endocrine microanatomy

• What are endocrine organs primarily composed of?

  Glands widely separated from each other
• What is the primary function of endocrine organs?

  Maintain homeostasis and coordinate growth
• How do endocrine organs disseminate hormones?

  Through the bloodstream from secretory cells
• What is the developmental origin of endocrine glands?

  They begin as down-growing buds of cells
• Where is the pituitary gland located?

  Hanging from the hypothalamus
• What is the role of the hypothalamus in relation to the pituitary gland?

  Provides a neural link to the endocrine system
• What are the two parts of the pituitary gland?

  Anterior pituitary and posterior pituitary
• What are chromophils in the anterior pituitary?

  Brightly stained glandular cells
• What are the two types of chromophils?

  Acidophils and basophils
• What are chromophobes in the anterior pituitary?

  Pale staining exhausted or quiescent chromophils
• What hormone do somatotrophs produce?

  Growth hormone
• What percentage of anterior pituitary cells are mammotrophs?

  20%
• What hormone do corticotrophs produce?

  ACTH
• What is the function of the posterior pituitary?

  Stores and releases hormones from axons
• What hormones are secreted by the axons from the supraoptic nucleus?

  ADH
• What are Herring bodies?

  Dilations of axons for hormone storage
• What is the primary function of the thyroid gland?

  Regulate metabolism and calcium levels
• What is a goitre?

  Swelling of the neck due to thyroid issues
• What do follicular cells of the thyroid produce?

  T3 and T4 hormones
• What is the role of parafollicular cells in the thyroid?

  Produce calcitonin to lower blood calcium
• What is thyroglobulin?

  Inactive storage form of T3 and T4
• How is thyroglobulin converted to T3 and T4?

  By lysosomal action stimulated by TSH
• Where are adrenal glands located?

  On superior poles of the kidneys
• What does the adrenal cortex produce?

  Mineralocorticoids, glucocorticoids, androgens
• What is the function of the zona glomerulosa?

  Produce mineralocorticoids like aldosterone
• What does the zona fasciculata produce?

  Glucocorticoids like cortisol
• What do the islets of Langerhans in the pancreas secrete?

  Glucagon, insulin, somatostatin, polypeptides
• What is the function of enteroendocrine cells?

  Control local gut function by secreting hormones
• What hormone does gastrin stimulate?

  Gastric acid secretion
• What is the oral impact of hyperthyroidism?

  Accelerated dental eruption and osteoporosis
• What are the oral impacts of hypothyroidism?

  Delayed eruption and macroglossia
• What are the main functions of the endocrine system?

  • Maintain homeostasis
  • Coordinate body growth and development
  • Disseminate hormones to bloodstream
  • Cause changes in metabolic activity
• What are the types of cells in the anterior pituitary and their functions?

  • Chromophils: hormone-producing cells (acidophils, basophils)
  • Chromophobes: exhausted or quiescent chromophils
  • Somatotrophs: produce growth hormone
  • Mammotrophs: produce prolactin
  • Corticotrophs: produce ACTH
  • Thyrotrophs: produce TSH
  • Gonadotrophs: produce FSH and LH
• What are the layers of the adrenal cortex and their functions?

  • Zona glomerulosa: produces mineralocorticoids (e.g., aldosterone)
  • Zona fasciculata: produces glucocorticoids (e.g., cortisol)
  • Zona reticularis: produces androgens for sex
• What hormones are secreted by the pancreas and their functions?

  • Alpha cells: secrete glucagon
  • Beta cells: secrete insulin
  • Delta cells: secrete somatostatin
  • F cells: secrete pancreatic polypeptides
• What are the effects of hyperthyroidism and hypothyroidism on oral health?

  Hyperthyroidism:

  • Accelerated dental eruption
  • Osteoporosis
  • Increased risk of caries
  • Periodontal disease

  
  

  Hypothyroidism:

  • Delayed eruption
  • Enamel hypoplasia
  • Macroglossia
  • Micrognathia
• What type of staining is characteristic of the posterior pituitary?

  Pale staining
• What is the composition of the posterior pituitary?

  Unmyelinated axons of neurosecretory cells
• Where are the neurosecretory cell bodies of the posterior pituitary located?

  Supraoptic and paraventricular nuclei
• What hormone is associated with axons from the supraoptic nucleus?

  Antidiuretic hormone (ADH)