Abstract
1. The rate of release of neurohypophysial hormones in vitro, using isolated, halved neural lobes of the rat in an incubation medium containing excess K+ and Ca2+, was measured. The highest average rate of release was observed between 10 and 20 min after commencement of incubation.
2. Incubation of isolated, halved rat neural lobes in the presence of acetylcholine, with or without eserine, did not stimulate hormone release. When complete isolated hypothalamo-neurohypophysial systems were incubated in a suspension medium containing 10-7 mg/ml. acetylcholine a significant increase in the release of oxytocin occurred (P < 0·01); the increase in vasopressin release was less pronounced (P < 0·05).
3. Uptake of O2 by the isolated, halved neural lobes and the hypothalamo-neurohypophysial systems continued for 2-3 hr, i.e. in excess of the experimental incubation time.
4. During the first 40 min of incubation the control halved neural lobes increased in weight; the neural lobes incubated in buffer containing high potassium and calcium showed no increase in weight.
5. Neural lobes incubated in buffer containing excess K+ and Ca2+ contained about 3 times as much potassium as controls. The sodium content was not affected significantly.
6. Factors involved in the process of neurohypophysial hormone release are discussed.
Full text
PDF
















Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- ABRAHAMS V. C., PICKFORD M. Simultaneous observations on the rate of urine flow and spontaneous uterine movements in the dog, and their relationship to posterior lobe activity. J Physiol. 1954 Nov 29;126(2):329–346. doi: 10.1113/jphysiol.1954.sp005213. [DOI] [PMC free article] [PubMed] [Google Scholar]
- ABRAHAMS V. C., PICKFORD M. The effect of anticholinesterases injected into the supraoptic nuclei of chloralosed dogs on the release of the oxytocic factor of the posterior pituitary. J Physiol. 1956 Aug 28;133(2):330–333. doi: 10.1113/jphysiol.1956.sp005589. [DOI] [PMC free article] [PubMed] [Google Scholar]
- AMES A., 3rd, ISOM J. B., NESBETT F. B. EFFECTS OF OSMOTIC CHANGES ON WATER AND ELECTROLYTES IN NERVOUS TISSUE. J Physiol. 1965 Mar;177:246–262. doi: 10.1113/jphysiol.1965.sp007590. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ashford C. A., Dixon K. C. The effect of potassium on the glucolysis of brain tissue with reference to the Pasteur effect. Biochem J. 1935;29(1):157–168. doi: 10.1042/bj0290157. [DOI] [PMC free article] [PubMed] [Google Scholar]
- BERN H. A. The properties of neurosecretory cells. Gen Comp Endocrinol. 1962;Suppl 1:117–132. doi: 10.1016/0016-6480(62)90085-0. [DOI] [PubMed] [Google Scholar]
- BRADBURY M. W., COXON R. V. The penetration of urea into the central nervous system at high blood levels. J Physiol. 1962 Oct;163:423–435. doi: 10.1113/jphysiol.1962.sp006987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- BROWN L. M., GINSBURG M. Effect of anaesthetics and haemorrhage on the release of neurohypophysial antidiuretic hormone. Br J Pharmacol Chemother. 1956 Sep;11(3):236–244. doi: 10.1111/j.1476-5381.1956.tb01060.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Barer R., Lederis K. Ultrastructure of the rabbit neurohypophysis with special reference to the release of hormones. Z Zellforsch Mikrosk Anat. 1966;75(1):201–239. doi: 10.1007/BF00407156. [DOI] [PubMed] [Google Scholar]
- CROSS B. A., HARRIS G. W. The role of the neurohypophysis in the milk-ejection reflex. J Endocrinol. 1952 Apr;8(2):148–161. doi: 10.1677/joe.0.0080148. [DOI] [PubMed] [Google Scholar]
- DEKANSKI J. The quantitative assay of vasopressin. Br J Pharmacol Chemother. 1952 Dec;7(4):567–572. doi: 10.1111/j.1476-5381.1952.tb00723.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DOUGLAS W. W., POISNER A. M. CALCIUM MOVEMENT IN THE NEUROHYPOPHYSIS OF THE RAT AND ITS RELATION TO THE RELEASE OF VASOPRESSIN. J Physiol. 1964 Jul;172:19–30. doi: 10.1113/jphysiol.1964.sp007400. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DOUGLAS W. W., POISNER A. M. STIMULUS-SECRETION COUPLING IN A NEUROSECRETORY ORGAN: THE ROLE OF CALCIUM IN THE RELEASE OF VASOPRESSIN FROM THE NEUROHYPOPHYSIS. J Physiol. 1964 Jul;172:1–18. doi: 10.1113/jphysiol.1964.sp007399. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Daniel A. R., Lederis K. Effects of ether anaesthesia and haemorrhage on hormone storage and ultrastructure of the rat neurohypophysis. J Endocrinol. 1966 Jan;34(1):91–104. doi: 10.1677/joe.0.0340091. [DOI] [PubMed] [Google Scholar]
