INITIALE VERTEILUNG VON RADIO-C IN UNREIFEN RATTEN NACH INFUSION PHYSIOLOGISCHER MENGEN VON TESTOSTERON-4-14C

1967 ◽  
Vol 54 (3) ◽  
pp. 557-567 ◽  
Author(s):  
K.-O. Mosebach ◽  
H. Jühe ◽  
W. Dirscherl
Keyword(s):  
Specific Activity ◽  
Male Rats ◽  
Injection Technique ◽  
Sprague Dawley ◽  
Immature Male ◽  
Target Organs ◽  
Sprague Dawley Rats ◽  
Specific Activities ◽  
Infusion Technique ◽  
Vesicle Secretion

ABSTRACT Over a period of 2 hours the distribution and the specific activities of 14C (dpm/mg C) in organs of immature male Sprague-Dawley rats were studied after infusion of testosterone-4-14C. Only in liver, adrenals, kidneys and lungs we found specific activities essentially higher than those of the blood. The values of testis, seminal vesicles, prostata, epididymis and penis were similar to blood. Corresponding to former experiments using injection technique the more physiological infusion technique did not show any accumulation of radioactivity in the target organs too. On the contrary the specific activity of the seminal vesicle secretion was clearly higher than those of the residue organ and the blood. In adrenals medulla contained more radioactivity than cortex, demonstrated by 3 different methods (combustion, extraction and histoautoradiography). The distributions of progesterone-4-14C and oestradiol-4-14C after infusion in immature male rats were similar to those of testosterone-4-14C. The latter did not show a striking affinity for uterus, vagina and ovaries after infusion into female immature rats.

SERUM 5α-ANDROSTANE-3α,17β-DIOL, ANDROSTERONE AND TESTOSTERONE CONCENTRATIONS IN THE IMMATURE MALE RAT: INFLUENCE OF TIME OF DAY

1977 ◽  
Vol 75 (1) ◽  
pp. 177-178 ◽  
Author(s):  
W. H. MOGER ◽  
P. R. MURPHY
Keyword(s):  
Serum Testosterone ◽  
Temporal Variations ◽  
Time Of Day ◽  
Male Rats ◽  
Male Rat ◽  
Sprague Dawley ◽  
Circadian Variations ◽  
Adult Rat ◽  
Immature Male ◽  
Sprague Dawley Rats

Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada, B3H 4H7 (Received 22 April 1977) The concentration of testosterone in the serum of the adult rat varies significantly over a 24 h period (Kinson & Lui, 1973; Howland, 1975; Wilson, McMillan, Seal & Ahmed, 1976). However, studies on circadian variations in serum testosterone concentrations in immature male rats have yielded conflicting results. Grotjan & Johnson (1976) reported significant changes with time in 25–26-day-old Holtzman rats, whereas Döhler & Wuttke (1976) did not observe significant changes in 13–18 or 25–30-day-old Sprague–Dawley rats maintained on the same lighting schedule (14 h light: 10 h darkness). Recently we reported that from 20–35 days of age, 5α-androstane-3α,17β-diol (androstanediol) is the predominant androgen in the circulation of male rats (Moger, 1977). This study was undertaken to determine temporal variations in the concentrations of androstanediol, androsterone and testosterone. Forty-nine male Sprague

scholarly journals THE Ah PHENOTYPE. SURVEY OF FORTY-EIGHT RAT STRAINS AND TWENTY INBRED MOUSE STRAINS

Genetics ◽  
1982 ◽  
Vol 100 (1) ◽  
pp. 79-87
Author(s):  
Daniel W Nebert ◽  
Nancy M Jensen ◽  
Hisashi Shinozuka ◽  
Heinz W Kunz ◽  
Thomas J Gill
Keyword(s):  
Specific Activity ◽  
Inbred Mouse ◽  
Inbred Mouse Strain ◽  
Mouse Strains ◽  
Ah Receptor ◽  
Inbred Mouse Strains ◽  
Sprague Dawley ◽  
Rat Strains ◽  
Specific Activities ◽  
Inbred Rat

