Biomaterial Database

Action of rat prolactin on plasma somatomedin levels in the rat and on somatomedin release from perfused rat liver. 1977

D J Hill, and M J Francis, and R D Milner

Rat prolactin at a concentration of 50 ng/ml perfusion medium stimulated the production of somatomedin-like activity (SLA) from the perfused liver of normal rats. The effect was demonstrable in perfusions performed at 11.00 h in which rat prolactin caused a mean (+/- S.E.M.) increase in the uptake of [35S]sulphate into rat costal cartilage in vitro of 64 +/- 14% in comparison with controls, but at 15.00 h no effect was observed. No effect or rat prolactin on hypophysectomized rat liver was detectable at 11.00 h. Hypophysectomized and sham-operated rats were given five intravenous injections of 50 microgram rat prolactin or a similar volume of hormone solvent at 12 h intervals. Plasma somatomedin activity (SMA) and cartilage metabolism, measured by the uptake of radioactive sulphate and thymidine by costal cartilage in vitro, were similar in hypophysectomized animals given rat prolactin or hormone solvent. Sham-operated rats given rat prolactin showed a significant increase of plasma SMA and cartilage metabolism compared with control animals. The production of SLA by rat liver in response to rat prolactin may be related to the density of specific hepatic lactogenic receptors, since these are absent or present only in low numbers in hypophysectomized animals.

UI	MeSH Term	Description	Entries
D007016	Hypophysectomy	Surgical removal or destruction of the hypophysis, or pituitary gland. (Dorland, 28th ed)	Hypophysectomies
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
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
D002356	Cartilage	A non-vascular form of connective tissue composed of CHONDROCYTES embedded in a matrix that includes CHONDROITIN SULFATE and various types of FIBRILLAR COLLAGEN. There are three major types: HYALINE CARTILAGE; FIBROCARTILAGE; and ELASTIC CARTILAGE.	Cartilages
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
D013002	Somatomedins	Insulin-like polypeptides made by the liver and some fibroblasts and released into the blood when stimulated by SOMATOTROPIN. They cause sulfate incorporation into collagen, RNA, and DNA synthesis, which are prerequisites to cell division and growth of the organism.	Sulfation Factor,Somatomedin,Factor, Sulfation
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In