Hypothalamus and endocrine function in persistent estrous rats at low environmental temperature

1960 ◽  
Vol 199 (4) ◽  
pp. 701-706 ◽  
Author(s):  
Savino A. D'Angelo
Keyword(s):  
Ascorbic Acid ◽  
Acid Concentration ◽  
Ovarian Function ◽  
Hormone Secretion ◽  
Corticosterone Level ◽  
Plasma Corticosterone ◽  
Female Rats ◽  
Endocrine Function ◽  
Ascorbic Acid Concentration ◽  
Hypothalamic Lesions

Persistent vaginal estrus with uterine and pituitary hypertrophy were found in adult female rats 4–10 months after placement of preoptic and anterior hypothalamic lesions. Serum TSH, I131 release rate and histology of the thyroid and ascorbic acid concentration of adenohypophysis, ovary and adrenal were normal. Exposure of lesioned rats to cold (5°C, 36–55 days) profoundly altered pituitary-target gland functions. Ovarian atrophy and uterine involution resulted; vaginal cornification ceased. Pituitary hypertrophy was inhibited but ascorbic acid concentration was maintained. Serum and pituitary TSH levels decreased and acceleration of thyroidal radioiodine release was prevented. Apparent dichotomy in adrenal responses developed. Despite enlarged adrenals, plasma corticosterone level in cold stressed, operated rats averaged less than one-third that of intact controls. Adrenal ascorbic acid concentration remained normal. The results underscore the basic role of central nervous mechanisms in endocrine function under chronic cold stress. Hypothalamic lesions which permit adequate trophic hormone secretion at normal temperatures drastically curtail thyroidal and ovarian function and selectively limit adrenal responses in the cold.

O3-induced inflammation in prepregnant, pregnant, and lactating rats correlates with O3 dose estimated by18O

1999 ◽  
Vol 276 (2) ◽  
pp. L332-L340 ◽  
Author(s):  
Albert F. Gunnison ◽  
Gary E. Hatch
Keyword(s):  
Ascorbic Acid ◽  
Acid Concentration ◽  
Inflammatory Responses ◽  
Virgin Female ◽  
Chemical Species ◽  
Female Rats ◽  
Acute Exposure ◽  
Physiological Status ◽  
Ascorbic Acid Concentration ◽  
Lower Lung

Previous studies have shown that rats late in pregnancy and throughout lactation are more susceptible to ozone (O3)-induced pulmonary inflammation than are prepregnant (virgin) or postlactating rats. The major aim of the present study was to determine whether these differences in response intensity could be accounted for by the O3 dose to the lower region of the lung. The relative O3 dose to the lower lung of groups of pregnant, lactating, and virgin female rats was estimated by measuring the incorporation of the18O isotope into low-speed (cells) and high-speed (surfactant) pellets of bronchoalveolar lavage fluid immediately after acute exposure to 0.5–1.1 parts/million18O3. The polymorphonuclear leukocyte (PMN) and protein inflammatory responses were established 20 h after acute exposure of identical physiological groups to 0.5–1.1 parts/million16O3(common isotope). A single regression of PMN inflammation data against surfactant 18O concentration for all physiological groups gave a linear relationship, indicating direct proportionality of PMN inflammation with this estimate of relative dose to the lower lung regardless of physiological status. This implies that the chemical species that react with surfactant molecules, i.e., O3 or its metabolites, are the same as or proportional to those chemical species responsible for initiating PMN inflammation. Additional experiments showed that lung tissue ascorbic acid concentration was significantly lower in pregnant and lactating rats than in virgin female rats. Although a causative relationship cannot be assumed, the deficit in tissue ascorbic acid concentration in pregnant and lactating rats compared with virgin female rats is consistent with their greater responsiveness and higher relative surfactant O3 dose.