ABSTRACT Forty-four inbred and four randombred rat strains and 20 inbred mouse strains were examined for their Ah phenotype by determining the induction of liver microsomal aryl hydrocarbon (benzo[a]pyrene) hydroxylase activity (EC 1.14.14.1) by intraperitoneal treatment with either β-naphthoflavone or 3-methylcholanthrene. All 48 rat strains were found to be Ah-responsive. The maximally induced hydroxylase specific activities of the ALB/Pit, MNR/Pit, MR/Pit, SHR/Pit, and Sprague-Dawley strains were of the same order of magnitude as the basal hydroxylase specific activities of the ACI/Pit, F344/Pit, OKA/Pit, and MNR/N strains. Six of the 20 mouse strains were Ah-nonresponsive (i.e. lacking the normal induction response and presumably lacking detectable amounts of the Ah receptor). The basal hydroxylase specific activities of the BDL/N, NFS/N, STAR/N, and ST/JN mouse strains were more than twice as high as the maximally induced hydroxylase specific activity of the CBA/HT strain.——To date, 24 Ah-nonresponsive mouse strains have been identified, out of a total of 68 known to have been characterized. The reasons for not finding a single Ah-nonresponsive inbred rat strain—as compared with about one Ah-nonresponsive inbred mouse strain found for every three examined—remain unknown.

scholarly journals Erythropoietin Produces a Dual Effect on Carotid Body Chemoreception in Male Rats

2021 ◽  
Vol 12 ◽  
Author(s):  
Christian Arias-Reyes ◽  
Sofien Laouafa ◽  
Natalia Zubieta-DeUrioste ◽  
Vincent Joseph ◽  
Aida Bairam ◽  
...  
Keyword(s):  
Carotid Body ◽  
No Synthase ◽  
Male Rats ◽  
High Dose ◽  
No Production ◽  
Sprague Dawley ◽  
En Bloc ◽  
No Synthase Inhibitor ◽  
Sprague Dawley Rats ◽  
Synthase Inhibitor

Erythropoietin (EPO) regulates respiration under conditions of normoxia and hypoxia through interaction with the respiratory centers of the brainstem. Here we investigate the dose-dependent impact of EPO in the CB response to hypoxia and hypercapnia. We show, in isolated “en bloc” carotid body (CB) preparations containing the carotid sinus nerve (CSN) from adult male Sprague Dawley rats, that EPO acts as a stimulator of CSN activity in response to hypoxia at concentrations below 0.5 IU/ml. Under hypercapnic conditions, EPO did not influence the CSN response. EPO concentrations above 0.5 IU/ml decreased the response of the CSN to both hypoxia and hypercapnia, reaching complete inhibition at 2 IU/ml. The inhibitory action of high-dose EPO on the CSN activity might result from an increase in nitric oxide (NO) production. Accordingly, CB preparations were incubated with 2 IU/ml EPO and the unspecific NO synthase inhibitor (L-NAME), or the neuronal-specific NO synthase inhibitor (7NI). Both NO inhibitors fully restored the CSN activity in response to hypoxia and hypercapnia in presence of EPO. Our results show that EPO activates the CB response to hypoxia when its concentration does not exceed the threshold at which NO inhibitors masks EPO’s action.

Effects of androgens on bioactivity and immunoreactivity of pituitary FSH in GnRH antagonist-treated male rats

1990 ◽  
Vol 122 (2) ◽  
pp. 168-174 ◽  
Author(s):  
Om P. Sharma ◽  
Shafiq A. Khan ◽  
Gerhard F. Weinbauer ◽  
Mohammed Arslan ◽  
Eberhard Nieschlag
Keyword(s):  
Isoelectric Focusing ◽  
Gnrh Antagonist ◽  
Molecular Composition ◽  
Male Rats ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Combined Administration ◽  
Ph Range ◽  
Fsh Bioactivity

