Androgen metabolism by rat epididymis. Metabolic conversion of 3H 5alpha-androstane-3alpha,17beta-diol, in vitro

The epididymis of adult rats metabolizes 3H 5alpha-androstane-3alpah,17beta-diol (3alpha-diol) by experiments in vitro. After incubation of tissue slices at 37 degrees C for 2 hours, 2% of the radioactivity was found in the water-soluble fraction whereas 98% was found to be ether soluble (free steroids). Further investigation of the free steroids showed the following to be present: 3alpha-diol 39.9%, DHT (17beta-hydroxy-5alpha-androstan-3-one) 33.7%, androsterone (3alpha-hydroxy-5alpha-androstan-17-one) 9.2%, 3beta-diol (5alpha-androstane-3beta,17beta-diol) 2.6%, 5alpha-A-dione (5alpha-androstan-3,17-dione) 1.1%, delta 16-3alpha-ol (5alpha-androst-16-en-3alpha-ol) 1.0%, delta16-3beta-ol (5alpha-androst-16-en-3beta-ol) 2.6%, delta 16-3-one (5alpha-androst-16-en-3-one) 2.9%, and polar compounds 3.3%. When segments of the epididymis (caput and cauda) were incubated in the same way, qualitatively similar metabolites were formed but a greater amount of 3alpha-diol was metabolized by the cauda epididymis. This increase was mainly accounted for by an increased formation of delta 16 compounds (14.3% in cauda, 4.3% in caput). This is most probably due to the presence of larger numbers of mature spermatozoa, which, as we have previously shown, form delta16 steroids from 3alpha-diol and DHT (5).     

Studies on the biosynthesis in vivo and excretion of 16-unsaturated C19 steroids in the boar

1. In one experiment [7alpha-(3)H]pregnenolone was infused continuously for 12min into the left spermatic artery of a sexually mature boar and blood was collected during this period by continuous drainage from the spermatic vein. After infusion, the testis was removed and immediately cooled to -196 degrees C. 2. From both the testicular tissue and the spermatic venous plasma, (3)H-labelled 16-unsaturated C(19) steroids were isolated and characterized and their radiochemical purity was established. 5alpha-Androst-16-en-3alpha- and 3beta-ol occurred mainly as sulphate conjugates and to a lesser extent as free steroids. Only traces of these alcohols occurred as glucosiduronate conjugates. 5alpha-Androst-16-en-3-one was found in the free (ether-extractable) fraction. 3. The isotope concentration of each of the (3)H-labelled 16-unsaturated C(19) steroids in testicular tissue was different from that in spermatic venous plasma. 4. The ratios of tritiated 5alpha-androst-16-en-3alpha- and 3beta-ol (free steroids) to their respective sulphate conjugates in the testicular tissue were less than the ratios of the same compounds in the spermatic venous plasma. The possibility that the sulphates are partially hydrolysed by testicular sulphatases before secretion is discussed. 5. In a second experiment, a continuous close-arterial infusion of [7alpha-(3)H]pregnenolone into the left testis was performed over a 200min period and all the urine that accumulated during the infusion was collected for analysis. 6. No (3)H-labelled 16-unsaturated C(19) steroids were detected in the urine as free steroids. Only a trace of 5alpha-androst-16-en-3alpha-ol was detected conjugated as glucosiduronate, whereas the corresponding 3beta-alcohol occurred mainly as glucosiduronate and to a lesser extent as sulphate. 7. The absence of 5alpha-androst-16-en-3beta-ol glucosiduronate in the spermatic venous blood and its presence in considerable amount in the urine may be attributed to hepatic glucuronyl transferase activity.     

