1. 1 Chemical Messengers zNeurotransmitters zHormones zNeurohormones

2. 2 Types of Neurotransmitters zAcetylcholine zSerotonin zNorepinephrine zDopamine zEndorphins zGABA zGlutamate

3. 3 Acetylcholine zFound in neuromuscular junction zInvolved in muscle movements

4. 4 Disruption of Acetylcholine Functioning zCurare - blocks ACh receptors yparalysis results zNerve gases and Black Widow spider venom - too much ACh leads to severe muscle spasms and possible death

5. 5 Disruptions in ACh Functioning zCigarettes - nicotine works on ACh receptors ycan artificially stimulate skeletal muscles, leading to slight, trembling movements

6. 6 Alzheimer’s Disease zDeterioration of memory, reasoning and language skills zSymptoms may be due to loss of ACh neurons

7. 7 Serotonin zInvolved in sleep zInvolved in depression yProzac works by keeping serotonin in the synapse longer, giving it more time to exert an effect

8. 8 Norepinephrine zArousal z“Fight or flight” response

9. 9 Dopamine zInvolved in movement, attention and learning zDopamine imbalance also involved in schizophrenia zLoss of dopamine- producing neurons is cause of Parkinson’s Disease

10. 10 Parkinson’s Disease zResults from loss of dopamine-producing neurons in the substantia nigra zSymptoms include: ydifficulty starting and stopping voluntary movements ytremors at rest ystooped posture yrigidity ypoor balance

11. 11 Parkinson’s Disease zTreatments: yL-dopa ytransplants of fetal dopamine- producing substantia nigra cells yadrenal gland transplants yelectrical stimulation of the thalamus to stop tremors

12. 12 Endorphins zControl pain and pleasure zReleased in response to pain zMorphine and codeine work on endorphin receptors Involved in healing effects of acupuncture

13. 13 Endorphins zRunner’s high - feeling of pleasure after a long run is due to heavy endorphin release

14. 14 Gamma-Aminobutyric Acid (GABA) zMain inhibitory neurotransmitter zBenzodiazepines (which include tranquilizers such as Valium) and alcohol work on GABA receptor complexes

15. 15 Huntington’s Disease zInvolves loss of neurons in striatum that utilize GABA zSymptoms: yjerky involuntary movements ymental deterioration

16. 16 Glutamate zMajor excitatory neurotransmitter zToo much glutamate (and too little GABA) associated with epileptic seizures

17. 17 Hormones zChemical messengers secreted into bloodstream Hormonal communication Endocrine cells Blood- stream Target cells

18. 18 Hormones vs. Neurotransmitters zDistance traveled between release and target sites yhormones travel longer distances yneurotransmitters - travel across a synaptic cleft (20 nm) zSpeed of communication yhormones - slower communication yneurotransmitters - rapid, specific action

19. 19 Hormones zReleased by organs, including the stomach, intestines, kidneys and the brain zAlso released by a set of glands called the endocrine system

20. 20 Endocrine System zConsists of hormone-releasing glands zIncludes: y hypothalamus y pituitary gland y adrenal glands y thyroid gland y parathyroid glands y pineal gland y pancreas y ovaries and testes

21. 21 Hypothalamus and Hormones zHypothalamus releases hormones or releasing factors which in turn cause pituitary gland to release its hormones

22. 22 Pituitary Gland z“Master endocrine gland” zProduces hormones that control hormone production in other endocrine glands

23. 23 Pituitary Gland zAlso produces growth hormones zToo little pituitary activity produces dwarfism zToo much leads to gigantism

24. 24 Pituitary Gland zAlso involved in breastfeeding zProduces prolactin ystimulates milk production zProduces oxytocin yinvolved in milk release

25. 25 Adrenal Glands zInvolved in stress response zHormones released include: yepinephrine (a.k.a. adrenaline) ynorepinephrine (a.k.a. noradrenaline) 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 zThyroid gland - metabolism zPineal gland - sleep and wakefulness zPancreas - regulates blood sugar level zOvaries and testes - secrete sex hormones such as testosterone and estrogen