Download MBBS Physiology Presentations 8 Pituitary Hormones Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) 1st Year, 2nd Year, 3rd Year and Final year Physiology 8 Pituitary Hormones PPT-Powerpoint Presentations and lecture notes

Hypothalamus and Hypothalamo-

pituitary axis
Hypothalamus- Master of endocrine

Orchestra

Hypothalamo-pituitary-thyroid axis

Hypothalamo-pituitary ? adreno-cortical

axis

Hypothalamo-pituitary-gonadal axis

Hypothalamo-sympatho-adrenal axis

Hypophysiotropic hormones

TRH
CRH
GnRH
GRH
GIH/Somatostatin
PIH
PRH
Releasing hormones

Thyrotropin Releasing hormones (TRH)
-Secreted from paraventricular nucleus of

hypothalamus

-Stimulates TSH
-Also promotes GH and Prolacin
Gonadotropin Releasing Hormone (GnRH)
- Secreted by Arcuate nucleus of hypothalamus
- Stimulates LH, FSH

Releasing hormones

Corticotropin Releasing Hormone (CRH)
- Secreted

from

Paraventricular

nuclei

of

hypothalamus

- Stimulates ACTH
- Promotes POMC gene in corticotrophs
- Also promotes endorphins and lipotrophins

secretion

Growth hormone releasing hormone (GHRH)
- Secreted from arcuate nucleus of hypothalamus
- Stimulates secretion of GH
Prolactin releasing hormone (PRH)
-Stimulates prolactin secretion
Inhibiting Hormones

Growth hormone inhibiting hormone (GHIH)
-Secreted from anterior periventricular nucleus
- Inhibits growth hormone, prolactin, TSH

Prolactin Inhibiting hormone (PIH)
- Dopamine secreted from arcuate nucleus
- Inhibits Prolactin, TSH,GH

Kallaman's syndrome

Hypogonadotropic hypogonadism
Hyposmia or anosmia
Common in men
Mutation of KALIG1 gene on X

chromosome

Cell types in anterior pituitary

Somatotropes
Corticotropes
Thyrotropes
Gonadotropes
Lactotropes/Mammotropes
Hypopituitarism is marked by abnormal

pallor

Hyperpigmentation in adrenal

insufficiency

Effects of Pituitary insufficiency

Destroyed by disease- Supracellar cysts
Pituitary tumors
Postpartum necrosis ? Sheehan

syndrome

Remnanats of Rathke pouch

enlargement and compression of

pituitary
Hypopituitarism

Adrenal cortex atrophies
Stress induced aldosterone secretion is

absent

Growth is inhibited
Thyroid function is depressed
Gonads atrophy
Hypophysectomy ameliorates diabetes

mellitus

Diabetes Insipidus