Endocrinology Flashcards Preview

Physiology > Endocrinology > Flashcards

Flashcards in Endocrinology Deck (659)
Loading flashcards...
151

  1. General facilitator
  2. Peptide family actin on gastrin

152

  1. PRL+, GH+, TSH+
  2. Paracrine action of tachykinins in HP

153

  1. PRL+

154

The function of: Vasoactive intestinal peptide (VIP)

  • PL+
  • Somatostatin-

155

The function of: Angiotensin-II

  • Synthesis + release of somatotropin + prolactin
  • MSH-inhibiting effect

156

  1. Stimulation of water reabsorption
  2. Increase BP, V1 receptor, IP3

 

157

  1. Preparation of uterine contractions for estrogen response, basket cell contraction
  2. Classical neuroendocrine reflex

158

Give an example of neuroendocrine reflexes

Oxytocin-mechanisms

159

What are the essential characteristics of a neuroendocrine reflex?

  1. Translation of neural information from sensory nerve to the language of the endocrine system (using the hypothalamus)
  2. Effect/response is not neural but hormonal

160

Describe the reflexes for milk ejection

  1. Excitation from udder sensory fibres → Spinal cord
  2. Excitation → Hypothalamus
  3. Enhanced oxytocin synthesis evoked
  4. Oxytocin release increases from the neurohypophysis
  5. Oxytocin reaches the mammary gland via blood
  6. Contraction of myoepithelial cells (For milk ejection)

 

161

Give the hormonal profile of a cow in stress

  • Plasma glucocorticoid level increases, causing:
    • Oxytocin fall
    • Prolactin fall
    • Milk ejection decrease to minimum

162

What are glandotropic hormones?

Give examples

Those acting exclusively on endocrine glands

  • TSH
  • ACTH
  • FSH
  • LH

163

What are histiotropic hormones?

Give examples

Those acting on certain organs

  • STH
  • PRL

164

The adenohypophysis develops in which structure?

Rathke's pouch

165

The adenohypophysis is formed by...tissue

Entodermal glandular

166

The neurohypophysis is formed by...tissue

Ectodermal nervous

167

Give the cell types of the hypophysis

  • A = Acidophils
  • B = Basophils
  • C = Chromophobes

168

Somatotropin (GH) producing cells

169

Adrenocorticotropin (ACTH) producing cells

170

Thyrotropin (TSH) producing cells

171

Prepubertal hypopituitarism/Removal of the pituitary gland

  • Results in proportional dwarfism
  • In adults:
    • Smaller organs
    • Thin hairs
    • Decreased sexual function
    • Decreased protein/glycogen stores
    • Decreased BMR

172

Congenital hyperpituitarism

  • Gigantism
  • In adult life:
    • Acromegaly: Increase in the size of enlargeable extremities and other parts. E.g limbs

173

Metabotropic hormones of the hypophysis

  • GH
  • ACTH
  • TSH

174

Gonadotropic hormones of the hypophysis

  • PRL
  • FSH
  • LH

175

STH/GH receptor mechanism of action

  1. Hormone binds to the receptor
  2. IC conformational change
  3. Activation of the second messenger system
  4. = G-protein activated cAMP

176

What direct biological effect does GH have on the body?

  • Stimulates somatomedins (further hormones) in the liver
  • GH is therefore considered to be glandotropic + histiotropic

177

Increased growth hormone secretion in young age results in...

Gigantism

178

Increased growth hormone secretion in adults results in...

Asymmetrical growth of:

  • Limbs
  • Jaw
  • Certain flat bones

179

Give the episodic release of GH

180

The effect of growth hormone on protein metabolism

  • Increases amino acid uptake
  • Increases intracellular protein synthesis
  • Positive nitrogen balance