Risa wrote after Lupron was tried for her little one without testing
first:
>PS I agree, it's crazy to have put her on lupron without testing for
>adrenal.
 
Not really.  Lupron is a very safe drug in general for ferrets and some
vets do that trick as a check just in case with ones whose symptoms are
not conclusive because in doing so you find out if the signs change and
you provide a bit of treatment which in testing does reduce some of the
adrenal growths.  (On-going veterinary research shows some growths
continuing to grow after Lupron is given but some remain stable and
others actually reduce in size.  It is postulated that the more
responsive ones are the milder types of growths.  Compare to melatonin
which so far in ferrets has had some growths stall but has not reduced
growths in ferrets though it is has in some rodent and lagomorph testing.
The two can be used together, BTW, for greater effect.)
 
Lupron is also given in the Spring to try to stop the hormonal cycle
that has strong evidence of being an adrenal growth precursor (on-going
vet research).  Some vets think that with all of the use of artificial
lighting a Spring injection only won't be enough, so you will read of
others who are instead giving Lupron year-round as a possible
preventative, and veterianary research is also on-going with other meds.
 
You will also read of veterinary testing of melatonin as a possible
preventative as well as a treatment.  Be sure to see
http://www.miamiferret.org/fhc,
as well as the current issue of "Ferrets" magazine.
 
Here is basically what is thought to be going on.  The adrenal growth
hypothesis which combines too much light exposure especially with sexual
sterilization is still hypothetical, but it has very few gaps in the
knowledge at this point in time (unlike some other possible useful
measures such as the reduced carb diets to hopefully reduce insulinoma
rates (which may well wind up working -- or not -- but currently is based
on about 5 stacked hypotheses beginning with work on diabetes in cats so
has a lot of knowledge blanks which need filling as well as having a need
of getting basic rates which -- believe it or not -- are still not known
according to vets I have asked who are doing endocrinological research
and including some who have strong hopes for the hypothesis).
 
With the adrenal growth hypothesis the increased exposure to light (very
little COMPLETE darkness -- not just dimness) reacts as the Spring
increase in day length reacts in ferret bodies.  First the pineal stops
making as much melatonin.  Melatonin is a natural body product that is
made is response to darkness, esp.  deep darkness, which has multiple
uses; it is even a strong antioxidant.
 
When there is less melatonin in the body the pituitary responds by
increasing the production of Follicle Stimulating Hormone (FSH) and
Luteinizing Hormone (LH).  BTW, there are indications in human research
that increased production of FSH is a direct cause of osteoporosis.
Okay, there is the pituitary and it is sending out signals to begin the
Spring mating BUT there are not gonads to send the proper signals back
in response.  Without those return signals the pituitary just keeps
transmitting its hormonal signals.
 
Now, reproductive tissue is NOT the only sexual hormone producing tissue
in the body, which is good because the androgens and estrogens are used
for a lot of things in the body.  So far in what is known, there are
dozens of things -- like muscle maintenance -- that the androgens help
with, and hundreds of things that the estrogens help with -- including
some brain functions.  Also, the body can modify these hormones into each
other.  Fat is one of the very hormonally active tissues which can
produce such hormones, and the adrenals can, too.
 
So, without reproductive tissue to respond it is thought that the adrenal
tissue reacts to the increase in LH but since it can't produce what is
needed to turn off the signal it just reacts and reacts till it begins to
respond to the irritation of it all.
 
Melatonin can trick the pituitary into thinking that it is finally
getting more darkness -- which is a help but as we know with whole
ferrets about 60% of females stay in heat if they are not bred even with
season changes, so darkness hormone is not necessarily enough to stop the
signals.  Lupron works to stop the signals, as do similar compounds such
as the less expensive Suprelorin which is not yet available in the U.S.,
but its maker has applied for permission to sell it here as a veterinary
drug.
 
Some other possible causes of fur loss: seasonal, malnutrition,
mechanical, extended use of high level Pred doses, some few apparently
genetic with age, etc.
[Posted in FML issue 4843]