- Dicker S. E. Release of vasopressin and oxytocin from isolated pituitary glands of adult and new-born rats. J Physiol. 1966 Jul;185(2):429–444. doi: 10.1113/jphysiol.1966.sp007994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Douglas W. W., Ishida A. The stimulant effect of cold on vasopressin release from the neurohypophysis in vitro. J Physiol. 1965 Jul;179(1):185–191. doi: 10.1113/jphysiol.1965.sp007657. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Feldberg W., Vogt M. Acetylcholine synthesis in different regions of the central nervous system. J Physiol. 1948 Jun 25;107(3):372–381. doi: 10.1113/jphysiol.1948.sp004282. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GERSCHENFELD H. M., TRAMEZZANI J. H., DE ROBERTIS E. Ultrastructure and function in neurohypophysis of the toad. Endocrinology. 1960 May;66:741–762. doi: 10.1210/endo-66-5-741. [DOI] [PubMed] [Google Scholar]
- GINSBURG M., HELLER H. Antidiuretic activity in blood obtained from various parts of the cardiovascular system. J Endocrinol. 1953 Jul;9(3):274–282. doi: 10.1677/joe.0.0090274. [DOI] [PubMed] [Google Scholar]
- Ginsburg M., Jayasena K., Thomas P. J. The preparation and properties of porcine neurophysin and the influence of calcium on the hormone-neurophysin complex. J Physiol. 1966 May;184(2):387–401. doi: 10.1113/jphysiol.1966.sp007921. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HELLER H., LEDERIS K. Maturation of the hypothalamoneurohypophysial system. J Physiol. 1959 Sep 2;147:299–314. doi: 10.1113/jphysiol.1959.sp006244. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HODGKIN A. L., KEYNES R. D. Movements of labelled calcium in squid giant axons. J Physiol. 1957 Sep 30;138(2):253–281. doi: 10.1113/jphysiol.1957.sp005850. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HODGKIN A. L., KEYNES R. D. The potassium permeability of a giant nerve fibre. J Physiol. 1955 Apr 28;128(1):61–88. doi: 10.1113/jphysiol.1955.sp005291. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HUXLEY A. F., STAMPFLI R. Effect of potassium and sodium on resting and action potentials of single myelinated nerve fibers. J Physiol. 1951 Feb;112(3-4):496–508. doi: 10.1113/jphysiol.1951.sp004546. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Harris G. W. The excretion of an antidiuretic substance by the kidney, after electrical stimulation of the neurohypophysis in the unanaesthetized rabbit. J Physiol. 1948 Sep 30;107(4):430–435. doi: 10.1113/jphysiol.1948.sp004287. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ishikawa T., Koizumi K., Brooks C. M. Electrical activity recorded from the pituitary stalk of the cat. Am J Physiol. 1966 Mar;210(3):427–431. doi: 10.1152/ajplegacy.1966.210.3.427. [DOI] [PubMed] [Google Scholar]
- KANDEL E. R. ELECTRICAL PROPERTIES OF HYPOTHALAMIC NEUROENDOCRINE CELLS. J Gen Physiol. 1964 Mar;47:691–717. doi: 10.1085/jgp.47.4.691. [DOI] [PMC free article] [PubMed] [Google Scholar]
- KOELLE G. B. A new general concept of the neurohumoral functions of acetylcholine and acetylcholinesterase. J Pharm Pharmacol. 1962 Feb;14:65–90. doi: 10.1111/j.2042-7158.1962.tb11057.x. [DOI] [PubMed] [Google Scholar]
- KOELLE G. B. A proposed dual neurohumoral role of acetylcholine: its functions at the pre- and post-synaptic sites. Nature. 1961 Apr 15;190:208–211. doi: 10.1038/190208a0. [DOI] [PubMed] [Google Scholar]
- KOELLE G. B., GEESEY C. N. Localization of acetylcholinesterase in the neurohypophysis and its functional implications. Proc Soc Exp Biol Med. 1961 Mar;106:625–628. doi: 10.3181/00379727-106-26423. [DOI] [PubMed] [Google Scholar]
- KOIZUMI K., ISHIKAWA T., BROOKS C. M. CONTROL OF ACTIVITY OF NEURONS IN THE SUPRAOPTIC NUCLEUS. J Neurophysiol. 1964 Sep;27:878–892. doi: 10.1152/jn.1964.27.5.878. [DOI] [PubMed] [Google Scholar]
- LEDERIS K. Vasopressin and oxytocin in the mammalian hypothalamus. Gen Comp Endocrinol. 1961 Apr;1:80–89. doi: 10.1016/0016-6480(61)90027-2. [DOI] [PubMed] [Google Scholar]
- MORITA H., ISHIBASHI T., YAMASHITA S. Synaptic transmission in neurosecretory cells. Nature. 1961 Jul 8;191:183–183. doi: 10.1038/191183a0. [DOI] [PubMed] [Google Scholar]
- Mikiten T. M., Douglas W. W. Effect of calcium and other ions on vasopressin release from rat neurohypophyses stimulated electrically in vitro. Nature. 1965 Jul 17;207(994):302–302. doi: 10.1038/207302a0. [DOI] [PubMed] [Google Scholar]
- PICKFORD M., WATT J. A. A comparison of the effect of intravenous and intracarotid injections of acetylcholine in the dog. J Physiol. 1951 Jul;114(3):333–335. doi: 10.1113/jphysiol.1951.sp004625. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pickford M. The inhibitory effect of acetylcholine on water diuresis in the dog, and its pituitary transmission. J Physiol. 1939 Feb 14;95(1):226–238. doi: 10.1113/jphysiol.1939.sp003721. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SMITH M. W., THORN N. A. THE EFFECTS OF CALCIUM ON PROTEIN-BINDING AND METABOLISM OF ARGININE VASOPRESSIN IN RATS. J Endocrinol. 1965 May;32:141–151. doi: 10.1677/joe.0.0320141. [DOI] [PubMed] [Google Scholar]
- WEINSTEIN H., BERNE R. M., SACHS H. Vasopressin in blood: effect of hemorrhage. Endocrinology. 1960 May;66:712–718. doi: 10.1210/endo-66-5-712. [DOI] [PubMed] [Google Scholar]
