From: Emlyn (emlyn@one.net.au)
Date: Mon Nov 06 2000 - 02:49:38 MST
Nice stuff.
Hey, if this is happening to women, what happens to men? We do die younger,
after all.
Emlyn
Damien wrote:
> I believe it's been done. But maybe you're thinking of this passage from
> THE LAST MORTAL GENERATION:
>
> ===========
>
> Menopause marks a change in a body's response to these pituitary messages,
> largely because a woman's ovaries are finally depleted of eggs. Unlike
men,
> who keep producing spermatozoa all their lives, girls are born with a
> limited supply. Once all the eggs are gone, the ovaries can no longer
> respond to LH and FSH, even in elevated quantities - so other hormones
> necessary for health, chemical messengers formerly made in those tissues,
> simply dry up.
> That fact that ova are a finite resource is a reflection of the
> evolutionary history of human ageing. A human female foetus contains a
> startling seven millions eggs, which are screened and shed in vast
> profusion during the course of her mother's pregnancy. At birth, the
number
> of ova in the new-born girl child is down to a million, and the number
> keeps dropping through life - a quarter of a million at puberty, only
> 25,000 by around age 40. When a mere thousand or so remain, the subtle
> feedback between pituitary and ovaries starts to shut down.
> It has been suggested that surgically removing and freezing some of this
> wasted ovary tissue, transplanting it back in late middle age, might serve
> to extend the hormonal protection granted to the reproductively able.
> Indeed, experiments have shown that implanting ovary tissues from aborted
> female foetuses (which contain, as mentioned, a huge supply of egg cells)
> can extend an adult's sexual window. This is regarded by many as a
> repugnant option, and has been banned in some countries, but the point
> remains - it is the loss of eggs that activates the doleful cascade of
> menopause, not the other way around.
> Once that happens, then, a menopausal woman's reproductive hormone system
> starts to shut down, and the long-term consequences for the whole female
> body are well-nigh catastrophic. As the least of her problems, fat is laid
> down more readily in some places and less so in others, so an older
woman's
> body is likely to thicken and sag even as her features hollow and wrinkle.
> Her bones grow brittle. And, for a time, `hot flushes' suffuse the whole
> body as blood suddenly rushes into a woman's surface tissues, trying to
> cool a body confused by the abrupt drop in levels of oestrogen. Luckily,
> well-tailored Hormone Replacement Therapy can compensate for many of these
> uncomfortable and injurious side-effects.
> So is menopause a selected, organised change in the human body's dynamic,
> like the growth spurt and onset of sexual maturity in adolescence? Or is
it
> something more alarming - a simple failure of one life-support system
after
> another, driven by the loss of ova, the exhaustion of the ovaries, and the
> consequent failure of all the reproductive machinery? Is the female human
> body coded genetically to `degrade gracefully', as an engineer might put
> it, or is post-menopause life just whatever happens after the final page
of
> the manual is turned and nothing more is written?
> Hormone replacement therapy already shows that we can stall some of these
> uncomfortable and damaging changes, although sometimes at a price. [...]
>
> ==================
>
> Damien Broderick
>
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