The Effect of Stress and Warfarin on the Adrenal Gland in Relation to Spontaneous Hemorrhage, as Judged by Measurement of Adrenal Ascorbic Acid and Serum Corticosterone

1971 ◽  
Vol 26 (02) ◽  
pp. 275-288 ◽  
Author(s):  
S Chattopadhyay ◽  
D. D Johnson ◽  
G. J Millar ◽  
L. B Jaques
Keyword(s):  
Ascorbic Acid ◽  
Acid Concentration ◽  
Ascorbic Acid Concentration ◽  
Corticosterone Concentration ◽  
Serum Corticosterone ◽  
Spontaneous Hemorrhage ◽  
Combined Action ◽  
Series Of Experiments ◽  
Pituitary Adrenal Axis

SummaryRats were subjected to the following procedures: No treatment, Stressor (10% NaCl i.p.), Warfarin for 7 days, Stressor followed by Warfarin; and groups were sacrificed at intervals for assessment of spontaneous hemorrhage and of adrenal ascorbic acid concentration. There was no hemorrhage in the no treatment and stressor groups; some hemorrhage in the warfarin group; profound hemorrhage with Warfarin + Stressor. The adrenal ascorbic acid concentration was found to be lower, 8 h and again 5 days after stress, and remained lower in the warfarin + stress animals. Warfarin had no effect on adrenal ascorbic acid level.In another series of experiments in which the stress consisted of an electric current to the cage floor for 6 sec over 15 min, rats were sacrificed daily for determination of serum corticosterone concentration and occurrence of spontaneous hemorrhage. There was a statistically significant increase of serum corticosterone concentration with stress, warfarin and combined warfarin and stress treatments (P< 0.001 for all three variables). There was a significant correlation (r = 0.96 and 0.89, P< 0.01) for serum corticosterone concentration with hemorrhage score and incidence of hemorrhage in stressed rats receiving warfarin, but not in those receiving only warfarin. The results indicate an activation, rather than an exhaustion, of the pituitary-adrenal axis during the combined action of anticoagulant and stress, which results in the development of spontaneous hemorrhage.

Dissociation of adrenal corticosteroid production from ACTH in water-restricted female rats

1981 ◽  
Vol 241 (1) ◽  
pp. R21-R24 ◽  
Author(s):  
R. G. Doell ◽  
M. F. Dallman ◽  
R. B. Clayton ◽  
G. D. Gray ◽  
S. Levine
Keyword(s):  
Corticosterone Level ◽  
Plasma Corticosterone ◽  
Female Rats ◽  
Adrenocorticotrophic Hormone ◽  
Corticosterone Concentration ◽  
Acth Concentration

These experiments were undertaken to investigate the mechanism whereby a precipitous drop in plasma corticosterone concentration is brought about following drinking in rats on a restricted water schedule. No alteration in adrenocorticotrophic hormone (ACTH) output was found, nor was catabolism of corticosterone sufficient to account for the drop. It is concluded that corticosterone level is controlled under these conditions by a mechanism independent of ACTH concentration.

Impact of high temperature stress on ascorbic acid concentration in tomato

2018 ◽  
pp. 985-990
Author(s):  
V. Hernández ◽  
P. Hellín ◽  
J. Fenoll ◽  
M.V. Molina ◽  
I. Garrido ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
High Temperature ◽  
Temperature Stress ◽  
Acid Concentration ◽  
High Temperature Stress ◽  
Ascorbic Acid Concentration

scholarly journals Interference of ascorbic acid with chemical analytes

2005 ◽  
Vol 42 (6) ◽  
pp. 475-477 ◽  
Author(s):  
Qing H Meng ◽  
William C Irwin ◽  
Jennifer Fesser ◽  
K Lorne Massey
Keyword(s):  
Ascorbic Acid ◽  
Creatine Kinase ◽  
Uric Acid ◽  
Total Cholesterol ◽  
Acid Concentration ◽  
Total Bilirubin ◽  
Binding Capacity ◽  
Ascorbic Acid Concentration ◽  
Sodium Potassium ◽  
Creatine Kinase Mb

Background: Ascorbic acid can interfere with methodologies involving redox reactions, while comprehensive studies on main chemistry analysers have not been reported. We therefore attempted to determine the interference of ascorbic acid with analytes on the Beckman Synchron LX20®. Methods: Various concentrations of ascorbic acid were added to serum, and the serum analytes were measured on the LX20. Results: With a serum ascorbic acid concentration of 12.0 mmol/L, the values for sodium, potassium, calcium and creatinine increased by 43%, 58%, 103% and 26%, respectively ( P<0.01). With a serum ascorbic acid concentration of 12.0 mmol/L, the values for chloride, total bilirubin and uric acid decreased by 33%, 62% and 83%, respectively ( P<0.01), and were undetectable for total cholesterol, triglyceride, ammonia and lactate. There was no definite influence of ascorbic acid on analytical values for total CO2, urea, glucose, phosphate, total protein, albumin, amylase, creatine kinase, creatine kinase-MB, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total iron, unbound iron-binding capacity or magnesium. Conclusions: Ascorbic acid causes a false increase in sodium, potassium, calcium and creatinine results and a false decrease in chloride, total bilirubin, uric acid, total cholesterol, triglyceride, ammonia and lactate results.

