The summated receptor potential was recorded from the vomeronasal organ (VNO) and olfactory epithelium (OE) of 49 human subjects of both sexes (18 to 55 years old) using surface non-polarizable silver-silver chloride electrodes. (more…)
When the term “pheromone” was defined in the late 1950s by insect researchers Peter Karlson and Martin Lüscher, it carried three main implications: that it was a message to which only members of the same species would respond; that it was a single, identifiable chemical; and that it had a definite behavioral or physiological effect on the recipient.
That definition has not held up well over time. Even in insects, each of the criteria has been violated by substances that most researchers are still willing to call pheromones. For vertebrates, the definition has been progressively loosened to the point that researchers are now heatedly debating the meaning of the term. Scientists now suggest there are four kinds of human pheromones–primers, releasers, modulators and “signalers” that provide information to the recipient without directly altering behavior. (more…)
At the present, the number of studies available on human pheromones and their role in human reproduction is very limited. Active research is being conducted on this fascinating field. With our improved understanding of the role of pheromones and its role in reproduction, gender specific pheromones isolated from men and women could be used as fertility agents for couples who wish to conceive. It might even be manipulated to work as a contraceptive. Some researchers suggest that pheromones could also be used in mood regulation, and help alleviate stress and depression.
The prostate gland in the male is a highly hormone dependent gland. Sexual activity plays a crucial role in determining the prostate cancer risk. Another hypothesis is that specific human pheromone products can be designed to modulate sexual activity, more specifically prostate gland activity in such way that it is associated with reduced risk of developing prostate caner.
Ants have it! Dogs use it to attract their mate and defend their territory. It is what drives the male moth situated miles away from the female moth to reciprocate and respond to the mating invitation. It is what makes you instantaneously get attracted to the woman or man of your dreams. Still seems fishy? ‘It’ is nothing other than the wonder chemical, pheromones, at work. Someone rightly said that ‘love is a matter of chemistry’. We now know that this is indeed true.
The study of pheromones represents one of the most fascinating areas of reproductive biology. The term pheromone is used to refer to any chemical substance produced by a living organism, that triggers a change in the sexual behavior of another organism, of the same species, but of the opposite sex.
Although the presence of pheromones has been identified as early as 1956, it was not until 1986 that the presence of these chemicals in underarms of human beings was documented. The credit for this co-discovery goes to Dr. Winifred Cutler, a leading biologist and George Preti, a chemist. Their studies published in the prestigious journal ‘Hormones and behavior’, for the first time highlighted the definite presence of human pheromones. They co-discovered these odorless yet ‘important’ chemicals after removal of sweat from human underarms.
It was also found that pheromones were gender specific. A human pheromone can influence sexual behavior in humans only. So now you know that Jim Carrey’s attraction to even animals, in the movie ‘The Animal’ was truly dramatic. It is appropriate to remember at this juncture the earlier studies of Dr. Winifred Cutler, conducted during the 1970s documented that women who have sporadic sex are less likely to have regular menstrual cycles compared to those who had regular sex with men. (more…)
There are different types of pheromones. Territorial pheromones help in defining the territory of a particular organism. For example, dogs deposit the so-called pheromones, present in their urine on specific landmarks to mark the perimeter of the claimed territory.Ever wondered about how organized and well-disciplined ants move along? Trail pheromones, secreted by ants (hydrocarbons) enable these social insects to return to their nest with food and also serve as a guide for other ants.
Alarm pheromones, as the name suggests send SOS signals to other members of the same species. Such compounds are released when a specific organism is being attacked by a predator, leading to trigger of either a fright or flight response. Surprisingly, plants have also been known to emit these compounds, when being preyed upon. This leads to production of tannins by adjacent plants, compounds that make the plant less edible for the preying organism.
Perhaps the most studied of the pheromones are sex pheromones that greatly influence the sexual behavior of an animal. These sex pheromones perform several functions ranging from sending signals about availability of a partner for mating to detecting a potential mate. Certain male organisms also release pheromones that communicate information about their species and genetic constitution. The presence of sex pheromones in animals as diverse as moths, mice and monkeys have been well documented.
Aggregation pheromones is the collective term given to chemical substances produced by one or other sex of a particular species, that attract individuals of both sexes. An unclassified set of pheromones (bees and other mammals) also exists, about which active research is being conducted at the moment.
Of special interest are the human pheromones, which are claimed to enhance the libido (sex drive) of an individual. Several companies even market human pheromones, believed to possess aphrodisiac properties. The number of studies available on human pheromones is however very limited.
By: THUY TRAN
Love is in the air … or is it pheromones?
Scientist Ariel Fenster spoke Tuesday night at the Chemistry of Love seminar to explain the chemistry behind love, sex, attachment and Viagra.
Fenster is a chemistry professor at the McGill University in Canada and has given over 600 lectures to over 370,000 people about various topics including forensic science and the chemistry of food. He has been an avid promoter of science for nearly three decades…
A case study of how scientists in the Pacific Northwest controlled an outbreak of moths in poplar trees. Transcript of radio broadcast:
19 February 2008
Back in the year two thousand, big producers of poplar trees in the American Pacific Northwest needed help. Their hybrid poplars, nearly ten years old, were under threat. Young insects were getting into the heartwood, weakening a tree and making it likely to break and fall. Small, newly planted trees were being killed.
