Chem of drugs: Love chemistry
3 stages in love: attraction, passion, attachment
Many chemicals during these 3 stages. Dopamine, serotonin, etc.
- Involves pheromones: “a substance that is produced by an organism and elicits a specific
unlearned response in another member of the same species”. Mostly for insects. Usually
emitted by the female to attract the male. Male antennae are much more developed.
- Disparlure (a chemical) emitted by female moths.
- Cockroach periplanone B is the most powerful. Detected at distances up to 4km.
- Anti-pheromone: methyl salicylate by white-winged rapeseed butterfly. Male applies this
anti-pheromone. After the male and female have gotten together, the male will apply this
to mark her to fend off other males.
- Pheromones are very specific.
- Two insects can have the same pheromone, which can be a problem. The female of one
species may attract males from other species. They get stuck because their genitals are
- Dogs have great sense of smell because that’s what receives the pheromones.
- Masking agents to block smell of pheromone
- Methylparaben is a pheromone for dogs but is also used as preservatives in cosmetics.
- Female pigs are better at finding truffles than male pigs.
o Chemical emitted by male pig called androstenol in its breath is very similar to
smell of truffle.
o Androstenol ued for artificial insemination.
o Androstenol also present in men’s sweat (humans)
o Androstenol fragrance is said to be “musky”
o Women are attracted to androstenol but tends to make men fearful.
- “Women’s Dorm Syndrome” : fragrance can have a physiological effect on women.
Women who live close to each other tend to synchronize their menstrual cycle.
- Women exposed to male armpit secretion become calmer and more relaxed….
o Androstadienone? (emitted by men to affect women)
o Estratetraenol? (emitted by women to affect men)
o Seems that chemicals emitted by men have more effect on women..
Phenylethylamine (PEA) belongs in family of amphetamine
o In chocolate but when found in chocolate it can’t penetrate blood-brain barrier
o Phenylalanine is a precursor of PEA. In peanuts. Attachment
Oxytocin “the cuddle chemical”
o Women will produce higher levels of oxytocin when very close to offspring –
o Prairie vole is friendly and monogamous (but % species among mammals that are
monogamous is 3-5%)
Oxytocin, vasopressin, dopamine play roles
Vasopressin receptors are effective. When receptors activated, the feeling
of monogamy is much better. When deactivated, monogamy decreases;
male doesn’t feel like they have to be close to female.
o Mountain vole is promiscuous.
o DNA modification to