Biomaterial Database

Inverse relationship of prolactin and rat placental lactogen during pregnancy. 1982

J Voogt, and M Robertson, and H Friesen

Serum prolactin, progesterone and rat placental lactogen (rPL) were measured in pregnant rats following removal of various numbers of conceptuses and their placentas on Day 8 of pregnancy. Blood samples were taken during the time of the expected nocturnal surge of prolactin on Days 8 and 9, and at the same time on Days 11 and 14 of pregnancy, when the surges are normally no longer present. As the number of conceptuses present decreased, the number of days the prolactin surge was present increased. Measurement of the early form of rPL (rPL-I) by lymphoma cell bioassay revealed a proportionate decrease in serum rPL-I levels on Days 9 and 11 as the number of conceptuses was decreased. This also was true for the late form of rPL (rPL-II) when measured by RIA on Day 14 of pregnancy. Thus, as rPL levels are reduced, prolactin surges remain present for increased numbers of days. This suggests that rPL may normally be an inhibitory factor to prolactin secretion during pregnancy, and is responsible for the termination of the prolactin surges at midpregnancy.

UI	MeSH Term	Description	Entries
D008098	Litter Size	The number of offspring produced at one birth by a viviparous animal.	Litter Sizes,Size, Litter,Sizes, Litter
D009929	Organ Size	The measurement of an organ in volume, mass, or heaviness.	Organ Volume,Organ Weight,Size, Organ,Weight, Organ
D010928	Placental Lactogen	A polypeptide hormone of approximately 25 kDa that is produced by the SYNCYTIOTROPHOBLASTS of the PLACENTA, also known as chorionic somatomammotropin. It has both GROWTH HORMONE and PROLACTIN activities on growth, lactation, and luteal steroid production. In women, placental lactogen secretion begins soon after implantation and increases to 1 g or more a day in late pregnancy. Placental lactogen is also an insulin antagonist.	Choriomammotropin,Chorionic Somatomammotropin, Human,Human Placental Lactogen,Lactogen Hormone, Placental,Mammotropic Hormone, Placental,Somatomammotropin, Chorionic,Choriomammotrophin,HCS (Human Chorionic Somatomammotropin),HPL (Human Placental Lactogen),PAPP-D,Placental Luteotropin,Pregnancy-Associated Plasma Protein D,Chorionic Somatomammotropin,Human Chorionic Somatomammotropin,Lactogen, Placental,Luteotropin, Placental,Placental Lactogen, Human,Placental Mammotropic Hormone,Pregnancy Associated Plasma Protein D
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
D011388	Prolactin	A lactogenic hormone secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). It is a polypeptide of approximately 23 kD. Besides its major action on lactation, in some species prolactin exerts effects on reproduction, maternal behavior, fat metabolism, immunomodulation and osmoregulation. Prolactin receptors are present in the mammary gland, hypothalamus, liver, ovary, testis, and prostate.	Lactogenic Hormone, Pituitary,Mammotropic Hormone, Pituitary,Mammotropin,PRL (Prolactin),Hormone, Pituitary Lactogenic,Hormone, Pituitary Mammotropic,Pituitary Lactogenic Hormone,Pituitary Mammotropic Hormone
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
D014599	Uterus	The hollow thick-walled muscular organ in the female PELVIS. It consists of the fundus which is the site of EMBRYO IMPLANTATION and FETAL DEVELOPMENT. Beyond the isthmus at the perineal end of fundus, is CERVIX UTERI (the neck) opening into VAGINA. Beyond the isthmi at the upper abdominal end of fundus, are the FALLOPIAN TUBES.	Fundus Uteri,Uteri,Uterine Cornua,Uterine Fundus,Uterus Cornua,Womb,Cornua, Uterine,Fundus Uterus,Fundus, Uterine,Uteri, Fundus,Wombs