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**DONOTDELETE**
06-24-2001, 08:40 AM
Hey all,

I found this article while looking for ways in which pheromones could influence behavior. This is pretty extreme example of the way pheromones can influence behavior but it is interesting. So read on and let me know what you think.


Pheromones and Mammals
It\'s All In the Brain



by Maya Pines

The Mystery of Smell

A Secret Sense in the Human Nose?
Sniffing Out Social and Sexual Signals
Triggers of Innate Behavior
Pheromones and Mammals

New Imaging Techniques Show the Brain at Work

The Next Generation Of Brain Scans




Just what do the VNOs of rodents—or, perhaps, humans—respond to? Probably
pheromones, a kind of chemical signal originally studied in insects.
In dealing with mammals, however, scientists faced an entirely different
problem. Compared to insects, whose behavior is stereotyped and highly
predictable, mammals are independent, ornery, complex creatures. Their
behavior varies greatly, and its meaning is not always clear.
What scientists need is \"a behavioral assay that is really specific, that
leaves no doubt,\" explains Alan Singer of the Monell Chemical Senses
Center. A few years ago, Singer and Foteos Macrides of the Worcester
Foundation for Experimental Biology in Massachusetts did find an assay
that worked with hamsters—but the experiment would be hard to repeat with
larger mammals.
It went as follows: First the researchers anesthetized a male golden
hamster and placed it in a cage. Then they let a normal male hamster into
the same cage. The normal hamster either ignored the anesthetized stranger
or bit its ears and dragged it around the cage.
Next the researchers repeated the procedure with an anesthetized male
hamster on which they had rubbed some vaginal secretions from a female
hamster. This time the normal male hamster\'s reaction was quite different:
instead of rejecting the anesthetized male, the hamster tried to mate with
it.
Eventually Singer isolated the protein that triggered this clear-cut
response. \"Aphrodisin,\" as the researchers called it, appears to be a
carrier protein for a smaller molecule that is tightly bound to it and may
be the real pheromone. The substance seems to work through the VNO, since
male hamsters do not respond to it when their VNOs have been removed.
Many other substances have powerful effects on lower mammals, but the
pheromones involved have not been precisely identified and it is not clear
whether they activate the VNO or the main olfactory system, or both.
Humans are \"the hardest of all\" mammals to work with, Singer says. Yet
some studies suggest that humans may also respond to some chemical signals
from other people. In 1971, Martha McClintock, a researcher who is now at
the University of Chicago (she was then at Harvard University), noted that
college women who lived in the same dormitory and spent a lot of time
together gradually developed closer menstrual cycles. Though the women\'s
cycles were randomly scattered when they arrived, after a while their
timing became more synchronized.
McClintock is now doing a new study of women\'s menstrual cycles, based on
her findings from an experiment with rats. When she exposed a group of
female rats—let\'s call them the \"A\" rats—to airborne \"chemosignals\" taken
from various phases of other rats\' estrous cycles, she discovered that one
set of signals significantly shortened the A rats\' cycles, while another
set lengthened them. Now she wants to know whether the same is true for
humans—whether there are two opposing pheromones that can either delay or
advance women\'s cycles. In this study, she is focusing on the exact time
of ovulation rather than on synchrony.
The most direct scientific route to understanding pheromones and the VNO
may, once again, be through genetics. Working with sensory neurons from
the VNOs of rats, Catherine Dulac and Richard Axel found a new family of
genes that \"are likely to encode mammalian pheromone receptors,\" they
reported in 1995. Axel and Buck\'s teams also found a similar family in the
VNO\'s of mice.
Both groups estimate there must be 50 to 100 distinct genes of this kind
in VNO neurons. Since then, Buck\'s team and that of Catherine Dulac, who
is now an HHMI investigator at Harvard, have found a second family of
likely pheromone receptors in mammalian VNOs; these, too, are expected to
include about 100 genes. \"Now we have to match up pheromones and
receptors,\" Buck declares.
Once the genes for such receptors are definitively identified, it should
be relatively easy to find out whether equivalent genes exist in humans.
Scientists could then determine, once and for all, whether such genes are
expressed in the human nose. If they are, the receptors may provide a new
scientific clue to the compelling mystery of attraction between men and
women—some evidence of real, measurable sexual chemistry.

If your curios and want to read the full article (I deleted some of the intro) the post that is identical to this one [a mistake] is unedited

(Edited by mike at 3:46 am on April 29, 2001)

**DONOTDELETE**
07-06-2001, 09:59 PM
Genetics is at the heart of the whole issue, those that discover all the genes for pheromones and other assoicated bio chemicals, will make a fortune as the discover of androstenone found out, has anyone on the forum got any more information on the genetic research on this side of things