Endocrine I: Pituitary, Pineal, and Medulla Flashcards
What are exocrine glands?
Glands with ducts that secrete non-hormones via ducts onto epithelial surfaces
What part of the cranium houses the pituitary gland?
The sella turcica
What controls secretion of pituitary hormones?
The hypothalamus
From what is the posterior pituitary derived? What is its alternate name based on this?
Derived from a downgrowth of neuroectoderm– aka neurohypophysis
From what does the anterior pituitary develop?
An upgrowth of the roof of the primitive oral cavity called Rathke’s pouch
What are the subdivisions of the anterior pituitary?
Pars distalis, pars tuberalis, pars intermedia
What are the subdivisions of the posterior pituitary?
Pars nervosa and infundibulum
What are the functions of the posterior pituitary? what hormones does it contain?
Storage of oxytocin and ADH produced in the hypothalamus
What is the hypothalamo-hypophyseal tract?
Axons from paraventricular and supraoptic nulcei of the hypothalamus extending into the pars nervosa, where they release hormones
Where, specifically, is antidiuretic hormone (vasopressin) produced? Oxytocin?
ADH- supraoptic nucleus of the hypothalamus; Oxytocin- produced in the paraventricular nucleus of the hypothalamus
True or False: Axons within the neurohypophysis with secretory activity are myelinated
False
What glial cells support neurons within the posterior pituitary?
Pituicytes
What is the most numerous cell of the neurohypophysis?
Pituicytes
What are Herring bodies?
Swellings within axons of the posterior pituitary, which are sites of storage for neurosecretory material
What kind of hormone is primarily secreted by the anterior pituitary?
Tropic hormones
Histologically, what are the different types of cells in the pars distalis?
Chromophils (acidophils and basophils) and Chromophobes
What is the primary mechanism for regulating anterior pituitary hormone release?
Releasing and inhibitory factors released from the hypothalamus?
How are releasing and inhibiting factors from the hypothalamus transported to the anterior pituitary?
Hypophyseal portal system
What is a portal system?
A vascular system where blood travels from one capillary bed to another through a vein without first traveling to the heart?
What is the narrow zone of tissue between the pars distalis and the pars nervosa?
Pars intermedia
What is an adenoma?
Benign tumors of glandular origin
What is the outermost layer of the adrenal gland?
A dense connective tissue capsule
What are the developmental origins of the suprarenal gland?
Cortex is derived from mesoderm; medulla is derived from neural crest cells
What supplies blood to the adrenal glands? What supplies the cortex and medulla?
Superior, middle and inferior suprarenal aa which form a subcapsular plexus; short cortical arteries supply the cells of the adrenal cortex and long cortical arteries supply the medulla
