Serum 17alpha-hydroxyprogesterone concentrations during the reproductive cycle in healthy dogs and dogs with hyperadrenocorticism.
OBJECTIVE
To determine concentrations of 17alpha-hydroxyprogesterone (17OHP) in serum of healthy bitches during various stages of the reproductive cycle and in bitches with hyperadrenocorticism and to compare the dynamics of 17OHP with those of progesterone.


METHODS
Prospective evaluation study.


METHODS
15 healthy sexually intact bitches and 28 spayed bitches with hyperadrenocorticism.


METHODS
11 healthy bitches were evaluated during estrus, nonpregnant diestrus, and anestrus (group 1); 4 other healthy bitches were evaluated during pregnancy and after ovariohysterectomy (group 2). Cycle stages were determined via physical examination, vaginal cytologic evaluation, and serum progesterone concentration. Bitches with hyperadrenocorticism were evaluated once at the time of diagnosis (group 3). Serum hormone concentrations were determined with immunoassays.


RESULTS
In group 1, the serum 17OHP concentration was significantly higher in diestrus (median, 1.8 ng/mL) than in estrus (median, 1.1 ng/mL) and anestrus (median, 0.2 ng/mL) and higher in estrus than in anestrus. Changes in serum progesterone concentrations accounted for 22% (estrus) or 23% (diestrus) of the variation in serum 17OHP concentrations. In group 2, 17OHP and progesterone concentrations were significantly higher during pregnancy than after ovariohysterectomy. The serum 17OHP concentration in group 3 was significantly lower (median, 0.2 ng/mL) than in group 1 in estrus and diestrus and in group 2 during pregnancy (median, 0.7 ng/mL) but was not different from 17OHP concentrations in anestrus or after ovariohysterectomy (median, 0.2 ng/mL).


CONCLUSIONS
Serum 17OHP concentrations in healthy bitches increased during estrus, diestrus, and pregnancy and at those times were higher than in spayed bitches with hyperadrenocorticism.
Department of Population Health and Reproduction, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA. cbroemel@ucdavis.edu
Catharina
C
Brömel
Edward C
EC
Feldman
Autumn P
AP
Davidson
Richard W
RW
Nelson
Philip H
PH
Kass
Alejandro
A
Esteller Vico
Philippe
P
Labelle
Coralie J
CJ
Munro
Alan J
AJ
Conley
D019326:17-alpha-Hydroxyprogesterone / Q000097:blood*; D000308:Adrenocortical Hyperfunction / Q000097:blood / Q000662:veterinary*; D000818:Animals; D016022:Case-Control Studies; D004283:Dog Diseases / Q000097:blood*; D004285:Dogs; D030762:Estrous Cycle / Q000097:blood* / Q000502:physiology*; D005260:Female; D011247:Pregnancy
D019326:17-alpha-Hydroxyprogesterone