ANTERIOR and POSTERIOR PITUITARY components?
- Pars tuberalis
- Pars intermedia
- Pars distalis
- Median eminence
- Pars nervosa
Most secreting cells in the thalamus form?
Blood supply of the Pituitary gland?
Posterior lobe nerve involvement?
Some nerves such as those from the Supraoptic and Paraventricular nuclei produce ADH and Oxcytocin, respectively, these are released by the synaptic terminals at the capillaries in the posterior lobe of the gland itself.
Hypophyseal Portal System?
Is a capillary networks in the median eminance are supplied by the superior hypophyseal artery. Before leaving the hypothalamus the capillary networks unite to form a series of large vessels that spiral around the infundibulum to reach the anterior lobe.
It is the vessels that carry blood between these two capillary beds that form the hypophyseal portal system.
Mechanism of Growth Hormone relaease and feedback?
GH-IH = Growth hormone-Inhibiting hormone
GH-RH = Growth hormone-Releasing hormone
Oxytocin and Prolactin release? Prolactin feedback?
- Regulates its own synthesis and release.
- Dopamine is secreted in the median eminence
- Prolactine is released from APG and acts negatively on the tuberoinfundibular dopamine (TIDA) neurons in hypothal.
During Pregnancy we see massive changes with placental lactogens that bypass the feedback as well as a switch from negative to positive feedback.
Suckling stimulus from child also plays a massive role in release.
Hormonal control of Male HPG axis?
The menstrual cycle hormone levels?
- Estrogen is partly the cause for the switch in feedback of LH causing a large spike of FSH and LH and thus ovulation.
- Progesterone is produced by the corpus luteum and maintained high in pergnancy
Binding of FSH and LH?
LH binds to thecal cells where as FSH binds onto the granulosa cells
Female estrogen feedback on HPG axis?
- Progesterone inhibits both APG and GnRH neuron
- estrogen produced by dominant follicles acts positively
If Heape Daddy kisses a 10 year old boy will he start puberty?
Puberty starts due to Kisspeptine neurons firing not from a kiss silly.