+ Site Statistics
+ Resolve Accession
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
Submit PDF Full TextSubmit PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Regulation of growth hormone and thyrotropin secretion by somatostatin system in rat brain

, : Regulation of growth hormone and thyrotropin secretion by somatostatin system in rat brain. Neuroendocrinology 42(3): 218-225

Somatostatin inhibits growth hormone (GH) and thyrotropin (TSH) secretion in the rat. Previous studies have shown that small discrete lesions of the periventricular hypothalamic (PV) and medial basal amygdaloid (AMG) nuclei, which contain high concentrations of somatostatin neurons, reduce somatostatin-like immunoreactivity (SLI) in the median eminence (ME) by approximately two thirds and one third, respectively. The present study assessed the function of the PV and AMG somatostatin systems in the regulation of basal episodic GH and TSH secretion. Three experiments were performed in freely behaving, chronically cannulated adult male rats. In experiment 1, bilateral electrolytic lesions (20 mC) were placed in the PV at the level of the paraventricular nucleus. In experiment 2, bilateral thermal lesions ( C .times. 1 min) were placed in the AMG. In experiment 3, thermal lesions were placed in both the PV and AMG (PV/AMG). Blood samples were removed from animals every 15 min for 5.5 h 14-21 days postoperatively. The ME was microdissected for determination of SLI content. PV, AMG and PV/ASMG lesions reduced ME SLI by 59, 26, and 91%, respectively. PV or AMG lesions had no effect on the amplitude or frequency of GH secretory peaks, GH trough levels or the total amount of GH secreted, whereas combined PV/AMG lesions reduced GH peak levels. Lesions of the AMG caused a 34% increase in mean plasma TSH levels, while PV or PV/AMG lesions reduced TSH. The latter effect was probably caused by damage to thyrotropin-releasing hormone neurons and/or axons, which are also located in the PV region. These results suggest that (1) PV and AMG somatostain systems may not have a significant role in the regulation of basal episodic GH secretion and (2) the putative AMG somatostain system exerts a significant inhibitory influence on TSH secretion.

(PDF 0-2 workdays service)

Order PDF Full Text


Click here to order any other PDF Full Text

Accession: 006288288

PDF Full Text: Submit

Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:

Other references

Colin, Jean-Paul; Hoibian, Thierry, 2003: Inventaire annote des ostracodes actuels des Departements et Territoires d'Outre mer (DOM-TOM). 3: Les ostracodes non-marins de Nouvelle-Caledonie. An annotated check-list on recent non-marine ostracodes from New Caledonia allowed the recognition of 14 genera; 10 species have been identified and 12 other kept in open nomenclature. These faunas are present in various types of biotopes: ponds a...

Perrin, Dawn R.; Bottomley, W., 1961: Pisatin: an antifungal substance from Pisum sativum L. A description is given from the Div. Plant Industry, Canberra, of some chemical and physical properties of pisatin, a phytoncide recently isolated from pea pods.

Dupuy, J. B.; Beaulieu, S.; Barden, N.; Rockford, J., 1998: Effect of chronic desipramine treatment on behavioral reactivity, sensorimotor gating and spatial memory deficits in transgenic mice with impaired type II glucocorticoid receptor function. Society for Neuroscience Abstracts 24(1-2): 958

Savchenko Ye N., 1976: New and little known palearctic crane flies diptera limoniidae part 2 subfamily eriopterinae genus molophilus. Entomological Review (English Translation of Entomologicheskoye Obozreniye) 55(2): 126-136

Franklin, David W.; Milner, Theodore E., 2003: Adaptive control of stiffness to stabilize hand position with large loads. The goal of this work was to investigate stability in relation to the magnitude and direction of forces applied by the hand. The endpoint stiffness and joint stiffness of the arm were measured during a postural task in which subjects exerted up to...

Turk Z.; Skrabalo Z., 1987: The cell interactive properties of glucosylated very low density and low density lipoproteins. Monolayered cultures of human skin fibroblasts and monocyte-derived macrophages were used to examine the high-affinity bindings, internalization and degradation of glucosylated 125I-very-low-density and 125I-low-density lipoproteins (g1c-VLDL and...

Morin, C.; Ha, B.; Olausson, H.; Marchand, S.; Ptito, A.; Pike, B.; Bushnell, M. C., 1999: Cortical representation of heat pain in hemispherectomized patients An fMRI study. Society for Neuroscience Abstracts 25(1-2): 141

Kim, J. H.; Sambor, A.; Carr, J. K.; Farhadi, A.; Fantry, L. A.; Branco, R.; Blattner, W. A.; Pombo De Oliveira, M. S., 1999: HTLV-I tax sequence variation in Rio de Janeiro Geographic differentiation of Brazilian isolates. Journal of Acquired Immune Deficiency Syndromes & Human Retrovirology 20(4): A58, April 4

Katsh, S.; Katsh, G. F.; Osher, P., 1954: Adrenal, pituitary and urinary ascorbic acid levels in rats subjected to hypothermic environment. Adult male albino rats were placed in metabolism cages and maintained at common laboratory temp. or in the cold (2-4[degree] C). When the animals were killed in their respective environments 1, 3, 10, 12 or 28 days later, the adrenal and pituitary...

Cararo, Dc; Botrel, Ta; Hills, Dj; Leverenz, Hl, 2006: Analysis of clogging in drip emitters during wastewater irrigation. The use of wastewater for crop irrigation is a practical alternative to the discharge of wastewater treatment plant effluents to surface waters. However, clogging of drip emitters is often encountered when wastewater is distributed using drip irri...