anatomy of the pituitary and cavernous sinus Flashcards
Chemicals secreted from the anterior pituitary
- Somatotrophs: growth hormone
- Thyrotrophs: TSH
- ACTH from corticotrophs
- Gonadotrophs secrete FSH and LH
- Lactotrophs = prolactin
Chemicals from posterior pituitary
Oxytocin
ADH - constricts arterioles to increase peripheral vascular resistance and raise arterial BP
Which hole does the maxillary nerve emerge from?
Rotundum
Which hole does the mandibular nerve arise from?
Ovale
where is the superior sagittal sinus?
Between falx and back of skull
Where does the anterior pituitary arise from?
foregut - Rathke’s pouch (ectoderm)
Where does the posterior pituitary arise from?
Downwards growth of brain - connected by pituitary stalk
Parts of anterior pituitary
Pars distalis - from anterior wall of rathe’s pouch
Pars tuberalis - surrounds anterior aspect of infundibular stalk
Pars intermedia - thin layer of epithelial cells between pars distils and neurohypophysis
Pituitary portal venous system
Blood vessels connecting hypothalamus with anterior pituitary - exchanges hormones via pituitary stalk
Peptides released from hypothalamus
GnRH
CRH
GHRH
TRH
Pituitary pathology
Bitemporal hemianopia, Cushing’s, galactorrhea and CN3 palsy
Types of pituitary adenoma
Functioning vs non-functioning
<1cm is micro adenoma, >1cm is macro
Compression of cavernous sinus causes
CN palsies
Compression of diaphragm sella causes
Headache
What happens to prolactin levels when you have no dopamine?
No inhibitory effect = lots of prolactin
