Pituitary Pathology and Puberty Flashcards
Which part of the trilaminar disc is the APG derived from? Where is the PPG derived from?
APG: Ectoderm
PPG: Floor of the third ventricles
What are the seven hormones that the APG produce?
FSH LH ACTH Growth Hormone TSH MelanOcyte Releasing Prolactin
What hormones does the PPG secrete and where are they synthesised?
H: ADH and Oxytocin
S: Para-ventricular and supra-optic nuclei
What are the functions of the 2 PPG hormones?
1) ADH: Water retention and release
2) O: a) Milk Secretion b) Uterine Contraction
What are the 3 main problems of a pituitary tumour?
1) Pressure on local structures e.g. Optic Chiasm
2) Hypo-pituitary
3) Functioning Tumour
What are the 2 causes and 5 signs of a prolactinoma and treatment?
a) Pituitary Adenoma b) Anti-dopaminergic drugs
1) Infertility 2) Galactorrhoea 3) Amenorrhoea 4) Loss of Libido 5) Visual field defects and headaches from local tumour effect
T: Dopaminergic Agonist
How is GH secreted from the anterior pituitary?
Pulsatile fashion –> Increased release during sleep
What are the main local effects of a pituitary adenoma?
1) Headaches
2) Visual field defects
3) CSF rhinorrhoea
4) CN palsy and temporal lobe epilepsy
What is puberty and what are the first tell-tale signs in M/F?
Morphological, physiological and behavioural changes of gonads infantile – > Adult
M: First-ejaculation (Night based)
F: Menarche
What hormones are responsible for Female growth and development?
Pub/Ax Hair: Ovarian and Adrenal androgens
Genitalia/Breasts: Ovarian androgens
What are the roles of testicular androgens in Male Development?
1) Development of external genitalia
2) Growth of pubic and axillary hair
3) Voice deepening
What is the name of the scale used to measure physical development based on external sex characteristics?
Tanner Scale
What is Thelarche and what are the 3 main stages?
Process of breast development (3 years, controlled by oestrogen)
1) Ductal Proliferation
2) Adipose Deposition
3) Areola and Nipple Enlargement
What is adrenarche and what are the 2 main signs of it?
Maturation of adrenal gland –> Zona Reticularis cells
Pre-pubertal adrenal androgen production
1) Body Odour 2) Mild Acne
What is pubarche?
Growth of pubic hair
What is precocious puberty and what is the treatment for it?
Onset of sexual characteristics before 8/9
T: GnRH super agonist to suppress pulsatility of GnRH secretion.
What is delayed puberty, most likely male cause, and 3 main consequences?
Delayed: Absence of characteristics by 14y/o and 16y/o
Male: Constitutional family delay –> Late menarche or delayed paternal growth spurt
1) Psychological problems
2) Reduced bone mass
3) Reproduction defects
What are the main functional causes of delayed puberty?
- Anorexia.
- Bulimia.
- Over exercising.
- CKD.
- Drugs.
- Stress.
- Sickle cell Disease
What tests would you run to check for delayed puberty?
- FBC - red cell count especially.
- U+E.
- LH/FSH measurements.
- TFT’s.
- Karyotyping for Turners.
What is adrenarche?
Development of the adrenal gland, with specialised cells forming the zona reticularis
What is a primary cause of hypogonadism?
Klinefelter’s Syndrome (Additional X chromosome)
How do hypogonadism and hypopituitarism affect testosterone and FSH/LH levels?
HG: Testosterone low FH/LSH high
HP: FSH/LH will be low, Testosterone low
How does androgen deficiency affect males?
1) Loss of libido
2) High pitched voice
3) Loss of facial, axillary, limb and pubic hair
4) Poorly developed scrotum and penis
5) Loss of erection
How is hypogonadism treated?
Injection of testosterone