Abstract The effects of androgens on the bioactivity and molecular composition of pituitary FSH were examined in intact and GnRH antagonist-suppressed male rats. Eight groups of adult Sprague-Dawley rats were subjected to the following treatments: antagonist (75 μg/day by osmotic minipumps; sc), testosterone-filled Silastic implants (3×5 cm, sc), dihydrotestosterone-filled Silastic implants (3×5 cm, sc), E2 benzoate (15 μg/day, sc), and combined administration of antagonist with either steroid for 3 weeks. At the end of the treatment period, pituitaries were dissected out and homogenised. FSH content was determined in the pituitary extracts by an in vitro bioassay and a radioimmunoassay. Individual pituitary extracts from rats treated with vehicle, testosterone and testosterone + antagonist were subjected to isoelectric-focusing on sucrose density gradients performed in the pH range from 3.5 to 7.0. Individual isoelectric-focusing fractions (100-120) were analysed for bioactive and immunoreactive FSH. Treatment with antagonist, E2 or antagonist + E2 caused a significant decrease in pituitary FSH, whereas testosterone and dihydrotesterone alone or in combination with antagonist prevented the decrease in pituitary FSH. The effects of all treatments on both bioactive and immunoreactive FSH were similar. Testosterone treatment not only maintained FSH synthesis but also altered the molecular composition of pituitary FSH. Following treatment with testosterone there was a shift of maximal FSH bioactivity to the more acidic pH range. On the other hand, less bioactivity was recovered than corresponding immunoreactivity in the higher pH region, resulting in significantly reduced ratios of bioactivity to immunoreactivity of FSH. No significant differences were found in the isoelectric-focusing profiles or bioactivity to immunoreactivity ratios of pituitary FSH in animals treated with testosterone alone or in combination with antagonist. The results demonstrate that testosterone not only maintained the synthesis of both bioactive and immunoreactive FSH in male rats, but also influences the molecular composition of pituitary FSH. These effects of testosterone on pituitary FSH appear not to be mediated through hypothalamic GnRH.

Repeated restraint stress upregulates rat sulfotransferase 1A1

2018 ◽  
Vol 30 (2) ◽  
pp. 265-273
Author(s):  
Rajiv Balyan ◽  
Ma Cai ◽  
Wenhong Zhao ◽  
Zhao Dai ◽  
Yujia Zhai ◽  
...  
Keyword(s):  
Restraint Stress ◽  
Biological Activities ◽  
Male Rats ◽  
Transcriptional Level ◽  
Sprague Dawley ◽  
Metabolizing Enzymes ◽  
Sprague Dawley Rats ◽  
Repeated Restraint Stress ◽  
Enhanced Expression ◽  
Hormone Homeostasis

Abstract BackgroundSulfotransferases (SULTs) are phase II drug-metabolizing enzymes. SULTs also regulate the biological activities of biological signaling molecules, such as various hormones, bile acids, and monoamine neurotransmitters; therefore, they play critical roles in the endocrine and nervous systems. People are subject to various kinds of physical, chemical, toxicological, physiological, and psychological stresses at one time or another. The study of the effects produced by stress may lead to finding novel remedies for many disease conditions. The effect of repeated restraint stress on rat SULT expression has not been studied. MethodsThis study involves the effect of repeated restraint stress on SULT1A1 expressions. Male Sprague-Dawley rats (n=4) were subjected to repeated restraint stress 2 h/day for 7 days. Protein and RNA expression of SULT1A1 were analyzed by western blot and quantitative real time reverse transcription polymerase chain reaction, respectively, in important tissues. ResultsWe observed that repeated restraint stress increased the expression of SULT1A1 in the liver, adrenal glands, cerebellum, hypothalamus, and cerebral cortex in male rats. Patterns of enhanced expression were observed at both mRNA and protein level, indicating that repeated restraint stress stimulates enzyme expression at the transcriptional level. ConclusionsChanges of SULT1A1 expression in important tissues caused by repeated restraint stress will have a significant effect on drug metabolism and xenobiotics detoxification. The significant changes in endocrine glands and brain sections may also cause disturbances in hormone homeostasis, therefore leading to disease conditions. This report provides clues for the understanding of the effect of stresses on health.

scholarly journals THE EFFECT OF SECANG EXTRACT (CAESALPINIA SAPPAN LINN) ON THE WEIGHT AND HISTOLOGY APPEARANCE OF WHITE MALE RATS’ HEARTS INDUCED BY ISOPROTERENOL

2017 ◽  
Vol 9 ◽  
pp. 59
Author(s):  
Kristiana Nugraheni ◽  
Fadlina Chany Saputri
Keyword(s):  
Myocardial Infarction ◽  
Body Weight ◽  
White Male ◽  
Negative Control ◽  
Male Rats ◽  
Heart Cells ◽  
Sprague Dawley ◽  
Macroscopic Appearance ◽  
Caesalpinia Sappan ◽  
Sprague Dawley Rats

