Bill Struthers (U60376 at uicvm.uic.edu) wrote:
: I'm looking for any information on the effectiveness of implanting estrogen
: capsules subcutaneously in OVX female rats. I am currently using Estradiol
: benzoate dissolved in sesame oil at 10ug/.2ml injected sc at 53 and 24 hours
: prior to sexual testing (along with 1mg progesterone 5hrs prior to testing).
: The effectiveness (and inconvenience) of this regimen is very inconsistent.
: I usually have about a 75% receptivity rate. My question is; Is implantation
: of Estrogen capsules, providing a constant supply of free released Estrogen,
: followed by progesterone injections, effective in producing sexual receptivity
: and how reliable is this regimen?
: Thanks for any help.
: Bill Struthers
:u60376 at uicvm.uic.edu
Bill:
Either method should work fine, and which one you use depends on the applic-
ation. The advantage of the capsules is that the animals can be brought
into sexual receptivity repeatedly and relatively effortlessly (for you)
about once a week. The disadvantage is that the hormonal pattern bears no
resemblance to the estrous cycle. 75 % is a bit low for the regimen
that you are using, so I would also wonder what might be causing this
relatively low level for such a relatively high priming dose.
Jeffrey D. Blaustein
Professor of Neuroscience and Behavior and Psychology
University of Massachusetts
Amherst, MA 01003-7710