Receptors What!! There’s More??

Receptors are a very important part of Neurotransmission What we know….(or think we know) –The number of receptors and the ratio of inhibitory and excitatory receptors are primarily determined by genetics (from DNA), but can be influenced by stress, drugs, and other Environmental factors –NTs, hormones and drugs can all bind to receptors

There are two types of receptors we will discuss. Depending on the type AND location they perform differently. Metabolic Receptors- Activate G protein binds to receptor inside the cell Ionic Receptors-These open and close ion channels

Receptors are affected by: Full Agonists –Turn on the synthesis of the second messenger or fully open ion channel Antagonists –Block natural antagonist NT, which must be present or they do nothing Partial agonists and antagonists –Act as net Inverse Agonists –Closes ion channels or Turns off synthesis of 2 nd mes. AND Allosteric Modulation: What is this?

Neurotransmitters

The Main Six Serotonin Dopamine Norepinephrine Acetylcholine GABA Glutamate

Serotonin Regulates: Body temperature Hunger and thirst Sexual behavior Sleep & Arousal Aggression Play a role in: Mania Depression & Anxiety Schizophrenia (moderate role) OCD Food Craving & Bulimia Phobia & Panic Migraine Headaches

Dopamine Involved in –Voluntary Movement –Parkinson’s Disease and Huntington’s Chorea (moderate in HC) –Tourette’s –Mania –Depression –Schizophrenia

Norepinephrine Flight or Fight Mania Depression (esp. fatigue, apathy, concentration) Schizophrenia Panic Attacks

Acetylcholine (ACH) Parasympathetic Nervous System Regulation of Voluntary Movement Memory Associated with decline in normal aging and Alzheimer's

GABA Inhibition Sleep Hunington’s Chorea

Glutamate Learning and Memory- excitatory NTs allow messages to pass more efficiently in the hippocampus