Zymogen secretion and phospholipid metabolism in the pancreas. Phospholipids of the zymogen granule

1. The metabolism of [4-(14)C]pregnenolone to androst-16-enes has been studied in short-term incubations of boar testis tissue. With fresh tissue androsta-5,16-dien-3beta-ol (8%) and 5alpha-androst-16-en-3beta-ol (2%) were formed. Tissue that had been stored at -20 degrees C was still capable of metabolizing pregnenolone to androsta-5,16-dien-3beta-ol. 2. NADPH was essential for the formation of androsta-5,16-dien-3beta-ol from pregnenolone; NADH had less activity and ATP was not necessary for the reaction. 3. [4-(14)C]Androsta-5,16-dien-3beta-ol, prepared biosynthetically from [4-(14)C]pregnenolone, was shown to be converted by boar testis preparations into androsta-4,16-dien-3-one (31%) if NAD(+) was present or into 5alpha-androst-16-en-3beta-ol (4%) if NADPH was present. 4. 17alpha-Hydroxyandrost-4-en-3-one and 3beta,17alpha-dihydroxypregn-5-en-20-one were considered as possible precursors for androst-16-ene formation, but both were shown to be ineffective. 5. No radioactivity was incorporated into androst-5-en-3beta-ol used to trap any corresponding (14)C-labelled compound formed from [4-(14)C]pregnenolone.     

Utilization and metabolic effects of acetaldehyde and ethanol in the perfused rat liver

1. The formation of the two 16-unsaturated alcohols 5alpha-androst-16-en-3alpha-ol and 5alpha-androst-16-en-3beta-ol from [5alpha-(3)H]5alpha-androst-16-en-3-one has been demonstrated in boar testis homogenates. 2. The optimum yield (23%) of the 3alpha-alcohol was obtained in the presence of NADPH, whereas that for the 3beta-alcohol (74%) was obtained when NADH was the added cofactor. 3. The two alcohols were not interconvertible. 4. Prolonged storage of boar testis tissue at -20 degrees C abolished the ability to form all androst-16-enes except androsta-4,16-dien-3-one from [4-(14)C]progesterone. 5. The production of 5alpha-androst-16-en-3-one and the two alcohols from [7alpha-(3)H]androsta-4,16-dien-3-one only occurred when fresh tissue was used, whereas reduction of [5alpha-(3)H]5alpha-androst-16-en-3-one was unaffected by storage of testis at -20 degrees C. 6. NADPH was the preferred cofactor for the reduction of androsta-4,16-dien-3-one. 7. The previously established conversion of androsta-5,16-dien-3beta-ol into androsta-4,16-dien-3-one was shown to be reversible, NADH and NADPH being equally effective cofactors. 8. Pathways of biosynthesis of 5alpha-androst-16-en-3alpha- and 3beta-ols, with the C(19) 3-oxo steroids as intermediates, are presented.     

Studies on anabolic steroids--4. Identification of new urinary metabolites of methenolone acetate (Primobolan) in human by gas chromatography/mass spectrometry

The metabolism of methenolone acetate (17 beta-acetoxy-1-methyl-5 alpha-androst-1-en-3-one), a synthetic anabolic steroid, has been investigated in man. After oral administration of a 50 mg dose of the steroid to two male volunteers, twelve metabolites were detected in urine either in the glucuronide, sulfate or free steroid fractions. Methenolone, the parent steroid was detected in urine until 90 h after administration. Its cumulative urinary excretion accounted for 1.63% of the ingested dose. With the exception of 3 alpha-hydroxy-1-methylen-5 alpha-androstan-17-one, the major biotransformation product of methonolone acetate, metabolites were excreted in urine at lower levels, through minor metabolic routes. Most of methenolone acetate metabolites were isolated from the glucuronic acid fraction, namely methenolone, 3 alpha-hydroxy-1-methylen-5 alpha-androstan-17-one, 3 alpha-hydroxy-1 alpha-methyl-5 alpha-androstan-17-one, 17-epimethenolone, 3 alpha,6 beta-dihydroxy-1-methylen-5 alpha-androstan-17-one, 2 xi-hydroxy-1-methylen-5 alpha-androstan-3,17-dione, 6 beta-hydroxy-1-methyl-5 alpha-androst-1-en-3,17-dione, 16 alpha-hydroxy-1-methyl-5 alpha-androst-1-en-3,17-dione and 3 alpha,16 alpha-dihydroxy-1-methyl-5 alpha-androst-1-en-17-one. Interestingly, the metabolites detected in the sulfate fraction were isomeric steroids bearing a 16 alpha- or a 16 beta-hydroxyl group, whereas 1-methyl-5 alpha-androst-1-en-3,17-dione was the sole metabolite isolated from the free steroid fraction. Steroids identity was assigned on the basis of the mass spectral features of their TMS ether, TMS enol-TMS ether, MO-TMS, and d9-TMS ether derivatives and by comparison with reference and structurally related steroids. The data indicated that methenolone acetate was metabolized into several compounds resulting from oxidation of the 17-hydroxyl group and reduction of A-ring substituents, with or without concomitant hydroxylation at the C6 and C16 positions.     