Objective: This study was conducted to determine the cardioprotective effect of secang extract on the heart cells of rats who suffered from myocardialinfarction induced by isoproterenol.Materials and Methods: Sprague Dawley rats were divided into six groups: Normal control, negative control, control extract (200 mg/kg), and threedifferent dose extract groups (50, 100, and 200 mg/kg body weight) that were given treatment for 30 days, and then, induced with isoproterenol.Observations were made for changes in the macroscopic appearance, cardiac weight, and histology of the cardiac organ.Results: The results showed a decrease in the incidence of myocardial infarction in rats given secang extract. The infarction area decreased withincreasing doses of extract. The weight of the heart in the control extract group was smaller than in the negative control group.Conclusions: Damage to heart cells, seen in the microscope, decreased with increasing doses.

scholarly journals Expression and specific activities of carbamoyl phosphate synthetase 1 in chronic hypoxic rats

2016 ◽  
Vol 25 (1) ◽  
pp. 3-9
Author(s):  
Uly A. Nikmah ◽  
Ani R. Prijanti ◽  
Sri W.A. Jusman ◽  
Mohamad Sadikin
Keyword(s):  
Specific Activity ◽  
Aerobic Condition ◽  
Hypoxic Condition ◽  
Total Body Weight ◽  
Enzymatic Activities ◽  
Carbamoyl Phosphate Synthetase ◽  
Sprague Dawley ◽  
Carbamoyl Phosphate ◽  
Carbamoyl Phosphate Synthetase 1 ◽  
Specific Activities

Background: Urea biosynthesis is a very important process in the liver which needs ATP, CO2 and functional mitochondria or aerobic condition. Liver can adapt to hypoxic condition, generally and locally. This study aimed to analyze the effect of chronic hypoxia on liver urea biosynthesis as indicated by the level and specific activity of mRNA of carbamoyl phosphate synthetase 1 (CPS1), a key enzyme in urea biosynthesis in hypoxic rats.Methods: 20 male Sprague-Dawley rats were placed in hypoxic chamber supplied by a mixture of 10% O2 and 90% N2. Five rats were sacrificed at 1, 3, 5, and 7 days after exposure. Liver homogenates were analyzed for HIF-1 (hypoxia inducible factor-1) by ELISA, CPS1 mRNA by real time RT-PCR and CPS1 enzymatic specific activities by Pierson method. Data were analyzed by ANOVA test and Pearson correlation.Results: The HIF-1 in liver increased significantly, as well as CPS1 mRNA and CPS1 enzymatic activities (p<0.05). There was a strong correlation (r=0.618; p<0.01) between the level of CPS1 mRNA and CPS1 enzymatic activities, moderate correlation between HIF-1 and CPS1 mRNA (r=0.419; p<0.05) but no correlation between HIF-1 and CPS1 enzymatic activities. The study indicated that urea biosynthesis in liver was affected by hypoxia and partially under HIF-1 regulation. The study also found increase of urea and NH3 biosynthesis related to proteolysis as indicated by the decrease of total body weight and liver weight.Conclusion: There was an increase in the expression and specific activities of CPS1 in urea biosynthesis as a result of increasing proteolysis  in chronic hypoxic condition.

scholarly journals Destruction of Immature Erythrocytes Measured by Bilirubin Excretion

Blood ◽  
1969 ◽  
Vol 33 (5) ◽  
pp. 717-726
Author(s):  
KIYOYASU NAGAI ◽  
EIZO KAKISHITA
Keyword(s):  
Normal State ◽  
General Circulation ◽  
Direct Evidence ◽  
Specific Activity ◽  
Total Radioactivity ◽  
Sprague Dawley ◽  
Wistar Strain ◽  
Bilirubin Excretion ◽  
Sprague Dawley Rats ◽  
Bile Fistula

Abstract The change in radioactivity of bilirubin with time was measured after injection of glycine 2-14C into rats with a bile fistula. The total radioactivity and specific activity of bilirubin were abnormally high in rats of which erythropoiesis was increased following hemorrhage. When the newly formed erythrocytes labeled with glycine 2-14C in the peak of reticulocytosis were transfused into rats with a bile fistula, the excretion of labeled bilirubin increased rapidly. The amount of newly formed erythrocytes destroyed within 7 days after transfusion into normal animals was calculated as 4.4 per cent of the total erythrocytes formed during maximum reticulocytosis and 1.1 per cent of those formed in the normal state in Sprague Dawley rats, while in the Wistar strain, the values were 13.4 per cent and 2.2 per cent, respectively. These results provide direct evidence for increased production of short-lived erythrocytes during enhanced erythropoiesis, and the hemolysis of newly formed erythrocytes soon after they reach the general circulation may contribute to the production of shunt bilirubin.

