Release pheromones

Most female moths release sex pheromones in a typical calling behavior in which the pheromone gland is extruded to release pheromone during a particular time of the photoperiod. In most cases pheromone biosynthesis coincides... 

The queen is usually reproductively dominant within the colony and uses chemical cues as both primer and releaser pheromones to suppress the production or fecundity of other sexuals, inhibit reproduction by worker castes, modulate reproductive behaviors (e.g., inhibit swarming and orient swarms), attract males, regulate worker tasks and worker ontogeny, and produce host repellents in slave-making species. Considering the importance of queen semiochemicals in social hymenoptera, few queen pheromones have been chemically identified. The queens of most social hymenopteran colonies are attractive to workers, allowing them to be properly tended as well as to facilitate the dissemination of other pheromone cues. However, the retinue pheromone has been chemically identified in very few species. In the 1980s, queen pheromone components were identified in the fire ant, Solenopsis invicta [91,92], and in the Pharaoh s ant, Monomoriumpharaonis [93]. 

Pheromones have been classified as a function of their effect. Those triggering immediate behavioral effects were termed releasing pheromones, while those altering slower processes of physiological or developmental nature were termed priming pheromones (Wilson and Bossert 1963). The rabbit MP has a clear releasing function but recent data also show that it has another function that cannot be termed priming in the classical sense. 

In conclusion, the reliable, functionally vital and stereotyped nature of the pups response to the chemical signal governing nipple-search behaviour would seem to qualify this as a true mammalian releasing pheromone (Beauchamp, Doty, Moulton and Mugford 1976) and particularly as it appears to be species-specific rabbit pups fail to respond to lactating cats, rats, guinea pigs or even hares with nipple-search behaviour or nipple attachment (Muller 1978 Hudson 1985 own observations). 

The male released pheromone of Osmoderma eremita is (R)-5-hexyloxacy-clopentan-2-one 68 [139] (Scheme 7). In contrast, in other scarab species, pheromones are mostly produced by females. 

While the unbranched 204-207 clearly originate from the acetate pool, the structure of ( )-3,7-dimethyl-2-octene-l,8-dioic acid, callosobruchusic acid 207, a female produced copulation releasing pheromone of the azuki bean weevil, Callosobruchus chinensis [374] points to a terpenoid structure. The synthetic enantiomers [375] proved to be equally effective in releasing copulation behaviour in males. 

Pheromones are divided into four classes. The first is releaser pheromones. These generate immediate and, for the most part, behavioral responses. The silkworm moth and brown algae molecules fall into this class. In both cases, the pheromone elicits an immediate behavioral response in the recipient movement toward a female silkworm moth by the male moth in one case and movement of a male gamete toward a female gamete in the second. Sex attractants are typical releaser pheromones. 

Moving a step up the evolutionary ladder from bacteria, we encounter A/tomycei, a water mold. This mold occupies a variety of moist niches in nature on plant or animal debris along the edges of ponds, in ditches, or other wet sites. Sexual reproduction in Allomyces provides an interesting story of a releaser pheromone. Here is what happens. 

Not all releaser pheromones are sex attractants. One alternative example of a releaser pheromone is the sending out of an alarm message, warning other members of the species that some threat is at hand. The California sea anemone Anthopleura elegantissima provides a neat example of alarm signaling. 

In contrast to the evidence for primers, signalers, and modulators, there is no decent evidence to suggest that there are human releaser pheromones. That is not to argue that there are none but to state that there is no evidence for them at present. Nonetheless, products purported to be human releaser pheromones—specifically sex attractants—are widely available on the Internet. They go by such suggestive names as Scent of Eros, The Edge, Alter-ego, and Pheromone Additive. Many of these products contain either androstenone or androstenol, steroids of unknown influence on the human emotional state. 

There are four classes of pheromones. Releaser pheromones elicit immediate, behavioral responses. Primer pheromones elicit longer-term physiological or endocrine responses. Signaler pheromones act to provide information to the recipient. Modulator pheromones determine how a recipient organism will respond to a signal in a specific context. 

From our limited knowledge of spider pheromones, at least three different categories of releaser pheromones can be identified those associated with triggering courtship... 

Comparative study of releaser pheromones associated with the silk of jumping spiders (Araneae, Salticidae). New Zealand Journal of Zoology 14 1-10. 

The histidine derivatives, l-methyl-5-thiolhistidine (639) and its disulfide (640) were isolated from unfertilised eggs of the sea urchin Paracentrotus lividus [507] and from those of other echinoderms [508]. Their structures were revised after an unambiguous synthesis [509]. L-Ovothiol A disulfide (640) was also shown to be the egg release pheromone of the marine polychaete worm Platynereis dumerilii [510]. 

Zeeck E., Harder, T., Beckmann, M., and Muller, C.T., Marine gamete-release pheromones, Nature, 382, 214, 1996. 

Leal W. S., YadavaC. P. S. and Vijayvergia J. N. (1996a) Aggregation of the scarab beetle Holotrichia consanguinea in response to female-released pheromone suggests a secondary function hypothesis for semiochemical. J. Chem. Ecol. 22, 1557-1566. 

The chemical composition of the arachnid cuticle, especially the lipid layer, can be used for information transfer. These substances act as releaser pheromones and are identified by the arachnid after contact with another animal. Behavioral observations on arachnids demonstrate that chemical contact compounds are able to inhibit aggressive behavior between conspecifics (prevent cannibalism) and are used for sex recognition. The production of the cuticular compounds is sex- and age-dependent. Different studies... 

A close look at the entire apparatus revealed that the surface area of the sample chamber was in excess of 300 cm2 whereas the surface area of 15 g of glass beads, approximately the amount that would usually be in a primary collector, was only 182 cm2. When the fact that the released pheromone had to travel a distance of nearly 20 cm from the point of release to the point of entrap-... 

The release of pheromone from hollow fibers as described by Brooks (6) is dependent upon several factors including the movement of air past the open end of the fiber. In the mini-airflow apparatus the open end of the fiber is in a stream of constantly moving air so that any released pheromone is immediately swept away from the end. In the static air apparatus the only air movement across the open end will be as a result of diffusion. Consequently the concentration of pheromone is more likely to build up at the open end of a fiber in a static air apparatus than at the open end of a fiber in an airflow apparatus with the result that the release rate is lowered in the static air apparatus. Work is now in progress to evaluate the effect of air speed on release rates. 

Klassen, W. L. Rldgway, R. L. Inscoe, M. Chemical Attractants in Integrated Pest Management Programs, In "Insect Suppression Using Controlled Release Pheromone Systems", Kydonieus, A. F. and Beroza, M. Eds., CRC Press, Boca Raton, FL, In Press. 

Field measurements of concentrations of disparlure in air under woodland plots treated with three different slow release formulations showed that all released pheromone for about one month concentrations decreased about 80 in the first five days and 90-98 over 35 days. Between 75 and 85 of the disparlure remained in the formulations after 35 days even though release had became very slow. Measurements with other formulations containing tetradecenol formate applied to corn showed these were more efficient but not persistent enough to control Heliothis Zea for more than one month. No satisfactory measurements of concentrations in vapor plumes from point sources were possible even though these may be as effective as broadcasts. Further field research is limited by sampling and analysis techniques and the need for better micrometeorological data. 

The pheromone release rate is insignificant at temperatures below 10 C. Dispensers exposed inside traps in the first part of May collected beetles during a two-month period, showing that they were releasing pheromones during the beetles main flight period. 

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