Uptake and metabolism of androgens by bovine spermatozoa

Spermatozoa from bovine ejaculates and cauda epiditymidis were incubated with either tritiated 17 beta-hydroxy-5 alpha-androstane-3-one (DHT) or 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha-diol). Examination of the medium incubations demonstrated metabolic conversion of both DHT and 3 alpha-diol when these steriods were incubated with ejaculated sperm. In addition to this interconversion, the following metabolities were identified: 5 alpha-androstane-3 beta, 17 beta-diol, (3 beta-diol), androsterone and 5 alpha-androstane-3, 17-dione (5 alpha-A-dione). Incubations with cauda spermatozoa showed similar metabolic patterns. Androgen binding was exhibited by both sperm types. Examination of the washed cauda sperm pellet, following incubations with 3 alpha-diol showed that the incubated steroid was the most abundantly bound. DHT and 5 alpha-androst-16-en-3 alpha-ol (delta 16-3 alpha-ol1 were also detected. The major part of the radioactivity bound in the sperm pellet was identified as DHT when this steroid was used as the substrate; the remaining radioactivity consisted of 3 alpha-diol and delta 16-3 alpha-ol. Investigations of ejaculated sperm pellets gave similar results apart from the additional identification of 5 alpha-androst-16-en-3 one (delta 16-3-one) and 5 alpha-androst-16-en-3 beta-ol (delta 16-3 beta-ol (delta 16-3 beta-ol).     

Studies on anabolic steroids--6. Identification of urinary metabolites of stenbolone acetate (17 beta-acetoxy-2-methyl-5 alpha-androst-1-en-3-one) in human by gas chromatography/mass spectrometry

The metabolism of stenbolone acetate (17 beta-acetoxy-2-methyl-5 alpha-androst-1-en-3-one), a synthetic anabolic steroid, has been investigated in man. Nine metabolites were detected in urine either as glucuronic or sulfuric acid aglycones after oral administration of a single 50 mg dose to a male volunteer. Stenbolone, the parent compound, was detected for more than 120 h after administration and its cumulative excretion accounted for 6.6% of the ingested dose. Most of the stenbolone acetate metabolites were isolated from the glucuronic acid fraction, namely: stenbolone, 3 alpha-hydroxy-2-methyl-5 alpha-androst-1-en- 17-one, 3 alpha-hydroxy-2 xi-methyl-5 alpha-androst-17-one; 3 isomers of 3 xi, 16 xi-dihydroxy-2-methyl-5 alpha-androst-1-en-17-one; 16 alpha and 16 beta-hydroxy-2-methyl-5 alpha-androst-1-ene-3, 17-dione; and 16 xi, 17 beta-dihydroxy-2-methyl-5 alpha-androst-1-en-3-one. Only isomeric metabolites bearing a 16 alpha or a 16 beta-hydroxyl group were detected in the sulfate fraction. Interestingly, no metabolite was detected in the unconjugated steroid fraction. The steroids identities were assigned on the basis of their TMS ether, TMS enol-TMS ether, MO-TMS and d9-TMS ether derivatives and by comparison with reference and structurally related steroids. Data indicated that stenbolone acetate was metabolized into several compounds resulting from oxidation of the 17 beta-hydroxyl group and/or reduction of A-ring delta-1 and/or 3-keto functions with or without hydroxylation at the C16 position. Finally, comparison of stenbolone acetate urinary metabolites with that of methenolone acetate shows similar biotransformation pathways for both delta-1-3-keto anabolic steroids. This indicates that the position of the methyl group at the C1 or C2 position in these steroids has little effect on their major biotransformation routes in human, to the exception that stenbolone cannot give rise to metabolites bearing a 2-methylene group since its 2-methyl group cannot isomerize into a 2-methylene function through enolization of the 3-keto group as previously observed for methenolone.     

