Powerpoint 5 Flashcards
What 5 different hormones does the pituitary gland secrete and what sub-gland do each of these hormones act on?
- Prolactin (PRL) –> lactation
- Thyrotrophin / thyroid stimulating hormone (TSH) –> act on thyroid gland
- Adrenocorticotrphin (ACTH) –> action on the adrenals
- Luteinizing hormone (LH) and follicle stimulating hormone (FSH) –> act on the gonads (ovaries and testes)
- GH
What controls the pituitary gland?
The nervous system via the hypothalamus
Pituitary gland:
- Weight
- Diameter
- Size
- 0.5-1.0 g
- 1 cm diameter
- pea
By how much % does the pituitary gland increase in size during pregnancy?
30%
The hypothalami-hypophyseal tract is derived from two different _______ components.
ectodermal (outermost layer of cells or tissue of an embryo in early development)
What is the anterior pituitary derived from?
Rathke’s Pouch: outgrowth of the buccal cavity detaches itself and becomes anterior pituitary
What is the posterior pituitary derived from?
The infundibulum develops from an outgrowth of the neuro-ectoderm from the floor of the 3rd ventricle. It gives rise to the pituitary stalk, the median eminence and the POSTERIOR PITUITARY
The _______ pituitary is highly vascularized.
anterior: note capillary bed in median eminence connected to portal veins the a 2nd capillary bed in anterior pituitary - some retrograde flow to allow hormonal feedback from pituitary to hypothalamus (short loop)
What hormones does the hypothalamus relay to the posterior pituitary?
vasopressin
oxytocin
Which section of the neurosecretory neuron of the hypothalamus relays vasopressin to the posterior pituitary?
Pupraoptic
Which section of the neurosecretory neuron of the hypothalamus relays oxytocin to the posterior pituitary?
Paraventricular nucleus
The posterior pituitary is an _______ of the hypothalamus.
extension
When using the term “Hypothalamic Nuclei” what does Nuclei refer to?
The cell bodies of the neurons which produce the hypothalamic hormones
What two nuclei are associated with the posterior pituitary?
- Supraoptic nuclei
2. Paraventricular nuclei
What nuclei is associated with the anterior pituitary?
Hypothalamic-hypothysiotropic nuclei
The hypothalamus receives signals from all areas of the brain - what do these signals trigger?
They trigger exocytosis of hormone vesicles from the axon terminal endings
Which 5 neurotransmitters are involved in sending signals to hypothalamus?
- neuro-epinephrine
- epinephrine
- dopamine
- serotonin
- acetylcholine