| SHBG | |||||||||||||||||||||||||||||||||||||||||||||||||||
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| Identifiers | |||||||||||||||||||||||||||||||||||||||||||||||||||
| Aliases | SHBG, ABP, SBP, TEBG, sex hormone binding globulin, Sex hormone-binding globulin | ||||||||||||||||||||||||||||||||||||||||||||||||||
| External IDs | OMIM:182205;MGI:98295;HomoloGene:813;GeneCards:SHBG;OMA:SHBG - orthologs | ||||||||||||||||||||||||||||||||||||||||||||||||||
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| Wikidata | |||||||||||||||||||||||||||||||||||||||||||||||||||
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| Androgen-binding protein, Sex hormone-binding globulin | |||||||
|---|---|---|---|---|---|---|---|
| Identifiers | |||||||
| Symbol | SHBG | ||||||
| Alt. symbols | ABP | ||||||
| NCBI gene | 6462 | ||||||
| HGNC | 10839 | ||||||
| OMIM | 182205 | ||||||
| RefSeq | NM_001040 | ||||||
| UniProt | P04278 | ||||||
| Other data | |||||||
| Locus | Chr. 17p13-p12 | ||||||
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Sex hormone-binding globulin (SHBG) orsex steroid-binding globulin (SSBG) is aglycoprotein that binds toandrogens andestrogens. When produced by theSertoli cells in theseminiferous tubules of thetestis, it is calledandrogen-binding protein (ABP).[5][6]
Othersteroid hormones such asprogesterone,cortisol, and othercorticosteroids are bound bytranscortin. SHBG is found in all vertebrates apart from birds.[7]
Testosterone and estradiol circulate in the bloodstream, loosely bound mostly toserum albumin (~54%), and to a lesser extent bound tightly to SHBG (~44%). Only a very small fraction of about 1 to 2% is unbound, or "free," and thus biologically active and able to enter acell and activate itsreceptor. SHBG inhibits the function of these hormones. Thus, the local bioavailability of sex hormones is influenced by the level of SHBG. Because SHBG binds totestosterone (T) anddihydrotestosterone (DHT), these hormones are made less lipophilic and become concentrated within the luminal fluid of the seminiferous tubules. The higher levels of these hormones enablespermatogenesis in theseminiferous tubules and sperm maturation in theepididymis. SHBG's production is regulated under the influence ofFSH[6] on Sertoli cells, enhanced byinsulin,retinol, andtestosterone.
The relative binding affinity of various sex steroids for SHBG isdihydrotestosterone (DHT) >testosterone >androstenediol >estradiol >estrone.[8] DHT binds to SHBG with about 5 times the affinity of testosterone and about 20 times the affinity of estradiol.[9]Dehydroepiandrosterone (DHEA) is weakly bound to SHBG, butdehydroepiandrosterone sulfate is not bound to SHBG.[8]Androstenedione is not bound to SHBG either, and is instead bound solely to albumin.[10]Estrone sulfate andestriol are also poorly bound by SHBG.[11] Less than 1% ofprogesterone is bound to SHBG.[12]
SHBG levels are usually about twice as high in women as in men.[9] In women, SHBG serves to limit exposure to bothandrogens andestrogens.[9] Low SHBG levels in women have been associated withhyperandrogenism andendometrial cancer due to heightened exposure to androgens and estrogens, respectively.[9] Duringpregnancy, due to activation of SHBG production in theliver by high estrogen levels, SHBG levels increase by five-fold to ten-fold.[9] The high SHBG levels during pregnancy may serve to protect the mother from exposure tofetal androgens that escapemetabolism by theplacenta.[9] Acase report of severe hyperandrogenism in a pregnant woman due to a rare instance of genetic SHBG deficiency illustrates this.[9][13]
SHBG is produced mostly by theliver and is released into the bloodstream. Other sites that produce SHBG include the brain, uterus, testes, and placenta.[14] Testes-produced SHBG is called androgen-binding protein.