Changes with age in the occurrence of C19 steroids in the testis and submaxillary gland of the boar.

After extraction from the testes of boars of different ages, C19 steroids including 16-androstenes were determined by gas-liquid chromatography. Similarly, 16-androstenes were determined in the submaxillary glands of these boars. A high concentration of testosterone was found in the testes of 84-day-old fetuses, and this might be significant in the differentiation of male behaviour. The amount of testosterone exceeded that of androstenedione during postnatal development, and dehydroepiandrosterone and 5-androstenediol as free and sulphates were found in high concentrations particularly in postpubertal boars, suggesting that the 5-ene pathway for the synthesis of testosterone might be important. There was a change in the predominance of individual 16-androstenes in the testis during development, which closely paralleled the sequence for the biosynthesis of these compounds proposed from previous studies in vitro. Whereas the amount of 5alpha-androst-16-en-3beta-ol exceeded that of 5alpha-androst-16-en-3alpha-ol in post-pubertal testes, 5alpha-androst-16-en-3alpha-ol was predominant in the submaxillary glands at all ages. The high concentration of 16-androstenes found in the mature boar, are discussed in relation to their release as pheromones and as factors responsible for taint in boar meat.     

Characterisation of androstenone metabolism in pig liver microsomes

Androstenone (5 alpha-androst-16-en-3-one) is a steroid pheromone produced in the testis. Excessive accumulation of androstenone together with skatole (3-methyl-indole) in the adipose tissue of some male pigs leads to "boar taint". In isolated pig hepatocytes androstenone represses the expression of cytochrome P450IIE1 (CYP2E1), the enzyme principally responsible for skatole metabolism. Androstenone can be metabolised in liver microsomes but the pathway has not been established. We have investigated androstenone metabolism in liver microsomes from two breeds of pigs exhibiting low and high levels of androstenone in adipose tissue-Large White (LW) and Meishan (M), respectively. Androstenone was reduced in isolated liver microsomes mainly to beta-androstenol using NADH as a co-factor. The rate of beta-androstenol formation in the presence of NADPH was very low. In microsomes from LW pigs the rate of beta-androstenol formation from androstenone was six times higher than in M pigs. 3beta-hydroxysteroid dehydrogenase (3beta-HSD) was investigated as a likely candidate for the enzyme catalysing androstenone reduction in pig liver. RT-PCR analysis showed that there was no sequence difference in the cDNA encoding 3beta-hydroxysteroid dehydrogenase from LW and M pigs. However, competitive RT-PCR analysis showed that the expression of 3beta-hydroxysteroid dehydrogenase mRNA was about 12 times higher in the case of LW compared to M pigs. It is concluded that the rate of androstenone metabolism in pig liver microsomes is determined by the level of expression of hepatic 3beta-hydroxysteroid dehydrogenase. The differential expression of this enzyme could be a factor affecting the rate of hepatic androstenone metabolism which in turn may influence the level of hepatic CYP2E1 expression and hence the rate of hepatic skatole metabolism.     