Two professors from Washington State University discovered that the threat was not from traditional poplar pests but from a new one.
Doug Walsh and John Brown found ninety-five western poplar clearwing moths in traps in a four-week period in two thousand one. Then, during a four-week period in two thousand two, they found more than eighteen thousand moths in traps placed in the same locations…
Making the right choice when finding true love is an important business, so how do we go about selecting a mate?
Many factors add up to make us desirable to potential partners. There’s the obvious stuff like symmetrical features and good skin – which showcase a healthy development, immune system and good genes. Women look for tall men with masculine faces, kindness, wealth and status. Men prefer young, fertile women with a low waist-to-hip ratio and who are not too tall. Neither sex is very keen on people who wear glasses.
Beauty can come at a price however.
Other factors are less obvious. Research suggests that humans are attracted to partners who resemble themselves and – slightly disconcertingly – their parents too. Smell appears to be important as well; people are often more attracted to the smell of those who have different combinations of some immune system (MHC) genes to themselves. Mates with dissimilar MHC genes produce healthier offspring that are better able to thwart disease. People with similar MHC genes even prefer the same perfumes…
ScienceDaily (Jun. 21, 2007) — The coming summer vibrates with expressions of insect love and desire. The cicada’s songs or the butterflies’ bright colours are examples of how an emitting sex attracts conspecific members of the responding sex. Moth odours (pheromones), though less conspicuous for us humans, are also signals by which females guide males towards them, even on the darkest nights. Such mating recognition systems tend to be very specific, hence they are thought to play a major role in the evolution of mating barriers and in the formation of new species.
The fact that conspecific males and females recognize each other by their common use of a highly specific “language” is likely to decrease the fitness of mutants that might use slightly different signals. Such “atypical” individuals would either – and most probably – die without leaving any offspring, or – in the unlikely event that they find a mutant partner – they might found a new line that may eventually become a new species. As such, the offspring of such parents would inherit the mutant communication system of their parents, which could “spark” the divergence leading to the formation of a new species.
It is Valentine’s Day, yet again! It is that yearly phase when the air is charged with the aroma of roses. Even as we usher in this ‘Lover’s day’, lets take a peek at the facts that make it special.
Legends are aplenty on the origin(s) of Valentine’s Day. One theory asserts that Valentine was a young priest devoted to uniting distanced lovers. Another belief describes Valentine as a victim of tragic love, who signed his love letter, ‘From your Valentine’! This was the first recorded valentine card, and the phrase is put to good use even today. The validity of these stories is shrouded in mystery, but the young priest’s romantic bravado carried an universal appeal that continues to charm lovers even today!
Many claim that love cannot be confined to a calendar date. Love, for these claimants, flows freely in bountiful supply! Others, however, argue that there is a need to dedicate a day to pamper ‘that special someone’ exclusively. Valentine’s day, which is an integrated part of the European tradition, has caused youthful hearts to throb in many an Asian metro. In India, adolescent boys and girls step beyond their monetary means in an effort to woo and to win. Some of them choose this day to mollify a miffed sweetheart. Passion is engulfed by consumerism as pricey gifts are exchanged. Many young lovers suffer from ‘a -hole-in-the- wallet’ syndrome, which often takes days to recover!
There are ‘wet blankets’ too doing the rounds to douse the flames of youthful vigor. The ‘moral police’ work overtime to curb the pheromone spill in public places. Although bawdiness is not welcome in a civil society, it is important not to infringe upon a person’s right to express his/her feelings, as long as it is consensual and not a public eye sore.
‘Love and Let Others Love’ should be the punch line for this year’s Valentine’s Day. For after all it would be apt to remember that, ‘To Love is to Live’!
Source-Medindia
Dr. REEJA THARU/M
Society for the Study of Reproduction, Inc.
George Preti, Charles J. Wysocki, Kurt T. Barnhart, Steven J. Sondheimer, and James J. Leyden
Human underarm secretions, when applied to women recipients, alter the length and timing of the menstrual cycle. These effects are thought to arise from exposure to primer pheromones that are produced in the underarm. Pheromones can affect endocrine (primer) or behavioral (releaser) responses, provide information (signaler), or perhaps even modify emotion or mood (modulator).
In this study, we extracted underarm secretions from pads worn by men and placed the extract under the nose of women volunteers while monitoring serum LH and emotion/mood. Pulses of LH are excellent indicators of the release of GnRH from the brain’s hypothalamus. In women, the positive influence of GnRH on LH affects the length and timing of the menstrual cycle, which, in turn, affects fertility. Here we show that extracts of male axillary secretions have a direct effect upon LH-pulsing and mood of women. In our subjects, the putative male pheromone(s) advanced the onset of the next peak of LH after its application, reduced tension, and increased relaxation.
These results demonstrate that male axillary secretions contain one or more constituents that act as primer and modulator pheromones.