Thegene for SHBG is calledShbg, located onchromosome 17[14] on the short arm between the bands 17p12→p13.[15] Overlapping on the complementary DNA strand is the gene forspermidine/spermine N1-acetyltransferase family member 2 (SAT2). Nearby are the genes forp53 andATP1B2, andfragile X mental retardation, autosomal homolog 2 (FXR2) on the complementary strand.[16] There are eight exons, of which exon 1 has three variations called 1L, 1T and 1N which are triggered by three promoters: PL, PT and PN respectively. SHBG comes with the 1L, 2, 3, 4, 5, 6, 7, and 8 exons connected together. A variation includes SHBG-T which is missing exon 7 but with exon 1T promoted by promoter PT on the opposite strand, which shared with that for SAT2.[17]
There are variations in the genetic material for this protein that have different effects.In humans common polymorphisms include the following:
Rs6259, also called Asp327Asn location 7633209 on chromosome 17, results in there being an extra N-glycosylation site, and so an extra sugar can be attached. This results in a longer circulation half-life for the protein, and raised levels. Health effects include a lowered risk ofendometrial cancer and an increased risk ofsystemic lupus erythematosus.[18]
Rs6258 also called Ser156Pro is at position 7631360 on chromosome 17.
Rs727428 position 7634474 is in several percent of humans.[19]
(TAAAA)(n) is five base pairs that repeats a variable number of times on the opposite DNA strand.[20]
The mechanism of activating the promoter for SHBG in the liver involveshepatocyte nuclear factor 4 alpha (HNF4A) binding to aDR1-likecis-element which then stimulates production. Competing with HNF4A at a third site on the promoter is PPARG-2 which reduces copying the gene to RNA. If the HNF4A level is low, thenCOUP-TF binds to the first site and turns off production of SHBG.[7]
Sex hormone-binding globulin is homodimeric, meaning it has two identical peptide chains making up its structure. The amino acid sequence is the same as for androgen-binding protein produced in testes, but with differentoligosaccharides attached.[14]
SHBG has two laminin G-like domains which form pockets that bind hydrophobic molecules. The steroids are bound by the LG domain at the amino end of the protein.[7] Inside the pocket of the domain is a serine residue that attracts the two different types of steroids at different points, thus changing their orientation. Androgens bind at the C3 functional groups on the A ring, and estrogens bind via a hydroxyl attached to C17 on the D ring. The two different orientations change a loop over the entrance to the pocket and the position of trp84 (in humans). Thus the whole protein signals what hormone it carries on its own surface.[7] The steroid binding LG domain is coded by exons 2 to 5.[7] A linker region joins the two LG domains together.[7]
When first produced, the SHBG precursor has a leading signal peptide attached with 29 amino acids. The remaining peptide has 373 amino acids.[21] There are two sulfur bridges.
The sugars are attached at two differentN-glycosylation points on asparagine (351 and 367) and oneO-glycosylation point (7) on threonine.[21]
A calcium ion is needed to link the two elements of the dimer together. Also a zinc ion is used to orient an otherwise disorganised part of the peptide chain.[7]
SHBG has both enhancing and inhibiting hormonal influences and thus can be viewed as ahepatokine. It decreases with high levels ofinsulin,growth hormone,insulin-like growth factor 1 (IGF-1),androgens,prolactin andtranscortin. Highestrogen andthyroxine levels cause it to increase.
In an effort to explain obesity-related reductions in SHBG, recent evidence suggests sugar or monosaccharide-inducedhepatic lipogenesis, hepatic lipids in general, and cytokines like TNF-alpha and interleukins reduce SHBG, whereas insulin does not. For example, anti-psoriatic drugs that inhibitTNF-alpha cause an increase in SHBG. The common downstream mechanism for all of these, including the effect of thyroid hormones,[22] was downregulation of hepatocyte nuclear factor 4 (HNF4).[23][24][25][26]
Reference ranges for blood tests for SHBG have been developed:[27][28]
