Glucocorticoids
Chemistry and Pharmacodynamics Chemical structure Glucocorticoids are synthetic analogs of cortisol and cortisone. Alterations may include: Fluorination (dexamethasone, betamethasone) Methylation (methylprednisolone) Physiology Endogenous glucocorticoids are: Derived from cholesterol (which is synthesized from acetyl-CoA) Secreted from the zona fasciculata Effects: respond to immediate stressors ↑ Immediate available energy through: Fat and protein catabolism → ↑ blood […]
Insulin
Pharmacodynamics Chemistry Insulin is a small protein normally created and released by pancreatic beta cells. Available formulations can be: Human insulin: identical to endogenously produced insulin Analog insulin: altered to create pharmacokinetic advantages Mechanism of action Insulin acts on cells to ↑ glucose uptake in all tissues, including the: Liver Skeletal muscle Adipose tissue This […]
Adrenal Glands: Anatomy
Overview Location There are 2 adrenal glands in the body and each gland is in close association with a kidney. The adrenal glands are: Borders/anatomic relations Development Gross Anatomy General structure The adrenal glands are composed of 2 functionally separate layers: the adrenal cortex and the adrenal medulla. Each layer has its own embryologic origins, […]
Hypothalamus
Development The hypothalamus is a collection of various nuclei within the center of the brain that develops early during embryologic life. Neural tube The 1st step is development of the neural tube. Primary and secondary neural vesicles The neural tube develops 3 “bulges” known as the primary vesicles: Gross Anatomy Location Boundaries Table: Boundaries of […]
Gonadal Hormones
Overview Definition Gonadal hormones: The gonadal hormones are produced by the human gonads: the testes and ovaries. These hormones include: Gendered terminology: Recognizing the complexity and sensitive nature around gendered terminology, for the purposes of this document: Hypothalamic-pituitary-gonadal (HPG) axis Hormones secreted by the gonads are stimulated by, and help to regulate, the hypothalamic-pituitary-testicular (HPT) […]
Hypothalamic and Pituitary Hormones
Overview Definitions Hormones are messenger molecules that are synthesized in one part of the body and exert specific regulatory effects on another part of the body. Hypothalamic hormones: Secreted directly by neurons from the hypothalamus Act on the pituitary gland Represent the point of integration between the CNS and endocrine system Pituitary hormones: Secreted from […]
Adrenal Hormones
Overview Regions of the adrenal gland The adrenal glands have 2 primary areas with separate functions and regulatory mechanisms. Hypothalamic-pituitary-adrenal (HPA) axis Hormones secreted by the adrenal cortex (not the medulla) are controlled by, and help regulate, the HPA axis. Adrenal Cortex Hormones: Mineralocorticoids Mineralocorticoid overview The renin-angiotensin-aldosterone system (RAAS) The RAAS is one of […]
Pituitary Gland: Anatomy
Overview The pituitary gland is known as the “master endocrine gland.” This gland receives stimulatory input from the hypothalamus and secretes multiple different hormones, which target multiple different end organs and have wide-ranging effects throughout the body. Location General structure The pituitary gland is divided into 2 primary components: The 2 halves function independently, as […]
Thyroid Hormones
Overview Hormones released by the thyroid gland The primary hormones released from the thyroid include: The thyroid hormones, triiodothyronine (T3) and thyroxine (T4): Produced by follicular cells Act on most cells/tissues in the body Stimulate metabolism and oxygen consumption → primary regulators of body metabolism Increase circulation and respiration Promote nervous system and skeletal development […]
Hormones: Overview and Types
Hormones and Endocrine Glands Definition Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. General functions of hormones Major functions of hormones include: Endocrine glands and organs The major endocrine glands in the body include: […]