Full Text: http://www.biolreprod.org/cgi/content/full/68/6/2107
(Lake Worth, Fla.) — A study from two researchers in New Zealand theorized that a mother’s stress, mood disorders, or divorce may be related to their daughters’ earlier puberty. When they looked at 87 girls and their mothers, 67 of whom had mood disorders, their theory seemed sound.
While the study, which appears in the March/April issue of the journal Child Development, shows a correlation between mothers with mood disorders and their daughters’ earlier puberty, Bruce J. Ellis, PhD, one of the researchers, says that a direct cause and effect relationship cannot be shown.
“Both marital and family dysfunction and early pubertal timing in daughters may be caused by common underlying genetic factors,” he tells WebMD. Ellis is a lecturer in psychology at the University of Canterbury in New Zealand.
Breast Chemical: Sexual Desire Secret?
Breastfeeding mothers and their babies produce a chemical that can boost other women’s sexual desire, new research shows.
It’s a natural phenomenon found in animals — the production of chemicals called pheromones that regulate all sorts of reproductive behaviors and processes in other females, and possibly sexual desire, writes researcher Natasha A. Spencer, PhD, with The Institute for Mind and Biology at The University of Chicago.
The presence of women who are breastfeeding may be a signal to fertile women that they, too, support the demands of pregnancy and lactation, writes the author.
In a previous study, Spencer and colleagues reported that fertile women were dramatically affected — specifically a women’s period and the timing of ovulation was changed when exposed to these pheromones, she says.
But what about the women’s sexual desire and fantasies — the true measures of their motivation for sex? Will her partner benefit from her lust? If she has no partner, will she conjure up one through fantasy? That’s what Spencer’s study checked out.
Pheromones Trigger Sex Drive, Fantasies
In their study, Spencer and her research group collected the natural “breastfeeding compounds” from 26 mothers who wore pads in their nursing bras, where the saliva from their infants plus their own perspiration and milk was collected. They also wore underarm pads to collect perspiration.
The breastfeeding pads were then cut into pieces and frozen.
Then, 90 women between ages 18 and 35 — none of whom had given birth — were assigned to either the breastfeeding pads or a placebo pads group. They were asked to swipe the pads under their noses in the morning, at night, and when they wiped their upper lips, showered, or exercised during the day.
The women also tracked their lust; those with a sexual partner rated their sexual desire; they also recorded their sexual activity. Those without sexual partner recorded their moods and whether they had any sexual fantasies.
After two months of smelling pheromones from the breastfeeding mothers, women with regular partners showed a 24% increase in sexual desire, and women without partners had a 17% increase in sexual fantasies, she reports.
Among women who got placebo pads, those with partners had a slight decrease in sexual desire. Women without partners had a 28% decrease in fantasies.
“The effect became striking during the last half of the menstrual cycle after ovulation, when sexual [desire] normally declines,” says co-researcher Martha McClintock, PhD, a Distinguished Service Professor in Psychology at The University of Chicago, in a news release.
The phenomenon likely evolved in early primitive societies, when women produced children during times when food was plentiful. The pheromones would have been a way of encouraging other women to reproduce during this plentiful time.
In 1998, McClintock and her colleagues produced the first evidence of human pheromones. However, more research is needed to determine if the breastfeeding chemicals are indeed pheromones that trigger sexual desire, she adds.
Their paper on sexual desire appears in this month’s issue of the journal Hormones and Behavior.
Pheromones, those mysterious, scentless chemicals that some say drive human sexual behavior, have been studied for decades. But now researchers say they’ve finally found proof that mammals — such as humans and mice — are actually programmed to detect and use them.
A new study, published in the Sept. 5 issue of the journal Nature, shows the first real evidence that the nervous system of mice is wired to detect pheromones. And when that wiring is tampered with, their mating behavior is disrupted.
Researchers say mice contain pheromone receptors in a specialized organ in the smelling system of the body.
In their study, researchers at The Rockefeller University and the University of Maryland found that when these pheromone receptors were turned off through genetic mutation, the mice developed normally but were different in terms of aggression and sexual activity. The study authors say these differences might yield clues about pheromones’ role in influencing sexual behavior and species development.
For example, nursing female mice are normally aggressive toward other mice that invade their nest. But nursing mice without the pheromone receptors were less aggressive and slower to attack invaders.
Among male mice, researchers found several differences between the normal and genetically altered mice.
Sometimes, young, socially inexperienced mice exhibit sexual behavior toward other males until they learn to distinguish males from females. But the mutant males made fewer sexual advances toward males. Researchers say this could indicate that either the mutants are better at distinguishing between the sexes at an early age, or their overall sexual drive is reduced without the ability to detect pheromones.
In addition, mutant male mice tended to mount female mice fewer times than would otherwise be expected.
According to the authors, the existence of a functioning specialized pheromone organ in humans has been widely debated, and the role of pheromones in human behavior has yet to be clearly understood.
But since a functional role for this organ has now been shown in mice through genetic manipulation, they say the findings should stimulate more research into the counterparts of these genes in humans.
A pheromone is a chemical that triggers a natural behavioral response in another member of the same species. There are alarm pheromones, food trail pheromones, sex pheromones, and many others that affect behavior or physiology.
