Ca. Frye et al., PROGESTERONE AND 3-ALPHA-ANDROSTANEDIOL CONJUGATED TO BOVINE SERUM-ALBUMIN AFFECTS ESTROUS BEHAVIOR WHEN APPLIED TO THE MBH AND POA, Behavioral neuroscience, 110(3), 1996, pp. 603-612
Ovariectomized rats with cannula over the medial basal hypothalamus (M
BH) received implants of 3 alpha-diol conjugated to bovine serum album
in (BSA; 3 alpha-diol:BSA), free 3 alpha-diol diluted with BSA (3 alph
a-diol&BSA), progesterone (P) conjugated to BSA (P:BSA), free P dilute
d with BSA (P&BSA), or BSA alone. 3 alpha-diol:BSA or 3 alpha-diol&BSA
facilitated receptivity within 90 min. Other estradiol-treated rats r
eceived steroid implants in the preoptic area (POA); those receiving P
:BSA or P&BSA showed significant elevations in lordosis in 5 min. When
systemic P was given, 3 alpha-diol:BSA and 3 alpha-diol&BSA applied t
o the MBH or POA inhibited receptivity. When 3 alpha-diol was given sy
stemically, 3 alpha-diol:BSA implants to the MBH and POA produced faci
litatory effects. These data suggest 3 alpha-diol can act at the membr
ane and that these effects are influenced by circulating steroids; yet
membrane-mediated actions do not account for all of P-facilitated sex
ual behavior in the MBH and POA.