Hypothalamus

anterior pituitary

aka adenohypophysis

contain granular cells

secrete 6 hormones into blood

derived from ectoderm of primitive mouth 

posterior pituitary

aka neurohypophysis

NO granular cells

has axons

derived from neuroectoderm of neural tube

Where does ipRGC project to?

suprachiasmatic nucleus → pineal gland → control circadian rhythm

Hormones released by ant pituitary

ACTH

GH

Prolactin

TSH

LH

FSH

Hormones released by post. pituitary

vasopressin

oxytoxin

what kind of cells release the hormones from ant. pit. ?

grandula cell

Arcuate nucleus

secretes releasing or inhibitory factors to control the ant pit

hypothalamic neurons

release hormones to the post pit

cell bodies lie in the supraoptic and paraventricular nuclei

What can happen when a pt have ADH and ACTH deficiency?

diabetes inspires: kidney produces diluted urine

a lesion on the optic chasm can cause:

bi-temporal VF defect

pituitary adenoma

common benign tumors

large tumors compress optic chiasm/optic nerve → vision loss

functional adenoma

• prolactinoma: overproduces prolactin → irregular periods, galactorrhea (milky breast discharge) in women, diminished sexual drive in men

• acromegaly (adult), gigantism (child) - excessive GH

• Cushing’s disease: overproduction of cortisol → weight gain, thin skin, stretch marks

nonfuctioning adenoma

do not secrete active hormones

sympathetic

fight or flight

T1-L3

IPSILATERAL

signal send to pre-ganglionic in SPINAL CORD uses Acetylcholine → post ganglionic trunk → target by norepinephrine

EXCEPT FOR SWEAT GLAND which only uses Acetylcholine

CNS → short pre gang fiber using Ach → long post gang using NE

parasympathetic

rest or digest

in the brain stem

uses Acetylcholine

signal send to ganglion CLOSE TO TARGET → target

CNS → long pre-ganglionic fiber using Ach → heart, smooth muscles, glands

oculosympathetic pathway

ipsilateral

1st order: hypothalamus → brainstem → spinal cord → synapse at C8-T2

2nd order (preganglionic axons) : C8-T2 → lung apex → subclavian artery → superior cervical ganglion

3rd order (post ganglionic fiber/carotid plexus): superior cervical ganglion -> internal carotid artery → cavernous sinus → leaves ICA joins CN VI → ophthalmic branch of trigeminal nerve V1→ iris dilator

innervate Mullers muscle (upper lid)

Neuron order for Oculosympathetic pathway

first order neuron: axon depends from hypothalamus → C8-T2 in spinal cord

second: axons travel near the lung and shoulder and snaps at the superior cervical ganglion

third order: post ganglionic axon travel to the carotid plexus → cavernous sinus → CN VI → trigeminal nerve -) iris dilator muscle

also innervate Muller’s muscle (upper lid), subomotor vasoconstrictor of forhead

Horner’s syndrome

oculosympathetic pathway is disrupted somewhere

slight ptosis (droopy lids)

small pupil (ipsilateral)

low sweating over brows and face

does not affect vision

ciliary ganglion

CN 3 → ciliary ganglion → pupillary constrictor and ciliary muscle

pterygopalatine ganglion

pons → CN VII → lacrimal gland

submandibular ganglion

pons → CN 7 → submandibular ganglion → submandibular and sublingual glands

otic ganglion

CN IX → otic ganglion → parotid gland

target / parasympathetic(receptor)

iris sphincter muscle / pupil constriction (M3)

ciliary muscle / accommodation (M3)

salivary and lacrimal gland / stimulation (M3)

target / sympathetic (receptor)

iiris dilator muscle / pupil dilation (alpha 1)

Lid’s Muller’s muscle / raises eyelids (a1)

sweat glands / stimulation (M3)

Parasympathetic Ganglion

• Ciliary Ganglion

• Otic Ganglion

• Pterygopalatine Ganglion

• Submandibular Ganglion