The hypothalamo-hypophyseal systems. The pituitary gland.

The hypothalamo-hypophyseal systems.

The pituitary gland

Regulation of endocrine organs

Közp. idegr.

Releasing hormon (pl. CRF)

Adenohypophysis sejt (pl. corticotrop)

Glandotrop hormon (pl. ACTH)

Neurosecretion: secreration of neruon

gets into the bloodstream

Negative feedback: hormons of target

organ inhibit the adenohypophysis

- Median eminence

Pituitary gland: parts

Embryology: Rathke’s pouch + floor of diencephalon

Problem: craniopharyngioma tumors

Acidophil: GH, PROL

Secreted hormone Abbreviation Produced by Effect

Oxytocin Magnocellular neurosecretory cells

Uterine contractionLactation (letdown reflex)

Vasopressin(antidiuretic hormone)

ADH Magnocellular neurosecretory neurons

Increase in the permeability to water of the cells of distal tubule and collecting duct in the kidney and thus allows water reabsorption and excretion of concentrated urine

Portal circulation

Secreted hormone Abbreviation Produced by Effect

Thyrotropin-releasing hormone

TRH, TRF, or PRH

Parvocellular neurosecretory neurons

Stimulate thyroid-stimulating hormone (TSH) release from anterior pituitary (primarily)

Dopamine(Prolactin-inhibiting hormone)

DA or PIHarcuate nucleus

Inhibit prolactin release from anterior pituitary

Growth hormone-releasing hormone

GHRHArcuate nucleus

Stimulate Growth hormone (GH) release from anterior pituitary

Somatostatin(growth hormone-inhibiting hormone)

SS, GHIH, or SRIF

Periventricular nucleus

Inhibit Growth hormone (GH) release from anterior pituitaryInhibit thyroid-stimulating hormone (TSH) release from anterior pituitary

Gonadotropin-releasing hormone

GnRH or LHRH

Preoptic area

Stimulate follicle-stimulating hormone (FSH) release from anterior pituitaryStimulate luteinizing hormone (LH) release from anterior pituitary

Corticotropin-releasing hormone

CRH or CRFParvocellular neurosecretory neurons

Stimulate adrenocorticotropic hormone (ACTH) release from anterior pituitary

(1) Chromophils Acidophils - Somatotrophs - Mammotrophs Basophils - Thyrotrophs - Corticotrophs - Gonadotrophs

(2) Chromophobes

Herring bodies (Gömöri / chrome haematoxylin phloxine)

3.: Bitemporal hemianposia