| Population | Range |
|---|---|
| Adult female, premenopausal | 40–120 nmol/L |
| Adult female, postmenopausal | 28–112 nmol/L |
| Adult male | 20–60 nmol/L |
| Infant (1–23 months) | 60–252 nmol/L |
| Prepubertal (2–8 years) | 72–220 nmol/L |
| Pubertal female | 36–125 nmol/L |
| Pubertal male | 16–100 nmol/L |
_and_estradiol_levels_during_pregnancy_in_women.png)
SHBG levels aredecreased by androgens, administration ofanabolic steroids,[32]polycystic ovary syndrome (PCOS),hypothyroidism,obesity,Cushing's syndrome, andacromegaly. Low SHBG levels increase the probability oftype 2 diabetes.[33] SHBG levelsincrease with estrogenic states (oral contraceptives),pregnancy,hyperthyroidism,cirrhosis,anorexia nervosa, and certaindrugs. Long-termcalorie restriction increases SHBG in rodents and men, while lowering free and total testosterone and estradiol and having no effect onDHEA-S, which lacks affinity for SHBG.[34] PCOS is associated with insulin resistance and excess insulin lowers SHBG, which increases free testosterone levels.[35]
In utero, the human fetus has a low level of SHBG, allowing increased activity of sex hormones. After birth, the SHBG level rises and remains at a high level throughout childhood. At puberty the SHBG level halves in girls and goes down to a quarter in boys.[7] The change at puberty is triggered bygrowth hormone, and its pulsatility differs in boys and girls.[clarification needed] In the third trimester of pregnancy, the SHBG level of the parent escalates to five to ten times the usual level for a woman.[7][9] A hypothesis is that this protects against the effect of hormone produced by the fetus.[7]
Obese girls are more likely to have an earlymenarche due to lower levels of SHBG.[7] Anorexia or a lean physique in women leads to higher SHBG levels, which in turn can lead toamenorrhea.[7]
Reduced levels of SHBG and also certainpolymorphisms of the SHBG gene are implicated in the development ofinsulin resistance andtype 2 diabetes.[36] Such effects apparently involve direct action at the cellular level where it became apparent that cell membranes of certain tissues contain specific high-affinity SHBG receptors.[37]
SHBG is a useful correlate and indirect marker of estrogen-induced procoagulation and by extensionthrombosis, for instance withbirth control pills.[38][39][40]
Oral contraceptives containingethinylestradiol can increase SHBG levels 2- to 4-fold and decrease free testosterone concentrations by 40 to 80% in women.[41] They can be used to treatsymptoms ofhyperandrogenism likeacne andhirsutism.[41][9] Some oral contraceptives, namely those containing high doses of ethinylestradiol (which have been discontinued and are no longer marketed), can increase SHBG levels as much as 5- to 10-fold.[9]
Some medications, such as certainanabolic steroids likemesterolone anddanazol and certainprogestins likelevonorgestrel andnorethisterone, have high affinity for SHBG and can bind to it and displaceendogenoussteroids from it, thereby increasing free concentrations of these endogenous steroids.[42][43][44] It has been estimated that therapeutic levels of danazol,methyltestosterone,fluoxymesterone, levonorgestrel, and norethisterone would respectively occupy or displace from testosterone 83–97%, 48–69%, 42–64%, 16–47%, and 4–39% of SHBG binding sites, while others with low affinity for SHBG such asethinylestradiol,cyproterone acetate, andmedroxyprogesterone acetate would occupy or displace from testosterone 1% or fewer SHBG binding sites.[42][45]
Selective androgen receptor modulators (SARMs) also reduce SHBG.[46]
| Compound | Structure | SHBG RBA (%) | SHBG K (106 M−1) | CBG RBA (%) | CBG K (106 M−1) |
|---|---|---|---|---|---|
| Aminoglutethimide | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Androstanolone | Steroidal | 220 | 5500 | 1.3 | 0.83 |
| Betamethasone | Steroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Cholecalciferol | Steroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Cimetidine | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Clomifene | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Cortisol (hydrocortisone) | Steroidal | 0.13 | 1.6 | 100 | 76 |