Simultaneous quantification of five odorous steroids (16-androstenes) in the axillary hair of men

Five 16-androstenes have been simultaneously quantified in extracts of the axillary hair of men (age range 18-40 years) using combined capillary gas chromatography-mass spectrometry, with specific ion monitoring. Quantities found (pmol/mg.hair, with approximate 24-h totals in parentheses) were: 5 alpha-androst-16-en-3-one, 0-15 (0-433); 4, 16-androstadien-3-one, 0-143 (0-4103); 5,16-androstadien-3 beta-ol, 0-3.5 (0-728); 5 alpha-androst-16-en-3 alpha-ol, 0-17 (0-1752) and 5 alpha-androst-16-en-3 beta-ol, 0-4 (0-416). There were no significant relationships with age of the subjects for any of the steroids measured but significant relationships were found between the amounts of the two ketones and between 5 alpha-androst-16-en-3 alpha- and 3 beta-ols. These findings may indicate the existence of a pathway of metabolism in axillary bacteria in which 4,16-androstadien-3-one is reduced to 5 alpha-androst-16-en-3-one and thence to the 3 alpha- and 3 beta-alcohols. The data are discussed in the context of axillary odour because of the low olfactory thresholds of several of the 16-androstenes measured and because of the relatively large quantities found in some subjects.     

Factors affecting the pheromone composition of voided boar saliva

The pheromone binding protein 'pheromaxein' which binds the pheromonal 16-androstene steroids in the saliva of the male pig (boar), was degraded and lost its binding activity in saliva incubated in air for 72 h at 21 degrees C and 37 degrees C. However, pheromaxein and its binding activity were retained in saliva incubated for 168 h at 4 degrees C. When the 3H-labelled pheromones 5 alpha-androst-16-en-3 alpha-ol (3 alpha-androstenol), 5 alpha-androst-16-en-3-one (5 alpha-androstenone) and 5 alpha-androst-16-en-3 beta-ol (3 beta-androstenol) were incubated with boar saliva for 168 h at 21 degrees C, 3 alpha-androstenol was primarily converted to 5 alpha-androstenone and 5 alpha-androstenone to 3 beta-androstenol; 3 beta-androstenol was unchanged. Evidence was obtained for microorganisms being responsible for these steroid transformations.     

On the existence of receptors to the pheromonal steroid, 5 alpha-androst-16-en-3-one, in porcine nasal epithelium

The binding of the odorant, 5 alpha-androst-16-en-3-one, to porcine nasal tissues, has been investigated using methods normally employed for studying both cytosolic and membrane-bound receptors. 5 alpha-Androst-16-en-3-one was generally taken up more avidly by homogenates of olfactory (nervous) tissue than by respiratory tissue, but binding to the former was only partially prevented by prior heating or by excess ligand, suggesting some degree of specific binding. At low protein concentration, saturable binding was noted but these data were not reproducible. The binding of a non-odorant, DHA, was only 2% that of 5 alpha-androst-16-en-3-one. Using agarose gel electrophoresis, some evidence was obtained for binding protein(s) to the odorous 16-adrostene in porcine respiratory tissues, that were absent from previously heated tissue. Experiments with SDS-treated, or cell-membrane-enriched preparations, of nasal epithelium did not show improved binding of 5 alpha-androst-16-en-3-one. We conclude that the extreme hydrophobicity of 5 alpha-androst-16-en-3-one is probably responsible for the high degree of non-specific binding noted and for variability in results. This is discussed in relation to other known odorous ligand/receptors in olfactory tissue, particularly that of 5 alpha-androstan-3-one.     

Conversion of 5 alpha-pregnane-3,20-dione, 3 alpha-hydroxy-5 alpha-pregnan-20-one and 3 beta-hydroxy-5 alpha-pregnan-20-one to delta 16-C19 steroids by the reconstituted delta 16-C19-steroid synthetase system

The substrate specificity of the reconstituted delta 16-C19-steroid synthetase system, which catalyzes the formation of 5,16-androstadien-3 beta-ol or 4,16-androstadien-3-one from pregnenolone or progesterone, respectively, was studied. The reconstituted system consisted of a partially purified cytochrome P-450, NADPH-cytochrome P-450 reductase, cytochrome b5 and NADH-cytochrome b5 reductase all from pig testicular microsomes. It was found that 5 alpha-reduced C21 steroids such as 5 alpha-pregnane-3,20-dione, 3 alpha-hydroxy-5 alpha-pregnan-20-one and 3 beta-hydroxy-5 alpha-pregnan-20-one can be substrates for the enzyme system, resulting in the formation of 5 alpha-androst-16-en-3-one, 5 alpha-androst-16-en-3 alpha-ol and 5 alpha-androst-16-en-3 beta-ol, respectively. The results suggest that 5 alpha-reduced delta 16-C19 steroids might be synthesized from pregnenolone and progesterone via 5 alpha-reduced C21 steroids as intermediates. The pathways would bypass 5,16-androstadien-3 beta-ol and 4,16-androstadien-3-one which have been assumed as obligatory intermediates in the formation of 5 alpha-reduced delta 16-C19 steroids from pregnenolone and progesterone.     

