Endocrine Glands I Flashcards
Exocrine glands
release their secretory product into a system of ducts
Endocrine glands
release hormones into extracellular space which pass into bloodstream which transports them to their target organs (no ducts)
Hypothalamus
coordinates endocrine functions
integrates endocrine and ANS functions
Neurons in hypothalamus
synthesize and secretes neurotransmitters
Neurosecretory cells in hypothalamus
synthesize hypothalamic hormones
Neurosecretory hormones
transported down the axons to the axon terminal via vesicles
Which lobe is neural, which is glandular
posterior is neural
anterior is glandular
Path of neurosecretory hormones
1) transported down axons to axon terminal via vesicles
2) released into the primary capillary plexus
3) drain into hypophyseal portal veins
4) go to secondary capillary plexus in anterior love of pituitary gland
Chromophils
color friendly glandular cells
Chromophobes
don’t stain
Path of Somatotropin releasing hormone (S-RH)
- released from hypothalamic neurosecretory cells
- influences acidophilic somatotropes
- somatotropes synthesize somatropin (GH)
Growth Hormone
influences long bone growth in epiphyseal growth plates
increases cellular metabolism in skeletal muscle in adipose tissue
Gigantism
excessive GH in children
ex) somatotrophic adenoma
Acromegaly
excessive GH in adults
get excessive growth of hands, feet, facial bones, and jaw
prolactin releasing hormone
produced by neurons in hypothalamus transported into anterior pituitary stimulates mammotropes (lactotropes) to synthesize prolactin
prolactin
stimulates mammary gland growth during pregnancy. stimulates lactation following birth
Pituitary adenoma
large, benign tumor. compresses neural tissue
prolactinoma
causes vision deficients, galactorrhea, excessive release of prolactin
Corticotropin releasing hormone
secreted by hypothalamus
travels to anterior pituitary gland
stimulates coritoctropes
corticotropes release adrenocorticotrophic hormone
ACTH passes into general circulation to influence adrenal cortex
Thyrotropin releasing hormone
secreted by hypthalamus
stimulates basophilic thyrotropes in anterior pituitary
thyrotopes relase thyroid stimulating hormone
TSH passes into general circulation to influence thyroid gland
Gonadotropin Relasing Hormone
secreted by hypothalamus
Gn-RH stimulates basophilic gonadotropes
Gonadotropes release follicle stimulating hormone and leutinizing hormone
Supraoptic and Paraventricular nuclei
are in hypothalamus
axons are bunched in the hypothalamohyophyseal tract and are not myelinated
Neurosecretory cells
synthesize ADH (vasopresson) and oxytocin
ADH and oxytocin axons form
hypothalamohypophyseal tract