| Cortisone acetate | Steroidal | 0.10 | 1.2 | <0.1 | <0.1 |
| Cyproterone acetate | Steroidal | 0.10 | 1.2 | <0.1 | <0.1 |
| Danazol | Steroidal | 18 | 240 | 10 | 6.5 |
| Dexamethasone | Steroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Diazoxide | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Diethylstilbestrol | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Digitoxin | Steroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Digoxin | Steroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| DL-DOPA | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Dopamine | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Enclomiphene | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Epinephrine | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Estradiol | Steroidal | 49 | 680 | <0.1 | <0.1 |
| Estradiol benzoate | Steroidal | 0.70 | 8.6 | <0.1 | <0.1 |
| Ethinylestradiol | Steroidal | 0.80 | 9.9 | <0.1 | <0.1 |
| Ethisterone | Steroidal | 55 | 780 | 0.33 | 0.21 |
| Fludrocortisone | Steroidal | <0.01 | <0.2 | 0.74 | 0.47 |
| Fluoxymesterone | Steroidal | 4.8 | 60 | <0.1 | <0.1 |
| Flutamide | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Homovanillic acid | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Hydrocortisone hemisuccinate | Steroidal | <0.01 | <0.2 | 8.7 | 5.6 |
| Indometacin | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Levonorgestrel | Steroidal | 31 | 420 | <0.1 | <0.1 |
| Medroxyprogesterone | Steroidal | 0.15 | 1.9 | 13 | 8.1 |
| Medroxyprogesterone acetate | Steroidal | 0.08 | 1.0 | 6.5 | 4.2 |
| Melatonin | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Mesterolone | Steroidal | 180 | 3600 | <0.1 | <0.1 |
| Mestranol | Steroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Methoxytryptophol | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Methyldopa | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Methylserotonin | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Methyltestosterone | Steroidal | 39 | 530 | <0.1 | <0.1 |
| Metiamide | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Metribolone | Steroidal | 1.7 | 21 | 0.36 | 0.23 |
| Metyrapone | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Mexrenone | Steroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Nafoxidine | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Nandrolone | Steroidal | 5.8 | 72 | 0.10 | 0.63 |
| Norepinephrine | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Norethisterone | Steroidal | 11 | 140 | 0.28 | 0.18 |
| Noretynodrel | Steroidal | 1.3 | 16 | 0.16 | 0.10 |
| Normetanephrine | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Phenytoin | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Potassium canrenoate | Steroidal | 0.18 | 2.2 | 0.83 | 0.53 |
| Prednisolone | Steroidal | 0.04 | 0.49 | 59 | 41 |
| Prednisone | Steroidal | 0.17 | 2.1 | 5.0 | 3.2 |
| Progesterone | Steroidal | 0.71 | 8.8 | 36 | 24 |
| Promegestone | Steroidal | 0.007 | 0.09 | 0.40 | 0.25 |
| Prorenone | Steroidal | 8.2 | 100 | <0.1 | <0.1 |
| Reserpine | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Rifampin | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Serotonin | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Spironolactone | Steroidal | 0.03 | 0.37 | <0.1 | <0.1 |
| Tamoxifen | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Testolactone | Steroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Testosterone | Steroidal | 100 | 1600 | 8.3 | 5.3 |
| Testosterone enanthate | Steroidal | 0.007 | 0.086 | <0.1 | <0.1 |
| 7α-Thioprogesterone | Steroidal | 0.06 | 0.74 | 36 | 24 |
| 7α-Thiospironolactone | Steroidal | 0.59 | 7.3 | <0.1 | <0.1 |
| Thyroxine | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Triiodothyronine | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Trimethyltrienolone | Steroidal | 0.90 | 11 | 0.11 | 0.07 |
| Vanillylmandelic acid | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| Zuclomifene | Nonsteroidal | <0.01 | <0.2 | <0.1 | <0.1 |
| The referenceligands (100%) for theRBATooltip relative binding affinity (%) values weretestosterone for SHBG andcortisol forCBGTooltip corticosteroid-binding globulin. | |||||