Androgen metabolism by rat epididymis: 5. Metabolic conversion and nuclear binding after injection of 5α-androstane-3α,17β-diol, in vivo

The pattern of androgenic metabolites in blood, muscle, caput and cauda epididymidis has been investigated in functionally hepatectomized 24 hours castrated rats, 3 hours after the intra-muscular injection of 200 μCi of ³H -3α-diol. Identification of the radioactive metabolites showed only negligible differences between the epididymal regions. In both caput and cauda the main metabolite was DHT (17β-hydroxy-5α-androstane-3-one); 3α- and 3β-diol, androsterone (3α-hydroxy-5α-androstane-17-one), 5-A-dione (5α-androstane-3,17-dione), Δ¹⁶-3α-ol (5α-androst-l6-en-3α-ol), Δ¹⁶-3β-ol (5α-androst-l6-en-3α-ol) and Δ¹⁶-3-one (5α-androst-l6-en-3-one) were also present.$\text{Androsterone}$ and $\text{3α-diol}$ were the predominant metabolites in blood and muscle. No Δ¹⁶ compounds could be detected and in constrast to epididymis, more than 50% of the radioactivity was associated with polar compounds. From determination of total radioactivity, it was seen that retention by epididymis varied from two to four times that of muscle. Purification and identification of the radioactivity associated with the nuclear fraction demonstrated that DHT was the only nuclear bound androgen.It is suggested from these results that at least one effect of 3α-diol on the rat epididymis is exerted through its conversion to DHT.     

Studies on the biosynthesis of 16-dehydro steroids: The metabolism of [4-14C]pregnenolone by boar adrenal and testis tissue in vitro

1. The metabolism of [4-(14)C]pregnenolone in vitro by boar adrenocortical and testis tissue has been studied. 2. Boar testis tissue formed three labelled Delta(16)-steroids, 5alpha-androst-16-en-3alpha-ol, 5alpha-androst-16-en-3beta-ol and androsta-4,16-dien-3-one. In adrenal tissue very much smaller yields of the same metabolites were obtained. 3. Both tissues produced labelled progesterone, androst-4-ene-3,17-dione and testosterone in varying quantities. The amount of progesterone was about 120 times greater in the adrenal tissue. In testis tissue dehydroepiandrosterone was found only in small quantity. 4. A pathway is suggested for the biosynthesis of Delta(16)-steroids from pregnenolone in boar testis tissue. The possibility that progesterone may be an intermediate is discussed.     

Biosynthesis of androgens and pheromonal steroids in neonatal porcine testicular preparations

The biosynthesis of testosterone and 4-androstene-3,17-dione and some 16-androstenes has been studied in homogenates or subcellular fractions of testes from 3-week-old Landrace piglets. Pregnenolone was converted into 5,16-androstadien-3 beta-ol, 4,16-androstadien-3-one, 5 alpha-androst-16-en-3-one and 5 alpha-androst-16-en-3 alpha- and 3 beta-ols, but the quantities were some 50 times less than those formed in the mature boar testis. Androgens were also formed in the microsomal fractions but the quantities of 4-androstene-3,17-dione (from side-chain cleavage of 17-hydroxyprogesterone) and of testosterone (from reduction of 4-androstene-3,17-dione) were 50-70 times lower than in the adult animal. The kinetic parameters and cofactor preference of the 3 alpha- and 3 beta-hydroxysteroid dehydrogenases were determined in the cytosolic, microsomal and mitochondrial fractions of neonatal porcine testes.     

