oxytocin Med.
(ɒksɪˈtəʊsɪn)
[f. oxytocic a. and n. + -in1.]
A hormone present in the neurohypophysis of mammals which stimulates uterine contractions and the ejection of milk from a lactating breast and is made synthetically for use in inducing labour and controlling bleeding after delivery.
| 1928 Jrnl. Amer. Chem. Soc. Feb. 575 α-Hypophamine is being supplied under the trade name of Oxytocin..and β-Hypophamine under the trade name Vasopressin... They were first supplied for clinical use in August, 1927. 1928 Official Gaz. (U.S. Patent Office) 11 Sept. 258/1 Parke, Davis & Company, Detroit, Mich... Oxytocin for preparation for stimulating contractions of uterine and other unstriped muscular fibers. Claims use since Sept. 15, 1927. 1930 Druggists Circular Oct. 60/2 In 1928 Oliver Kamm succeeded in separating the two principles of the posterior lobe of the pituitary body. One of them, which acts upon the uterus, Kamm named oxytocin. 1937 Dispensatory U.S.A. (ed. 22) 854/1 The oxytocic principle has been called pitocin, oxytocin, [etc.]. 1965 Lee & Knowles Animal Hormones ii. 29 The second hormone, oxytocin, appears to exert its action only in mammals, but it may play some part in oviposition in the other vertebrates. 1969 Daily Tel. 19 Dec. 11/8 Oxytocin is used regularly to start or speed up a labour that is lagging. 1974 Nature 20 Dec. 630/1 Neurones in the hypothalamus synthesise the hormones vasopressin and oxytocin. 1977 ‘E. Crispin’ Glimpses of Moon xii. 256 It read like an instruction from an obstetrician to a lady who..has been given oxytocin to hurry matters up. |
Hence oxyˈtocinase [-ase], an enzyme that inactivates oxytocin.
| 1949 Chem. Abstr. XLIII. 2330 (heading) Effect of cysteine and glutathione on the oxytocinase activity of blood plasma. 1974 Passmore & Robson Compan. Med. Stud. III. ii. xl. 1/2 A serum oxytocinase which rapidly inactivates oxytocin appears in increasing amounts during pregnancy. |