Axillary secretions, human

Preti, G., Cutler, W.B., Garcia, C-R., Huggins, G.R. and Lawley, HJ. (1986) Human axillary secretions influence women s menstrual cycles the role of donor extract of female. Horm. Behav. 20, 474-482. 

Proteins also occur in many excretions and glandular secretions, from turtles to mice and humans. Intensive studies are clarifying their role in signaling. In axillary secretion from hrunan males, the main odoriferous acid, (E)-3-methyl-2-hexanoic acid, (E)-3M2H for short, is bound to two apocrine secretion-binding proteins (ASOBl and 2) of molecular masses 45 and 26kDa, respectively. The... 

The androst-16-enes in humans are also produced in the testes but spread widely by transport through the body in blood, saliva, seminal fluid, and axillary secretion of males (Gower, 1989). 

Numerous studies with humans have examined the perception of odors collected on T-shirts and pads from the upper part of the body and the axillae (Russell, 1976 Doty, et al., 1978 Schleidt, 1980 Schleidt, et al., 1981). These odors allow individuals to identify their own smell as well as that of their spouse and close kin (Porter Moore, 1981 Cer-noch Porter, 1985 Porter, et al., 1986 Hepper, 1988). Analytical studies of axillary secretions collected from women across the menstrual cycle suggest changes in the ratios of both the odor-producing bacteria (Reilly, et al., 1996) and odorants (Preti, et al., 1987 Reilly, et al., 1996). These studies suggest that chemical cues from the axillae contain sufficient differences in the concentration of odorants to allow for discrimination of individuals and phase in the menstrual cycle in female subjects. 

Bird, S., and Gower, D. B., 1980, Measurement of 5a-androst-16-en-3-one in human axillary secretions by radioimmunoassay, J. Endocrinol., 85 8P. 

Evidence has been accumulating that extracellular metabolic activity of microorganisms, mainly bacteria, occurs within skin glands and on the skin surface (Albone, 1997). Sterile human apocrine secretions do not develop the characteristic axillary odour (Shelley et al., 1953). In the salivary secretions of the boar, transformations of the pheromonal 16-androstene steroids 2. were attributed to the microbial flora (Booth, 1987). 

Spielman A., Sunavala G., Harmony J., Stuart W., et al. (1998). Identification and immunohistochemjcal localization of protein precursors to human axillary odors in apocrine glands and secretions. Arch Dermatol 134, 813-818. 

Axillary odour might not be the only olfactory cue to women s reproductive status. Due to the cyclic fluctuations in composition of vaginal secretion one may expect similar changes in vaginal odour. This was demonstrated thirty years ago by Doty, Ford, Preti and Huggins (1975). However, as we have suggested previously, we believe that due to bipedality the axillary odour is of higher importance in humans (Havlicek et al. 2006). 

Possible sources of semiochemicals in primates include the scalp, hair, axillary region, genitals, chest and/or breast, feet and skin. As possible starting points for studies on human semiochemicals, the constituents present in the effluvia, excretions and secretions of humans have been characterized. For example, a large number of constituents of normal human urine have been identified since modern gas chromatographic techniques became available for this type of analysis. The results of these earlier studies on human effluvia and urine have been reviewed by Albone [148]. 

Apocrine glands produce a viscous secretion that contains compounds related to communication between individuals of a species, by acting as a sex attractant or as territorial marker. In humans, these glands are located only in the axillary, pubic, and perianal region. 

In a later experiment, two pheromones from axillary odor of young women influenced the estrus cycle of other women (Stern and McClintock, 1998). Armpit secretion that appears odorless to humans was applied daily between the upper lip and nose of healthy young women and had two opposite effects depending on the menstrual phase of the odor donors. Secretion from nine donor women, collected on pads in their armpits during the follicular phase of their cycles... 

Zeng, X.-N., Leyden, J. J., Brand, J. G., etal. (1992). An investigation of human apocrine gland secretion for axillary odor precursors. JournalofChemicalEcology 18,1039-1055. 

Thus, Amoore suggests that, if we have a specific olfactory receptor for a given odorant then that odorant might be naturally given off by the body. The sweaty odor of isovaleric acid is probably part of the foot odor and is produced by the action of skin bacteria on apocrine secretion (see below). Pyrolline, the spermous odor, has been shown to be produced by enzymatic breakdown of the polyamines in semen (40). Androst-16-en-3-one, the urinous primary odor, has axillary-like odor the related androstenol, which is found in urine, is perceived as a musky odor to some individuals (41). Both steroids are found in axillary sweat and may be formed as metabolites of apocrine secretion. Chemicals which fit the malty anosmia have not as yet been reported from human odor sources. The natural musks, such as cycloheptadecenone (civet), were first obtained from animal scent glands. 

Spielman, A.I., Harmony, J.A.K., Stuart, W.D., Leyden, J.J., Sunavala, G., Turner, G., Vowels, B.R., Lam, W.C., Yang, S. Preti, G. 1998. Identification and immunohistochemical localization of protein precursors to human axillary odor in apocrine glands and secretions. Arch. Dermatol., 134, in press. 

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