geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Tissue reactivity to hormones in larval amphibians after removal of the diencephalon


, : Tissue reactivity to hormones in larval amphibians after removal of the diencephalon. Nauchnr Dokl Vysshei Shkoly Biol Nauk 2: 72-75

Fragments of the anterior hypophyseal lobe were transplanted into abdominal cavities of control tadpoles and tadpoles with the diencephalon removed. Metamorphosis accelerated significantly in the control group, the phenomenon nearly lacking in the experimental group. The thyroid gland in the experimental group reacted to the thyrotropic principle of the adenohypophysis. A comparison of the obtained data attested to changes in the reaction level of larval tissues after removal of the diencephalon. Transplantation of a hypophyseal fragment immediately after the removal of the diencephalon into an area proximate to the supraoptic nuclei of the hypothalamus produces a strong morphogenic effect; this is promoted by a retention of a part of the neuro-secretion in the operative region. The change in reactivity of larval tissues spreads also to the thyroid gland, which reacts to the thyrotropic effect of the hypophyseal transplant. The thyroid gland hormone has but a weak metamorphosis stimulating effect after the diencephalon is removed. The reimplantation of a diencephalon in the skull cavity of a given tadpole after removal of its diencephalon significantly reduces morphogenic disturbances. Based on results of the experiments and comparison with results of previous experiments, it is concluded that removal of the diencephalon interferes with the trophic system of tissues and with their reactivity to hormones, and varies the pattern of metabolism. Metamorphosis occurs in the presence of joint functional activity of the thyroid gland, the hypophysis and the supraoptic nuclei. Exclusion of the hypothalamus produces widespread disturbances. Thyroidectomy terminated more specialized reactions, without interference with osmotic processes in the tissues and pigmentation of the mantle. Hypophysectomy arrests resorption in larval tissues, but depresses the growth of extremities and intensifies depigmentation. Apparently the retained neurosecretory nuclei are capable of maintaining the level of water metabolism. The product of nerve cells in the supraoptic area carries a multiform significance, not all the properties of which are realized in metamorphosis through the hypophysis-thyroid gland system.

US$29.90


Other references

Grasela, T.H.; Fiedler Kelly, J.B.; Salvadori, C.; Marey, C.; Jochemsen, R., 1993: Predictive performance of pre-marketing tianeptine pharmacokinetic parameters as applied to post-marketing data. Clinical Pharmacology & Therapeutics 53(2): 215

Andersch W.; Bahl H.; Gottschalk G., 1982: Acetone butanol production by clostridium acetobutylicum in an ammonium limited chemostat at low ph values. C. acetobutylicum was grown in continuous culture under ammonium limitation (15.15 mM NH+4). At a pH of 6.0 and at various dilution rates, only acetate, butyrate and ethanol were formed as nongaseous products. A decrease of the pH to values betwee...

Keglevic D.; Pongracic M., 1984: Methanolysis and aminolysis of n acetylmuramic acid lactones evidence for the retention of the d gluco configuration. Methanolysis of benzyl .alpha.-glycosides of N-acetylmuramic acid lactones with HO-6 free (2) and substituted (4, 7, 10 and 12) is catalyzed by small amounts of silica gel to give, exclusively, the corresponding methyl esters with HO-4 unsubstitut...

Darvishi Khezri, H.; Haidari Gorji, M.Ali.; Morad, A.; Gorji, H., 2014: Comparison of the antibacterial effects of matrica & Persica™ and chlorhexidine gluconate mouthwashes in mechanically ventilated ICU patients: a double blind randomized clinical trial. Accumulation of bacteria in the pharynx is one of the risk factors of pneumonia due to ventilation. One of the methods of prevention from accumulation of bacteria in the pharynx is the use of oral solutions. Chlorhexidine is considered as the gold...

Jacquillat C.; Bernard J., 1981: Detorubicin. Drugs of the Future 6(3): 139-141

McGeary, S.P.; Studen-Pavlovich, D.; Ranalli, D.N., 2002: Oral piercing in athletes: implications for general dentists. General dentists need to be aware of the growing number of athletes who display various forms of body art. Intraoral piercing and tongue jewelry place athletes at greater risk for serious medical and dental consequences that are confounded when th...

Yang, T.; Li, X.; Huang, Q.; Li, L.; Chai, Y.; Sun, L.; Wang, X.; Zhu, Y.; Wang, Z.; Huang, Z.; Li, Y.; Wu, H., 2013: Double heterozygous mutations of MITF and PAX3 result in Waardenburg syndrome with increased penetrance in pigmentary defects. Waardenburg syndrome (WS) is characterized by sensorineural hearing loss (SNHL) and pigmentary defects of the hair, skin, and iris. Heterozygous mutations of MITF and its transactivator gene PAX3 are associated with Waardenburg syndrome type II (W...

Stitzer, M.L.; Bickel, W.K.; Bigelow, G.E.; Liebson, I.A., 1986: Effect of methadone dose contingencies on urinalysis test results of polydrug-abusing methadone-maintenance patients. Drug abuse outcomes were examined during 2 contingency management procedures in which the size of the methadone dose was determined by recent urinalysis test results. Twenty polydrug-abusing methadone-maintenance patients were exposed to one of tw...

Hulter H.N.; Sigala J.F.; Sebastian A., 1981: Effects of dexamethasone on renal and systemic acid base metabolism. Long-term balance studies were performed in adrenalectomized (ADX) dogs to evaluate the effects of small amounts of a glucocorticoid steroid with minimal mineralocorticoid potency (dexamethasone; DEX) on renal and systemic acid-base metabolism und...

Amminger, G.Paul.; Schäfer, M.R., 2012: Review: limited evidence from two small trials suggests no improvement in ASD symptoms with short term ω-3 supplementation. Evidence-Based Mental Health 15(2): 51-51