1 Endocrine-Gland Histology Flashcards
Endocrine organs can be described as?
1) ductless
2) arranged into cords or follicles.
what does neuroendocrine mean?
signaling molecules are made by the cell body of a neuron and secreted into the blood stream to target cells.
Ex: ADH release from supraoptic nucleus
what does paracrine mean?
signaling molecules are secreted locally in dispersed into interstitial fluid to target cell.
Ex: G cells targeting chief cells
what is autocrine signaling?
the molecules act on the same cell that secreted them. This is a + feedback loop which can happen in T cells during activation.
what is juxtacrine signaling?
signaling molecules remain attached to secreted cells surface and effect the target cells when they make contact.
Ex: Notch signaling in heart development
what is endocrine signaling?
signaling molecules are secreted into the blood stream.
Ex: TSH that acts on the thyroid to release T3 and T4. (most common pathway)
What is DNES?
Diffuse Nueroendocrine System. Its the diffuse endocrine cells that make up the whole endocrine system.
what hormones are released from the pituitary gland?
ADH FSH LH ACTH GH TSH Oxytocin Prolactin Melanocyte releasing hormone
which hormones are made and released from the posterior pituitary gland?
none are made there, but ADH and Oxytocin are released.
what does the thyroid gland release?
calcitonin thyroid hormone (T3 and T4)
what do the parathyroid hormones release?
Parathryroid hormone
what do the adrenal glands release?
Cortisol
Epi
Norepi
what do the kidneys release?
renin
erythropoietin
calcitrol
what do the testis secrete?
andorgens
inhibin
what do the ovaries secrete?
estrogen
progesterone
inhibin
what does the hypothalamus secrete?
ADH and Oxytocin Gonadotropin releasing hormone Thyrotropin releasing hormone corticotrophin releasing hormone Growth hormone releasing hormone
what does the pineal gland release?
melatonin
what major hormones does the GI tract release?
CCK
Gastrin
Secretin
what hormones does the pancreas release?
Glucagon
insulin
somatostatin
what is the adenohypophysis? where does it form from?
1) the anterior pituitary gland.
2) It forms from an upgrowth of oral ectoderm.
what is the stomadeum?
the clump of oral ectoderm that eventually forms the anterior pituitary gland.
what are the 3 parts to the adenohypophysis?
1) pars tuberalis
2) pars intermediate
3) pars distalis
what is the remnant of an embryological space within the ectoderm upgrowth of the adenohypophysis called?
Rathke’s pouch
what is the neurohypophysis? what is it derived from?
1) posterior pituitary gland
2) composed of ectoderm that forms the diencephalon
The neurohypophysis has 6 major contributors (Inputs) which include?
1) Supraoptic nucleus
2) Paraventricular nucleus
3-5) Hypothalamo-hypophyseotrophic area (arcuate, periventricular, dorsal nuclei)
6) Median eminence
what is the neural stock of the neurohypophysis called? what about the tract or pathway? what is the lower enlarged part of the gland called?
1) infundibulum
2) hypothalamo-hypophyseal tract
3) pars nervosa
The supraoptic nucleus secretes what? paraventricular nucleus?
1) ADH
2) Oxytocin=paraventricular
what is the function of arcuate, periventricular, and dorsal nuclei in relation to the posterior pit. gland?
They produce pituitary regulating hormones.
where are the Rathke’s cysts found?
In the pars intermedia of the adenohypophysis
what are the 3 cell types that we need to know in the anterior pituitary gland?
1) acidophils
2) basophils
3 chromophobes
What is the median eminence?
The site of storage and release of hypothalamic regulatory hormones.