Neural Communication

Ramon y Cajal Nobel Prize in Medicine 1906 Sketch of retina (1900)

The Nerve Impulse

Neural Communication

Otto Loewi Nobel Prize in 1936 Forced to leave Germany in 1938 Became US citizen in 1941 Worked at Woods Hole Institute Name pronounced as “low”

Loewi’s Experiment KW 5-2

The first known neurotransmitter acetylcholine first neurotransmitter identified (by Otto Loewi, 1921) Movement: causes muscles to contract Memory: dies in Alzheimer’s disease

Autonomic NT’s KW 5-17

Ach Pathways KW 5-19

Synapse structures KW 5-4

Steps KW 5-5

Step 1

ACh Synthesis Acetylcholine Bonded to form

Step 2

Step 3

Step 4

Step 5

Step 6

Modifying Neural Messages drug agonists - enhance potency of neurotransmitter drug antagonists - reduce effectiveness

Agonist and Antagonists Neurotransmitter molecule Receiving cell membrane Receptor site on receiving neuron Agonist mimics neurotransmitter Antagonist blocks neurotransmitter

Pain Killers Endorphins natural opiates natural key Morphine Opium poppy Agonist Naloxone Antagonist

Agonist and antagonist

Step 7

Reuptake and breakdown

AChE

Ach and AChE KW 5-11

NT characteristics KW 5-9

the catecholamines: –Dopamine found at substantia nigra and limbic system regulates emotion & movement –Norepinephrine found in brain stem and subcortex regulates emotion, reward, sleep, mood –Epinephrine Found adrenal glands may help regulate blood pressure Monoamine Neurotransmitters

Catecholamine synthesis KW 5-12

Catecholamines

Catecholamine Pathways KW 5-19

Neural Communication Dopamine pathways

Serotonin –found in raphe nuclei in brain stem –regulates temperature, sensory perception and sleep onset –LSD and antidepressants affect serotonin (antidepressants particularly affect serotonin reuptake) Monoamine Neurotransmitters

Serotonin

Serotonin Pathways KW 5-19

Neural Communication Serotonin pathways

Drug Effects

Classes of NT