The Neuroendocrine System Flashcards
Describe the pituitary gland (location, housing, connection to hypothalamus and two parts)
-Pea sized structure located below the hypothalamus and optic chiasm
-housed in the Sella Turcica
-connected to the hypothalamus via the infundibulum (pituitary stalk)
two parts:
-Anterior - glandular tissue (adenohypophysis)
-Posterior - neural tissue (neurohypophysis)
What are the six hormones synthesized by the anterior pituitary?
growth hormone (GH), thyroid stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), lutenizing hormone (LH), and prolactin (PRL)
Growth hormone (GH)
Synthesized in the anterior pituitary and causes the liver, kidneys and other organs to produce growth factors that promote increased bone growth
Thyroid stimulating hormone (TSH)
Synthesized in the anterior pituitary and stimulates the thyroid gland to produce thyroxine (T4) and triiodothyronine (T3) (hypothalamus pituitary thyroid axis)
Adrenocorticotropic hormone (ACTH)
Synthesized in the anterior pituitary and stimulates adrenal cortex to produce corticosteroid hormones, especially cortisol (hypothalamus pituitary adrenal axis)
Follicle-stimulating hormone (FSH)
Synthesized in the anterior pituitary and along with LH, regulates menstrual cycle and oogenesis in women and regulates testicular hormones and spermatogenesis in men (hypothalamus pituitary gonadal axis)
Lutenizing hormone (LH)
Synthesized in the anterior pituitary (and along with FSH) regulates the menstrual cycle and oogenesis in women and regulates testicular hormones and spermatogenesis in men
Prolactin (PRL)
Synthesized in the anterior pituitary and promotes milk production
What hormones are synthesized by the posterior pituitary (neurohypophysis)?
There are NO HORMONES synthesized here. The posterior pituitary only stores hormones and releases them into the blood – it does not synthesize them.
What is the portal system formed by the hypothalamus and anterior pituitary?
the hypothalamic-hypophysial portal system
The hypothalamus and posterior pituitary form what type of system?
Form a neurosecretory system, that is to say:
• Cell bodies are in the hypothalamus
• Axons terminate on capillaries in the posterior pituitary
Which hormones are secreted from the posterior pituitary?
Vasopressin (AKA antidiuretic hormone-ADH) and Oxytocin
Vasopressin (AKA: antidiuretic hormone-ADH)
(synthesized by the hypothalamus and released from the posterior pituitary) enhances water retention by the kidneys
Oxytocin
(synthesized by the hypothalamus and released from the posterior pituitary) stimulates contraction of uterine smooth muscle during birth; promotes ejection of milk
What nuclei are found in the preoptic region of the hypothalamus?
Medial and lateral preoptic nuclei
What nuclei are found in the anterior (supraoptic) region of the hypothalamus?
Periventricular nucleus Suprachiasmatic nucleus Lateral hypothalamic nucleus Anterior nucleus Paraventricular nucleus Supraoptic nucleus
What nuclei are found in the middle (tuberal) region of the hypothalamus?
Periventricular nucleus Arcuate nucleus Dorsomedial nucleus Lateral hypothalamic nucleus Ventromedial nucleus
What nuclei are found in the posterior (mamillary) region of the hypothalamus?
Posterior nucleus
Mammillary body
Lateral hypothalamic nucleus
Which hypothalamic nuclei play a role in the autonomic nervous system (sympathetic and parasympathetic)?
Paraventricular nucleus
Dorsomedial nucleus
Lateral hypothalamic
Which structures in the hypothalamus play a role in the limbic system (connections with the hippocampal formation, amygdala, and thalamic nuclei)?
Mamillary bodies
The suprachiasmatic nucleus plays a major role in what additional function of the hypothalamus?
Regulation of Circadian rhythm/sleep
The lateral and ventromedial nuclei play a major role in what additional function of the hypothalamus?
Regulating appetite and thirst
The anterior and posterior nuclei play a major role in what additional function of the hypothalamus?
Thermoregulation
Thyrotropin-releasing hormone (TRH)
Produced by: Paraventricular nucleus
Effect: Stimulate thyroid-stimulating hormone (TSH) release from the anterior pituitary (primarily)
Corticotropin-releasing hormone (CRH)
Produced by: Paraventricular nuclus
Effect: Stimulate adrenocorticotropic hormone (ACTH) release from the anterior pituitary
Prolactin-inhibiting hormone (PIH)
Produced by: Arcuate nucleus
Effect: Inhibit prolactin release from anterior pituitary
Growth hormone-releasing hormone (GHRH)
Produced by: Arcuate nucleus
Effect: Stimulate Growth hormone (GH) release from the anterior pituitary
Lutenizing hormone-releasing hormone (LHRH)
Produced by: Preoptic area
Effect: Stimulate follicle-stimulating hormone (FSH) and lutenizing hormone (LH) release from the anterior pituitary
Growth hormone-inhibiting hormone
Produced by: Periventricular nucleus
Effect: Inhibit Growth hormone (GH) release from anterior pituitary
Oxytocin (OXY or OXT)
Produced by: Paraventricular nucleus and Supraoptic nucleus
Effect: Uterine contraction and lactation (letdown reflex)
Vasopressin (AKA: antidiuretic hormone-ADH)
Produced by: Paraventricular nucleus and Supraoptic nucleus
Effect: Increase in the permeability of water of the cells of distal tubule and collecting duct in the kidney thus allowing water reabsorption and excretion of concentrated urine.
Which hormones are produced by the Paraventricular nucleus?
Thyrotropin-releasing hormone (TRH), Corticotropin-releasing hormone (CRH), Oxytocin (OXY or OXT) and Vasopressin (antidiuretic hormone ADH or AVP)
Which hormones are produced by the Arcuate nucleus?
Prolactin-inhibiting hormone (PIH) and Growth hormone-releasing hormone (GHRH)
Which hormones are produced by the Preoptic area of the hypothalamus?
Lutenizing hormone-releasing hormone (LHRH)
Which hormones are produced by the Periventricular nucleus?
Growth hormone-inhibiting hormone (GHIH)
Which hormones are produced by the Supraoptic nucleus?
Oxytocin (OXY or OXT) and Vasopressin (antidiuretic hormone ADH or AVP)