| Progestogen | SHBG (%) | CBG (%) |
|---|---|---|
| 17α-Allyl-19-nortestosterone | <1 | ? |
| Allylestrenol | <1 | ? |
| Chlormadinone acetate | <1 | <1 |
| Cyproterone acetate | <1 | <1 |
| Desogestrel | <1 | <1 |
| Dienogest | <1 | <1 |
| Drospirenone | <1 | <1 |
| Etonogestrel | 15 | <1 |
| Gestodene | 40 | <1 |
| Levonorgestrel | 50 | <1 |
| Medroxyprogesterone acetate | <1 | <1 |
| Megestrol acetate | <1 | <1 |
| Nomegestrol acetate | <1 | <1 |
| Norelgestromin | <1 | ? |
| Norethisterone | 16 | <1 |
| Noretynodrel | <1 | <1 |
| Norgestimate | <1 | <1 |
| Progesterone | <1 | 36 |
| Promegestone | <1 | <1 |
| Segesterone acetate | <1 | ? |
| Δ4-Tibolone | 1 | <1 |
| Values areRBAsTooltip relative binding affinities (%). The referenceligand (100%) for SHBG wasdihydrotestosterone and forCBGTooltip corticosteroid-binding globulin wascortisol. | ||
| Compound | SHBG (%) |
|---|---|
| 5α-Androstane-3β,17β-diol | 17 |
| 5β-Androstane-3α,17β-diol | 5 |
| Dihydrotestosterone | 100 |
| Ethylestrenol | <1 |
| Fluoxymesterone | <1 |
| Mesterolone | 440 |
| Metandienone | 2 |
| Metenolone | 3 |
| Methyltestosterone | 5 |
| Metribolone | <1 |
| Nandrolone | 1 |
| Oxymetholone | <1 |
| Stanozolol | 1 |
| Testosterone | 19 |
| Values areRBAsTooltip relative binding affinities (%). The referenceligand (100%) for SHBG wasdihydrotestosterone. | |
| Compound | SHBG (%) |
|---|---|
| 3β-Androstanediol | 100 |
| Androstenediol | 77 |
| Bolandiol | 24 |
| Dihydroethisterone | 100 |
| Dihydroethyltestosterone | 18–21 |
| Dihydromethylandrostenediol | 77 |
| Dihydronandrolone | 44 |
| Dihydrotestosterone | 100 |
| Dihydrotrestolone | 47 |
| 4,17α-Dimethyltestosterone | 97 |
| Drostanolone | 39 |
| Ethisterone | 92 |
| Fluoxymesterone | 3 |
| 11-Ketodihydrotestosterone | 0 |
| Medroxyprogesterone acetate | 16 |
| Megestrol acetate | 0 |
| Mestanolone | 84 |
| Methasterone | 58 |
| Methyl-1-testosterone | 69 |
| Methylandrostenediol | 40 |
| Methyltestosterone | 64 |
| Mibolerone | 6 |
| Nandrolone | 16 |
| Nandrolone decanoate | 0 |
| Nandrolone phenylpropionate | 0 |
| Norethandrolone | 3 |
| Norethisterone | 21 |
| Normethandrone | 7 |
| Oxandrolone | 0 |
| Oxymetholone | 3 |
| Progesterone | 13 |
| Stanozolol | 36 |
| 1-Testosterone | 98 |
| Testosterone | 82 |
| Testosterone benzoate | 8 |
| Testosterone cypionate | 6 |
| Testosterone enanthate | 9 |
| Δ4-Tibolone | 8 |
| Trestolone | 12 |
| Trestolone enanthate | 12 |
| Vinyltestosterone | 36 |
| Values areRBAsTooltip relative binding affinities (%). The referenceligand (100%) for SHBG wasdihydrotestosterone. | |
| Compound | SHBGTooltip Sex hormone-binding globulin (%) | CBGTooltip Corticosteroid binding globulin (%) | ||||||
|---|---|---|---|---|---|---|---|---|
| Aldosterone | <0.2 | 6.0 | ||||||
| Corticosterone | <0.2 | 107 | ||||||
| Cortisol | <0.2 | 100 | ||||||
| Dexamethasone | <0.2 | <0.1 | ||||||
| Dihydrotestosterone | 100 | 0.8 | ||||||
| Estradiol | 8.7 | <0.1 | ||||||
| Metribolone | 0.2 | <0.1 | ||||||
| Moxestrol | <0.2 | <0.1 | ||||||
| Progesterone | <0.2 | 25 | ||||||
| Promegestone | <0.2 | 0.9 | ||||||
| Testosterone | 26 | 3 | ||||||
| Values areRBAsTooltip relative binding affinities (%). The referenceligand (100%) for SHBG wasdihydrotestosterone and forCBGTooltip corticosteroid-binding globulin wascortisol. | ||||||||
| Compound | RBATooltip Relative binding affinity to SHBGTooltip sex hormone-binding globulin (%) | Bound to SHBG (%) | Bound to albumin (%) |
|---|---|---|---|
| 17β-Estradiol | 50 | 37 | 61 |
| Estrone | 12 | 16 | 80 |
| Estriol | 0.3 | 1 | 91 |
| Estrone sulfate | 0 | 0 | 99 |
| 17β-Dihydroequilin | 30 | ? | ? |
| Equilin | 8 | 26 | 13 |
| 17β-Dihydroequilin sulfate | 0 | ? | ? |
| Equilin sulfate | 0 | ? | ? |
| Δ8-Estrone | ? | ? | ? |
| The referenceligand (100%) for the SHBGRBATooltip relative binding affinity (%) values wastestosterone. | |||
When checking serum estradiol or testosterone, a total level that includes free and bound fractions can be assayed, or the free portion may be measured alone. Sex hormone-binding globulin can be measured separately from the total fraction of testosterone.
