Chemical

914 views

Published on

Published in: Health & Medicine
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
914
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
0
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Chemical

  1. 1. Chemical Messengers <ul><li>Neurotransmitters </li></ul><ul><li>Hormones </li></ul><ul><li>Neurohormones </li></ul>
  2. 2. Types of Neurotransmitters <ul><li>Acetylcholine </li></ul><ul><li>Serotonin </li></ul><ul><li>Norepinephrine </li></ul><ul><li>Dopamine </li></ul><ul><li>Endorphins </li></ul><ul><li>GABA </li></ul><ul><li>Glutamate </li></ul>
  3. 3. Acetylcholine <ul><li>Found in neuromuscular junction </li></ul><ul><li>Involved in muscle movements </li></ul>
  4. 4. Disruption of Acetylcholine Functioning <ul><li>Curare - blocks ACh receptors </li></ul><ul><ul><li>paralysis results </li></ul></ul><ul><li>Nerve gases and Black Widow spider venom - too much ACh leads to severe muscle spasms and possible death </li></ul>
  5. 5. Disruptions in ACh Functioning <ul><li>Cigarettes - nicotine works on ACh receptors </li></ul><ul><ul><li>can artificially stimulate skeletal muscles, leading to slight, trembling movements </li></ul></ul>
  6. 6. Alzheimer’s Disease <ul><li>Deterioration of memory, reasoning and language skills </li></ul><ul><li>Symptoms may be due to loss of ACh neurons </li></ul>
  7. 7. Serotonin <ul><li>Involved in sleep </li></ul><ul><li>Involved in depression </li></ul><ul><ul><li>Prozac works by keeping serotonin in the synapse longer, giving it more time to exert an effect </li></ul></ul>
  8. 8. Norepinephrine <ul><li>Arousal </li></ul><ul><li>“ Fight or flight” response </li></ul>
  9. 9. Dopamine <ul><li>Involved in movement, attention and learning </li></ul><ul><li>Dopamine imbalance also involved in schizophrenia </li></ul><ul><li>Loss of dopamine- producing neurons is cause of Parkinson’s Disease </li></ul>
  10. 10. Parkinson’s Disease <ul><li>Results from loss of dopamine-producing neurons in the substantia nigra </li></ul><ul><li>Symptoms include: </li></ul><ul><ul><li>difficulty starting and stopping voluntary movements </li></ul></ul><ul><ul><li>tremors at rest </li></ul></ul><ul><ul><li>stooped posture </li></ul></ul><ul><ul><li>rigidity </li></ul></ul><ul><ul><li>poor balance </li></ul></ul>
  11. 11. Parkinson’s Disease <ul><li>Treatments: </li></ul><ul><ul><li>L-dopa </li></ul></ul><ul><ul><li>transplants of fetal dopamine-producing substantia nigra cells </li></ul></ul><ul><ul><li>adrenal gland transplants </li></ul></ul><ul><ul><li>electrical stimulation of the thalamus to stop tremors </li></ul></ul>
  12. 12. Endorphins <ul><li>Control pain and pleasure </li></ul><ul><li>Released in response to pain </li></ul><ul><li>Morphine and codeine work on endorphin receptors Involved in healing effects of acupuncture </li></ul>
  13. 13. Endorphins <ul><li>Runner’s high - feeling of pleasure after a long run is due to heavy endorphin release </li></ul>
  14. 14. Gamma-Aminobutyric Acid (GABA) <ul><li>Main inhibitory neurotransmitter </li></ul><ul><li>Benzodiazepines (which include tranquilizers such as Valium) and alcohol work on GABA receptor complexes </li></ul>
  15. 15. Huntington’s Disease <ul><li>Involves loss of neurons in striatum that utilize GABA </li></ul><ul><li>Symptoms: </li></ul><ul><ul><li>jerky involuntary movements </li></ul></ul><ul><ul><li>mental deterioration </li></ul></ul>
  16. 16. Glutamate <ul><li>Major excitatory neurotransmitter </li></ul><ul><li>Too much glutamate (and too little GABA) associated with epileptic seizures </li></ul>
  17. 17. Hormones <ul><li>Chemical messengers secreted into bloodstream </li></ul>Hormonal communication Endocrine cells Blood- stream Target cells
  18. 18. Hormones vs. Neurotransmitters <ul><li>Distance traveled between release and target sites </li></ul><ul><ul><li>hormones travel longer distances </li></ul></ul><ul><ul><li>neurotransmitters - travel across a synaptic cleft (20 nm) </li></ul></ul><ul><li>Speed of communication </li></ul><ul><ul><li>hormones - slower communication </li></ul></ul><ul><ul><li>neurotransmitters - rapid, specific action </li></ul></ul>
  19. 19. Hormones <ul><li>Released by organs, including the stomach, intestines, kidneys and the brain </li></ul><ul><li>Also released by a set of glands called the endocrine system </li></ul>
  20. 20. Endocrine System <ul><li>Consists of hormone-releasing glands </li></ul><ul><li>Includes: </li></ul><ul><ul><li>hypothalamus </li></ul></ul><ul><ul><li>pituitary gland </li></ul></ul><ul><ul><li>adrenal glands </li></ul></ul><ul><ul><li>thyroid gland </li></ul></ul><ul><ul><li>parathyroid glands </li></ul></ul><ul><ul><li>pineal gland </li></ul></ul><ul><ul><li>pancreas </li></ul></ul><ul><ul><li>ovaries and testes </li></ul></ul>
  21. 21. Hypothalamus and Hormones <ul><li>Hypothalamus releases hormones or releasing factors which in turn cause pituitary gland to release its hormones </li></ul>
  22. 22. Pituitary Gland <ul><li>“ Master endocrine gland” </li></ul><ul><li>Produces hormones that control hormone production in other endocrine glands </li></ul>
  23. 23. Pituitary Gland <ul><li>Also produces growth hormones </li></ul><ul><li>Too little pituitary activity produces dwarfism </li></ul><ul><li>Too much leads to gigantism </li></ul>
  24. 24. Pituitary Gland <ul><li>Also involved in breastfeeding </li></ul><ul><li>Produces prolactin </li></ul><ul><ul><li>stimulates milk production </li></ul></ul><ul><li>Produces oxytocin </li></ul><ul><ul><li>involved in milk release </li></ul></ul>
  25. 25. Adrenal Glands <ul><li>Involved in stress response </li></ul><ul><li>Hormones released include: </li></ul><ul><ul><li>epinephrine (a.k.a. adrenaline) </li></ul></ul><ul><ul><li>norepinephrine (a.k.a. noradrenaline) </li></ul></ul>Shadowy figure Brain interprets stimulus as fearsome. Hypothalamus secretes corticotropin-releasing factor into blood portal path to anterior pituitary. Anterior pituitary secretes corticotropin, carried by blood to the adrenal gland. Adrenal secretes cortisol and other hormones. The adrenal hormones act on various tissues to enable adaptation to stress.
  26. 26. Endocrine Glands <ul><li>Thyroid gland - metabolism </li></ul><ul><li>Pineal gland - sleep and wakefulness </li></ul><ul><li>Pancreas - regulates blood sugar level </li></ul><ul><li>Ovaries and testes - secrete sex hormones such as testosterone and estrogen </li></ul>

×