In vivo leucine oxidation at rest and during two intensities of exercise

1982 ◽  
Vol 53 (4) ◽  
pp. 947-954 ◽  
Author(s):  
P. W. Lemon ◽  
F. J. Nagle ◽  
J. P. Mullin ◽  
N. J. Benevenga
Keyword(s):  
Skeletal Muscle ◽  
Specific Activity ◽  
Muscle Metabolism ◽  
Weighted Average ◽  
Mixed Diet ◽  
Sprague Dawley ◽  
Tracer Dose ◽  
Sprague Dawley Rats ◽  
14Co2 Production

After ingestion of a mixed diet containing a tracer dose (10 muCi) of L-[1–14C]leucine (Leu), 32 male Sprague-Dawley rats (70–90 g) remained at rest (R) or completed 1 h exercise at 80 (E80) or 40% VO2max (E40). 14CO2 production was assessed for 6 h (exercise occurred from h 2 to 3). Four rats were killed at 2, 3, 4, and 6 h (R), at 3 and 6 h (E80), and at 6 h (E40). Determinations were 1) tissue specific activity dpm X mumol-1 from a) mixed skeletal muscle (gastrocnemius, soleus, quadriceps, and hamstrings) and b) liver and 2) radioactivity remaining in the gastrointestinal tract (GIT). Leu oxidized (mumol) was estimated (14 CO2 dpm X tissue sp act dpm-1 X mumol-1) independently from skeletal muscle and liver. Results were 1) 14CO2 production increased in both E80 and E40 compared with R (P less than 0.05), 2) E80 14CO2 increase was greater than E40 (P less than 0.05), 3) GIT absorption was reduced in E80 and E40 compared with R (P less than 0.05), and 4) exercise Leu oxidation (weighted average of tissue estimates) was 26% greater than R (P less than 0.05). The origin and site of the increased Leu oxidation cannot be determined from the present data; however, due to the magnitude of increase in skeletal muscle metabolism relative to other tissues during exercise, it is probable that skeletal muscle plays a significant role.

Distribution of cyclic AMP phosphodiesterase in adipose tissue from trained rats

1986 ◽  
Vol 61 (4) ◽  
pp. 1546-1551 ◽  
Author(s):  
K. A. Kenno ◽  
J. L. Durstine ◽  
R. E. Shepherd
Keyword(s):  
Cyclic Amp ◽  
Specific Activity ◽  
Particulate Fraction ◽  
Fat Cells ◽  
Isolated Fat Cells ◽  
Sprague Dawley ◽  
Enzyme Form ◽  
Cyclic Amp Phosphodiesterase ◽  
Sprague Dawley Rats ◽  
Michaelis Constants

Fat cells were isolated from sedentary and exercise trained female Sprague-Dawley rats and cyclic AMP phosphodiesterase (cyclic AMP-PDE) activities were determined from crude homogenates of the fat cells in the whole homogenate, P5, P48, and S48 fractions. Exercise training resulted in a significant increase in the mean specific activity of cyclic AMP-PDE (pmol X min-1 X mg-1) from the whole homogenate and S48 fraction at cyclic AMP concentrations of 4, 8, and 16 microM and in the P48 fraction at 8 and 16 microM cyclic AMP. Cyclic AMP-PDE kinetic plots according to Lineweaver-Burk for the calculation of Michaelis constants (Km) and maximum enzyme velocities (Vmax) were nonlinear, indicating both a low and high enzyme form. The Michaelis constants were significantly lower in trained rats than those of its control for the high Km form of cyclic AMP-PDE in the whole and soluble fractions and for the low Km form of the P5 particulate fraction. The Vmax of the high Km form of the P48 particulate fraction from trained animals was also significantly higher than that found in its control. Phosphodiesterase inhibition by methylxanthines in the various fractions was similar in both trained and sedentary animals. These changes in specific activity, Michaelis constants, and Vmax of cyclic AMP-PDE from crude homogenates of isolated fat cells from exercise trained animals may account for the decreased intracellular levels of cyclic AMP following catecholamine stimulation of isolated fat cells from trained rats.

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