Afree androgen index expresses the ratio of testosterone to SHBG and can be used to summarize the activity of free testosterone.
| Steroid | SHBG affinity | Plasma protein binding in men | Plasma protein binding in women (follicular phase) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| RBA (%) | K (106 M−1) | Total (nM) | Unbound (%) | SHBG (%) | CBG (%) | Albumin (%) | Total (nM) | Unbound (%) | SHBG (%) | CBG (%) | Albumin (%) | |
| Aldosterone | 0.017 | 0.21 | 0.35 | 37.1 | 0.10 | 21.2 | 41.6 | 0.24 | 36.8 | 0.23 | 21.9 | 41.2 |
| 3α-Androstanediol | 82 | 1300 | 0.41 | 0.85 | 13.7 | <0.1 | 85.5 | 0.068 | 0.71 | 27.9 | <0.1 | 71.4 |
| Androstenediol | 97 | 1500 | 4.3 | 3.24 | 60.4 | <0.1 | 36.3 | 2.4 | 1.73 | 78.8 | <0.1 | 19.4 |
| Androstenedione | 2.3 | 29 | 4.1 | 7.85 | 2.82 | 1.37 | 88.0 | 5.4 | 7.54 | 6.63 | 1.37 | 84.5 |
| Androsterone | 1.1 | 14 | 2.0 | 4.22 | 0.73 | 0.52 | 94.5 | 1.5 | 4.18 | 1.77 | 0.54 | 93.5 |
| Corticosterone | 0.18 | 2.2 | 12 | 3.39 | 0.09 | 77.5 | 19.0 | 7.0 | 3.28 | 0.22 | 78.1 | 18.4 |
| Cortisol | 0.13 | 1.6 | 400 | 3.91 | 0.08 | 89.5 | 6.57 | 400 | 3.77 | 0.18 | 89.7 | 6.33 |
| Cortisone | 0.22 | 2.7 | 72 | 16.2 | 0.54 | 38.0 | 45.3 | 54 | 15.8 | 1.30 | 38.6 | 44.3 |
| Dehydroepiandrosterone | 5.3 | 66 | 24 | 4.13 | 3.38 | <0.1 | 92.4 | 17 | 3.93 | 7.88 | <0.1 | 88.1 |
| 11-Deoxycorticosterone | 1.9 | 24 | 0.20 | 2.69 | 0.80 | 36.4 | 60.1 | 0.12 | 2.62 | 1.91 | 36.9 | 58.6 |
| 11-Deoxycortisol | 1.3 | 16 | 1.4 | 3.37 | 0.67 | 77.1 | 18.9 | 0.60 | 3.24 | 1.57 | 77.1 | 18.1 |
| Dihydrotestosterone | 220 | 5500 | 1.7 | 0.88 | 59.7 | 0.22 | 39.2 | 0.65 | 0.47 | 78.4 | 0.12 | 21.0 |
| Estradiol | 49 | 680 | 0.084 | 2.32 | 19.6 | <0.1 | 78.0 | 0.29 | 1.81 | 37.3 | <0.1 | 60.8 |
| Estriol | 0.35 | 4.3 | 0.037 | 8.15 | 0.44 | <0.2 | 91.3 | 0.10 | 8.10 | 1.06 | <0.2 | 90.7 |
| Estrone | 12 | 150 | 0.081 | 3.96 | 7.37 | <0.1 | 88.6 | 0.23 | 3.58 | 16.3 | <0.1 | 80.1 |
| Etiocholanolone | 0.11 | 1.4 | 1.3 | 8.15 | 0.14 | 0.44 | 91.3 | 1.2 | 8.13 | 0.35 | 0.46 | 91.1 |
| Pregnenolone | 1.1 | 14 | 2.4 | 2.87 | 0.50 | 0.16 | 96.5 | 2.2 | 2.85 | 1.21 | 0.16 | 95.8 |
| 17α-Hydroxypregnenolone | 0.19 | 2.3 | 5.4 | 4.27 | 0.12 | <0.1 | 95.5 | 3.5 | 4.26 | 0.30 | <0.1 | 95.4 |
| Progesterone | 0.71 | 8.8 | 0.57 | 2.39 | 0.26 | 17.2 | 80.1 | 0.65 | 2.36 | 0.63 | 17.7 | 79.3 |
| 17α-Hydroxyprogesterone | 0.8 | 9.9 | 5.4 | 2.50 | 0.31 | 41.3 | 55.9 | 1.8 | 2.44 | 0.73 | 42.1 | 54.7 |
| Testosterone | 100 | 1600 | 23 | 2.23 | 44.3 | 3.56 | 49.9 | 1.3 | 1.36 | 66.0 | 2.26 | 30.4 |
| In men, the concentrations of SHBG, CBG, and albumin were 28 nM, 0.7 μM, and 0.56 mM, respectively. In women, the concentrations of SHBG, CBG, and albumin were 37 nM, 0.7 μM, and 0.56 mM, respectively. | ||||||||||||
SHBG has been known under a variety of different names including:[52][53][54]
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