2. Sites of Secretion
               1. Proximal Tubule Secretion
               2. Distal Nephron Secretion
            3. Secreted Substances
               1. Organic Anions
               2. Organic Cations
               3. Potassium
               4. Hydrogen Ions
         4. Urine Formation and Excretion
            1. Urine Concentration Mechanisms
            2. Urine Dilution Mechanisms
            3. Final Urine Composition
            4. Micturition Process