Biomaterial Database

Plasma progesterone concentrations in pregnant and non-pregnant black bears (Ursus americanus). 1983

K R Foresman, and J C Daniel

Plasma levels of progesterone were determined from serial samples taken from 2 black bears over 3 consecutive fall periods. Each animal was pregnant during the 1st and 3rd years. Variations in progesterone levels were seen between animals and within each animal between pregnancies. Average baseline levels during the mid-to-late preimplantation period were 5.0-12.5 ng/ml and increased 2-3 fold at the approximate time of implantation. Values during non-pregnancy were detectable but much lower (0.6-2.5 ng/ml). The observed pattern of progesterone secretion in this species appears consistent with that reported for other species exhibiting obligate delayed implantation.

UI	MeSH Term	Description	Entries
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011270	Pregnancy, Animal	The process of bearing developing young (EMBRYOS or FETUSES) in utero in non-human mammals, beginning from FERTILIZATION to BIRTH.	Animal Pregnancies,Animal Pregnancy,Pregnancies, Animal
D011374	Progesterone	The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.	Pregnenedione,Progesterone, (13 alpha,17 alpha)-(+-)-Isomer,Progesterone, (17 alpha)-Isomer,Progesterone, (9 beta,10 alpha)-Isomer
D002335	Carnivora	An order of MAMMALS, usually flesh eaters with appropriate dentition. Suborders include the terrestrial carnivores Fissipedia, and the aquatic carnivores CANIFORMIA.
D005260	Female		Females
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001503	Ursidae	The family of carnivorous or omnivorous bears, having massive bodies, coarse heavy fur, relatively short limbs, and almost rudimentary tails.	Ailuropoda,Bears,Black Bears,Giant Pandas,Grizzly Bears,Pandas, Giant,Pandas, Greater,Polar Bears,Spectacled Bear,Tremarctos,Ursus,Bear,Bear, Black,Bear, Grizzly,Bear, Polar,Bear, Spectacled,Bears, Black,Bears, Grizzly,Bears, Polar,Bears, Spectacled,Black Bear,Giant Panda,Greater Panda,Greater Pandas,Grizzly Bear,Panda, Giant,Panda, Greater,Polar Bear,Spectacled Bears