Impacts of pulsed electric field and heat treatment on quality and sensory properties and microbial inactivation of pomegranate juice

2017 ◽  
Vol 23 (8) ◽  
pp. 668-680 ◽  
Author(s):  
Gulsun A Evrendilek
Keyword(s):  
Ascorbic Acid ◽  
Acid Concentration ◽  
Titratable Acidity ◽  
Sensory Properties ◽  
Pomegranate Juice ◽  
Total Phenolic ◽  
Anthocyanin Content ◽  
Linear Regression Models ◽  
Ascorbic Acid Concentration ◽  
Total Antioxidant

Synergistic effects of pulsed electric field+mild heat on quality properties of pomegranate juice were modeled using the best-fit multiple (non-) linear regression models with inactivation kinetics parameters of Escherichia coli O157:H7 and Staphylococcus aureus. No significant difference was detected between the control and the treated samples in terms of pH; °Brix; total antioxidant capacity; total monomeric anthocyanin content; total ascorbic acid concentration; and the sensory properties of flavor, taste, aftertaste, and overall acceptance ( p > 0.05). An exposure of 65.3 J and 40 ℃ caused an increase on conductivity; titratable acidity; L*, a*, and b* values; and a decrease of browning index, total phenolic content, total antioxidant capacity, total monomeric anthocyanin content, total ascorbic acid concentration, and in the sensory properties of color and sourness in pomegranate juice. The goodness-of-fit for the best-fit multiple (non-) linear regression models in descending order belonged to E. coli O157:H7 (92.98%), S. aureus (84.06%), color a* (83.9%), titratable acidity (81.3%), color L* (78.5%), color b* (78.3%), conductivity (74.8%), total phenolic content (74.1%), and total ascorbic acid concentration (64.74%), respectively. De and ze values for E. coli O157:H7 and S. aureus ranged from 105.64 to 1093.25 and from 79.18 to 1057.73 µs with 27.39 and 30.80 J, consequently.

scholarly journals Determination of Ascorbic Acid Concentration of Some Commercial Fruits Juices Sold in Ugbokolo Benue State, Nigeria

2017 ◽  
Vol 3 (1) ◽  
pp. 19-22
Author(s):  
Fabian Audu Ugbe ◽  
Victoria Abiola Ikudayisi ◽  
Oluwagbemiga Tayo Amusan
Keyword(s):  
Ascorbic Acid ◽  
Vitamin C ◽  
Dietary Intake ◽  
Pregnant Women ◽  
Acid Concentration ◽  
Ascorbic Acid Concentration ◽  
Titrimetric Method

This research was aimed at investigating the concentration of Ascorbic Acid (Vitamin C) in some commercial fruits juices: ‘5’ Alive, Hollandia yoghurt, Nutri milk, Ribena, Lacasera, Happy hour, Viju milk, Chi exotic and Chi vita sold in Ugbokolo, Benue State, Nigeria by titrimetric method using 2,6-dichlorophenolindophenol (DCPIP) as titrant. The ascorbic acid (AA) content in milligram per 100ml of the various juices investigated is in the order: ‘5’ Alive (11.25) > Ribena (5.47) > nutri milk (5.31) > Happy hour (4.38) > Hollandia yoghurt (1.25) > Lacasera (0.47) ≈ Chi exotic (0.47) >Viju milk (0.31) > Chi vita (0.16). It was observed that half a litre of ‘5’ Alive (56.25 mg AA) a day is suitable for adults and pregnant women, a liter each of Ribena  (54.70 mg AA) and Nutri milk (53.10 mg AA) per day for adults, while a litre of Happy hour (43.80 mg AA) per day is suitable for adolescents. It can be concluded that commercial fruits juices when taken in large amount will add to the daily human dietary intake of the vitamin.

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