Positive relationship between menstrual synchrony and ability to smell 5alpha-androst-16-en-3alpha-ol

To explore the possibility that compounds which were identified as pheromones in experimental animals mediate human menstrual synchrony, we examined the relationship between menstrual synchrony and the ability to smell putative pheromones, 5alpha-androst-16-en-3alpha-ol (3alpha-androstenol) and 5alpha-androst-16-en-3-one (5alpha-androstenone). When we examined menstrual synchrony among 64 women living together in a college dormitory, we found that 24 (38%) of them became synchronized with room-mates in 3 months. Afterwards, dilution series of 3alpha-androstenol and 5alpha-androstenone and the control odorant (pyridine) were presented to the 64 women and sensitivity to the odors was compared between synchronized and non-synchronized women. No difference was found between the two groups of women in the detection threshold for pyridine, indicating that general olfactory ability did not differ between them. The detection threshold for 3alpha-androstenol of synchronized women was significantly lower than that of non-synchronized women, but no difference in the threshold for 5alpha-androstenone was found between synchronized and non-synchronized women. These results indicate that the women who showed menstrual synchrony had a higher sensitivity to 3alpha-androstenol but not necessarily to 5alpha-androstenone.     

Olfactory responsiveness to two odorous steroids in three species of nonhuman primates

Social communication by means of odor signals is widespread among mammals. In pigs, for example, the C19-steroids 5-alpha-androst-16-en-3-one and 5-alpha-androst-16-en-3-ol are secreted by the boar and induce the mating stance in the sow. In humans, the same substances have been shown to be compounds of body odor and are presumed to affect human behavior. Using an instrumental conditioning paradigm, we here show that squirrel monkeys, spider monkeys and pigtail macaques are able to detect androstenone at concentrations in the micromolar range and thus at concentrations at least as low as those reported in pigs and humans. All three species of nonhuman primates were considerably less sensitive to androstenol, which was detected at concentrations in the millimolar range. Additional tests, using a habituation-dishabituation paradigm, showed that none of the 10 animals tested per species was anosmic to the two odorous steroids. These results suggest that androstenone and androstenol may be involved in olfactory communication in the primate species tested and that the specific anosmia to these odorants found in approximately 30% of human subjects may be due to their reduced number of functional olfactory receptor genes compared with nonhuman primates.     

Effects of 5alpha-androst-16-en-3alpha-ol on the pulsatile secretion of luteinizing hormone in human females

We examined the effects of 5alpha-androst-16-en-3alpha-ol (3alpha-androstenol) on pulsatile luteinizing hormone (LH) secretion in human females. The frequency of the LH pulse in the follicular phase was decreased by exposing the women to 3alpha-androstenol.     

Headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) for the determination of 5alpha-androst-2-en-17-one and -17beta-ol in the female Asian elephant: application for reproductive monitoring and prediction of parturition

Asian elephants are not self-sustaining in captivity. The main reasons for this phenomenon are a low birth rate, an aging population, and poor calf-rearing. Therefore, it is essential that reproductive rates had to be improved and there is need for rapid quantitative measures to monitor reproductive functions focussing on estrous detection and the prediction of the period of parturition. The objective of this study was to develop a method which combines headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) for analyses of 5alpha-androst-2-en-17beta-ol and -17-one to prognose estrous and to predict the period of parturition. SPME was carried out with a CTC Combi Pal system.The course of the luteal phase-specific substance 5alpha-androst-2-en-17beta-ol and -17-one followed a cyclic pattern in which the follicular and luteal phases could be clearly distinguished (mean estrous cycle length, 15+/-1.4 weeks). Based on daily urine samples, estrous prognosis might be possibly based on the initial 5alpha-androst-2-en-17beta-o1 increase at the end of the follicular phase. Parturition prognosis was performed in three elephant cows based on the 5alpha-androst-2-en-17beta-o1 drop to baseline levels 5-4 days prior parturition. Experiments revealed that 5alpha-androst-3alpha-ol-17-one and probably 5alpha-androst-3alpha-ol-17beta-ol are generated from sulfate conjugates by a thermal process.