1. CHEMISTRY OF LOVE Presented by Nhi Quach Abstract # 23 Chem 12B Spring 2006

2. Outline: I) How do we fall in love? 1) Study on voles 2) Chemistry involved II) Names, functions and facts about those chemicals. 1) Dopamine 2) Oxytocin 3) Vasopressin 4) Endorphin

3. Study on prairie voles Why prairie vole? It’s a sociable creature, one of the only 3% of mammal species form monogamous relationships. They mate for life. When they have offspring, the couple works together to care for them. They spend hours grooming each other and just hanging out together.

4. What happened? When the prairie have sex, * dopamine is released in the brain's reward center making the experience enjoyable and ensuring that they want to do it again. * the hormones oxytocin and vasopressin are released forms a bond with its mate and make them want to have sex with the same vole only. Later on, endorphins is created to form a steadier and more stable relationship as it’s every addictive.

5. What if….? If we block dopamine, they forget to eat, drink and make love, because they don’t feel good about doing those routines. If we knock out oxytocin or vasopressin, they become unfaithful as they don’t remember the other voles they meet. If we inject these hormone, the vole falls in love with the next vole it meets.

6. How about humans? Same chemistry: Phenyl ethyl amine: make us feel good Vasopressin: recognize our loved one Oxytocin: calm and sensitive about the other Endorphin: addicted to another, form long-term relationship. Same biology Hormone receptor in reward and reinforcement region of brain.

7. Phenyl ethyl amine In human brain, it functions as a neurotransmitter (trace amine) Substituted phenethylamines are a broad and diverse class of compounds that include neurotransmitter, hormones, stimulant, antidepressants, etc. such as amphetamines, dopamine, epinephrine,

8. Dopamine supplied as a medication producing effects such as increased heart rate and blood pressure. To increase the amount of dopamine in the brains of patients with diseases such as Parkinson’s Disease and Dopa-Responsive Dystonia, a synthetic precursor to dopamine such as L-DOPA can be given, since this will cross the blood-brain barrier.

9. Dopamine (cont.) Dopamine is critical to the way the brain controls our movements Shortage of dopamine, particularly the death of dopamine neurons in the nigrostriatal, causes Parkinson’s disease, in which a person loses the mobility. Dopamine controls the flow of information. Dopamine disorders can cause a decline in neurocognitive functions, especially memory, attention and problem-solving. Dopamine is commonly associated with the pleasure system of the brain, providing feelings of enjoyment and reinforcement to motivate us to do certain activities.

10. Oxytocin Oxytocin is a hormone found in mammals that also acts as a neurotransmitter in the brain. In women, it is released mainly during labor, and after stimulation of the nipples, facilitating birth and breastfeeding. Oxytocin is released during orgasm in both sexes. In the brain, it is involved in social recognition, bonding, and formation of trust between people. Also called cuddling chemical. Oxytocin makes us calmer and more sensitive to the feelings of others.

11. Oxytocin (cont.)

12. Oxytocin has peripheral (hormonal) actions, and also has actions in the brain. It is synthesized to help women induce labor, stimulate breastfeeding. Naturally, it’s there to increase trust, love, sexual arousal, and reduce fear, stress.

13. Vasopressin Vasopressin released within the brain implicated in memory formation, including delayed reflexes, image, short- and long- term memory, though the mechanism remains unknown. Vasopressin initiates and sustains patterns of activity that support the pair-bond between the sexual partners; in particular, it seems to induce the male to become aggressive towards other males Similar structure with oxytocin.

14. Vasopressin (cont.) Decreased vasopressin release or decreased renal sensitivity to vasopressin leads to diabetes insipidus, (increased blood sodium content), polyuria (excess urine production), and polydipsia (thirst). High levels of vasopressin secretion (syndrome of inappropriate antidiuretic hormone, SIADH) and resultant hyponatremia (low blood sodium levels) occurs in brain diseases and conditions of the lungs.

15. Endorphin It’s endogenous opioid biochemical compounds. They are peptides produced by the pituitary gland and the hypothalamus in vertebrates. It’s used to produce analgesia and a sense of well-being. In other words, they might work as "natural pain killers.“ Most of other details are controversial and unclear.

16. Reference http://www.cyberparent.com/love/love- being-in-love-1.htm http://www.economist.com/printedition/displ ayStory.cfm?Story_ID=2424049 http://en.wikipedia.org/wiki/Dopamine http://en.wikipedia.org/wiki/Endorphins http://en.wikipedia.org/wiki/Oxytocin http://www.utexas.edu/research/asrec/dopa mine.html http://science.howstuffworks.com/love.htm