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Atrophy of gonadotrophin producing cells Exogenously LH synthesis
administered androgens and release or anabolic steroids are
decreased Prostate Testes Normal function. Testosterone synthesis
in The deficit of endogenously Leydig cells is decreased. The
synthesized testosterone is exogenously administered compensated
for by the steroid is not able to exogenously administered
compensate for the deficit of steroid endogenously synthesized
testosterone Figure 2 Intratesticular and serum testosterone
concentrations after treatment with andro gens or anabolic steroids
in order to substitute for the peripheral androgen deficiency and
to achieve azoospermia. Because this steroid is alkylated in
position 17, toxic effects on liver function can not be excluded.
Danazol offers no advantages as compared with other anabolic
steroids; rather, disadvantages. Numerous experiments of this type
have been performed during the last 40 or 50 years. The outcome in
each case was more or less identical: with a certain dose of an
androgen or anabolic steroid it is possible to inhibit
spermatogenesis without interfering with other androgen-dependent
func tions, including libido (potentia coeundi) and accessory
sexual glands. On the basis of this
pharmacological-endocrinological background, androgens and anabolic
steroids can be used for male fertility control, and several
clinical trials have been performed during the last 10-15 years.
Some of 1 these studies 2-23 are mentioned in Table 2."
It is well established that progesterone plays a role in the brain
and hypophysis as a facilitator and inhibitor of sexual behavior
and gonadotropin release in the female rat (Everett 1961; Caligaris
et al. 1971; Brown-Grant and Naftolin 1972; Dorner 1972; Meyerson
1972; Barraclough 1973; Goldman and Zarrow 1973; Mann and
Barraclough 1973; Freeman et al. 1976; Feder and Marrone 1977;
Goodman 1978; Attardi 1981), guinea pig (Morin and Feder 1974), and
primates (Odell and Swerdloff 1968; Spies and Niswender 1972;
Yamaji et al. 1972; Karsch et al. 1973; Dierschke et al. 1973;
Knobi11974; Clifton et al. 1975). In an attempt to learn whether a
specific progesterone uptake mechanism exists in the brain and the
hypophysis, the distribution and retention pattern of radioactivity
after in vivo injection of labeled progesterone was studied. Early
work of Kato (1963) did not show a selective uptake of
radioactivity in the hypo- thalamus of immature and estrogen-primed
immature rats after injection oflow- specific-activity
[14C]progesterone, but some tendency of the reticular formation to
take up radiation was observed. Laumas and Farooq (1966) reported
that after intravenous administration of labeled progesterone to
ovariectomized estrogen- treated rats, radioactivity in the brain
and pituitary appeared to show a very slight, insignificant
increase 1-2 min after injection, but the uptake pattern was not
definite, as had been seen with estradiol. Seiki et al.
In 1920, Hirose demonstrated the luteinising effect of placental
tissue and one year later, Evans and Long described luteinised
ovaries in rats treated with hypophysial extracts. In 1926, Zondek
and Aschheim as well as Smith, independently of each other, showed
that a gonad-stimulating hormone was secreted by the
adenohypophysis. In 1927, Aschheim and Zondek found their "Prolan"
in human pregnancy urine and the first reliable pregnancy test was
available. In the following years it could be demonstrated that the
gonadotropic hormones from pituitary and from pregnancy urin were
not of identical structure. During the years 1931 - 1933 Fevold and
coworkers prepared follicle stimulating hormone from sheep
pituitaries which were free of other hormone activities. Already in
1934, Collip found "antihormones" in animals treated with
proteinhormones from animals of another species. It could be shown
that they were antibodies against these hormones and this was the
future basis for the immunological era starting in 1960. The
quantitative determination of gonadotropins has been performed over
several decades by difficult bioassays and since 1960 immunological
and later radioimmunological assays became available. Since that
time a new field was opened for the studies of gonadotropins.
During this time, highly purified preparations of gonadotropins
were available for research and clinical treatment. I recall the
first successful attempt of inducing follicle growth and ovulation
by Gemzell and coworkers 1958 as well as by Lunenfeld and
Bettendorf at about the same time.
Diese beiden Nachfolgebande der "Gynakologischen Endokrinologie"
(1987) signalisieren bereits im Titel die Erweiterung des
Fachgebiets, die aus den zahlreichen Neuentwicklungen der letzten
Jahre resultiert. Hierzu zahlen z.B. der Nachweis und die Bedeutung
neuer Hormone, Wachstumsfaktoren, neue Funktionsteste, die Therapie
mit weiblichen Sexualhormonen, die Untersuchung von
Umwelteinwirkungen sowie diagnostische und operative Techniken der
Fertilitatschirurgie. Mit diesen beiden Buchern sind Sie umfassend
uber den aktuellen Kenntnisstand dieser Spezialgebiete informiert.
Mit ihren zahlreichen Graphiken und Tabellen sowie ihrem
ausgezeichneten Bildmaterial werden die Bande Gynakologische
Endokrinologie und Fortpflanzungsmedizin fur AErzte in der Klinik
wie auch in der Praxis ein standiger Begleiter sein.
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