Endocrine Glands and Hormones Flashcards
Where do you find the hypothalamus and pituitary?
Brain
What endocrine gland do you find at the neck?
Thyroid and parathyroid
What endocrine glands can be found at adrenal glands?
Adrenal context and adrenal medulla
Are the two adrenal glands connected in their work or do they act separately?
Work separately
Where do you find the kidney?
At the ribcage
What is at the upper abdomen according to the endocrine glands?
Stomach/pancreatic islets
What is at the lower abdomen according to the endocrine glands?
Ovaries and testes
What is at the small intestines according to the endocrine glands?
Duodenum and jejunum
what is the function of hypothalamus?
- control pituitary hormone release
- Interface between in and outside of body and endocrine response
What are the hormones that is linked to the hypothalamus?
- Corticotrophin releasing hormone
- Thyrotropin releasing hormone
- Somatostatin
- GnRH
- Growth releasing hormone
- Prolactin releasing hormone
- Prolactin inhibiting hormone
What is the function of the anterior pituitary?
- Controls activity of other endocrine glands
- Ovulation and pregnancy
- Sperm production
- Growth
What are the hormones linked to the anterior pituitary?
- Thyrotropin stimulating hormone
- Adrenocorticotrophic hormone
- Luteinising hormone
- Follicle stimulating hormone
- Growth hormone
- Prolactin
What is the function of the posterior pituitary?
- Regulates overall water balance
- Uterine contraction
- Ejection of milk
What are the hormone linked to posterior pituitary?
Antidiuretic hormone
What are the four types of transmembrane signalling mechanisms?
- Ligand-gated ion channel
- G-protein coupled receptors
- Enzyme-linked receptors
- Intracellular receptor
What is an example of ligand-gated ion channel?
Cholinergic nicotinic receptors
What does a ligand-gated ion channel do?
Changes in membrane potential/ion conc. in cells
What is an example of G-protein coupled receptors?
a and B adreniceptors
What does a G-protein could receptor do?
Protein phosphorylation
What is an example of enzyme-linked receptor?
Insulin receptors
What does an enzyme-linked receptor do?
Protein and receptors phosphoralisation
What is an example of intracellular receptors?
Steroid receptors
What does an intracellular receptor do?
Protein phosphoralisation and gene expression altered
What hormones is linked to the thyroid gland?
Thyroxine and thriiodothyrine (thyroid hormones)
What type of cell signalling is the hormone thyroid related to?
Intracellular receptor-thyroid-response element
What hormones is linked to the adrenal medulla?
Adrenaline and noradrenaline
What is the type of cell signalling linked to the hormones adrenalin and noradrenalin?
Adrenergic receptor (GCPR) and second messenger cAMP
What hormones is linked to adrenal cortex?
Glucocorticoids and mineralocorticoids
What hormones is linked to the pancreases?
Insulin, glucagon and somatostatin
What type of cell signalling is linked to the hormones insulin, glucagon and somatostatin?
Reception tyrosine kinase, PI3K pathway
Where is the thyroid gland located?
Neck, over trache below larynx
What is the thyroid gland made out of?
Two lobes of endocrine tissue joined together by isthmus
Where are the hormone secretion cells arranged?
In hollow spheres called follicles
What are the abbreviations for the thyroid hormones?
T4 = Thyroxine T3 = Triidothyromine
What are the thyroid hormones made out of?
Amino acid tyrosine and iodine
Where does the synthesis of the hormone take place?
thyroid follicles
Where is the thyroglobulin produced?
ER-golgi complexes
What is thyroglobulin?
Protein containing tyrosine
Where are the iodine molecules added to the thyroglobulin?
Inside the colloid region of follicles
What is the addition of iodine to thyroglobulin catalysed by?
TPO (Thyroperoxidase)
What is hypothyroidism?
less than normal levels of thyroid hormones
What can hypothyroidism cause?
- Goitre
- Enlarged glands
How is hypothyroidism caused?
- Iodine deficiency
- Ingestion of goitrogens
- Reduced production of T3 and T4
What is hyperthyroidism?
More than normal levels of thyroid hormones
What can hyperthyroidism cause?
- Goitre
- Enlarged glands
How is hyperthyroidism caused?
- Graves’ disease which produces antibodies that mimic the effects of TSH
- Overproduction of T3 and T4
What is the function of a thyroid gland?
- Increasing metabolic rate and heat production
- Sympathomimetic effect
- Effect on cardiovascular system
- Effect on growth and nervous system
What is another name for the adrenal glands?
Suprarenal Glands
Where are the two adrenal glands located?
One above each kidney and embedded in a capsule of fat
What are the two functional different regions of the adrenal glands?
- Adrenal cortex
- Adrenal medulla
What hormones are related to the adrenal cortex?
Steroid hormones (cortisol, aldosterone and androgens)
What hormones are related to the adrenal medulla?
Catecholamines (adrenaline and noradrenaline)
How many types of secretion cells do the adrenal medulla have?
2
How much adrenaline is produced from the adrenal medulla compared to noradrenaline?
75 to 80%
What is adrenal medulla part of?
Modified part of the sympathetic nervous systme
What is the adrenal medulla consist of?
Modified postganglionic sympathetic neurones called chromaffin cells
What are chromaffin cells?
Postganglionic sympathetic neurones
What do adrenalin and noradrenaline hormones act as?
Neurotransmitters
What receptors do adrenalin and noradrenalin bind to?
Adrenergic receptors
What class of cell signalising receptors are adrenergic receptors?
GPCR
What are the two major classification can adrenergic receptors be put into?
alpha and beta
What are the subclassifications of adrenergic receptors?
a1 = IP3 -Ca^2+ a2 = inhibits cAMP
B1/B2 = cAMP
What are the functions of adrenalin and noradrenaline?
Exert similar effects on many tissues and related to stress response
What do the type of effects of adrenalin and noradrenaline depend on?
Which adrenergic receptor bound to
What does the activation of a1 do?
- Excitatory response
- Contraction of blood vessels
What does the activation of a2 do?
- Inhibitory response
- Decreased smooth muscle contraction of digestive system
What does the activation of B1 do?
- Excitatory response only in heart cells
- Increase rate of heart contractions
What does the activation of B2 do?
- Inhibitory response
- Relaxation of smooth muscle cells in arteries and bronchoilies
What is the function of the pancreas?
Blood glucose levels
What are the hormones linked to the pancreases?
- Insulin
- Glucagon
What happens with blood glucose rises?
- B cells increase insulin
- a cells decrease glucagon
- Therefore decreasing glucose levels
What is glycogenesis?
Production of glycogen
Where is glycogen stored?
In muscles and liver
What is lipogenesis?
Glucose converted into fat
Where is the converted fat from glucose stored?
In fat muscle
What does protein synthesis do to excess glucose?
Converts glucose to protein
What does the insertion of GLUT-4 transports do when stimulated by insulin?
- Glycogenesis
- Lipogenesis
- Protein synthesis
What do GLUT-4 transports do?
Facilitated glucose uptake
Describe insulin cell signalling:
- Insulin receptor binds to insulin
- Phoshoration of IRS-1 protein
- IRS-1 recruitments of GRB2 activating Ras pathway
- IRS-1 activating PI-3 kinases to catalyse addition of phosphate group PIP2 converting PIP2 to PIP3
- PIP 3 binds a protein kinase called Akt (activated by other protein kinase)
- Akt activated phosphorylation key proteins increasing in glucagon synthesis activity and recruitment of GLUT-4
- GLUT-4 binds to glucose and brings inside cell
