Non-invasive measurement of adrenocortical activity in male and female rats

2007 ◽  
Vol 41 (3) ◽  
pp. 372-387 ◽  
Author(s):  
M Lepschy ◽  
C Touma ◽  
R Hruby ◽  
R Palme
Keyword(s):  
High Performance ◽  
Time Course ◽  
Small Body ◽  
Challenge Test ◽  
General Information ◽  
Female Rats ◽  
Invasive Technique ◽  
Adrenocortical Activity ◽  
Non Invasive ◽  
Male And Female Rats

Rats are widely used in biomedical research as animal models for human diseases. However, due to their small body size, blood sampling is complicated and invasive and thereby can seriously interfere with endocrine functions and possibly compromise the animals' welfare. Therefore, a non-invasive technique to monitor stress hormones in these animals is highly desired. Our study aimed to gain general information about corticosterone metabolism and excretion and to validate a 5 α-pregnane-3 β,11 β,21-triol-20-one enzyme immunoassay (EIA) to reliably measure faecal corticosterone metabolites (CMs) in laboratory rats. In total, 18 rats were administered 2.3 MBq of 3H-corticosterone intravenously and per os, respectively (intravenous: 6 males and 6 females; per os: 3 males and 3 females). Subsequently, all voided excreta were frequently collected for five days. About 75±9% of the recovered CMs were found in the faeces. Peak concentrations of radiolabelled steroids appeared in the urine after 1.7±0.6 h in males and after 6.0±3.5 h in females. In faeces, maxima were observed after 14.7±2.4 h in both sexes. In principle, the time course and delay for both routes of administration (intravenous or per os) were the same, except for a delay of peak concentrations in urine (4.5±2.1 h) in per os administered males. Using high-performance liquid chromatography (HPLC), faecal 3H-CMs were characterized and differences were found between the sexes. In both sexes, corticosterone was extensively metabolized, but while males showed only minor variations in their CM patterns, those of females differed largely between individuals. To validate the mentioned EIA, we investigated the diurnal variation (DV) of glucocorticoids as well as effects of the injection procedure itself and conducted an adrenocorticotropic hormone challenge test and a dexamethasone suppression test, using six male and six female rats each. Our results demonstrated that pharmacological stimulation, suppression and DV of adrenocortical activity were accurately reflected by means of CM measurement in faeces. By successful physiological validation, we proved for the first time the suitability of an immunoassay to non-invasively monitor adrenocortical activity in rats of both sexes. This method opens up new perspectives for biomedical and pharmacological investigations as well as for animal welfare related issues.

Sex Differences of Hepatic Conjugation of Bilirubin Determine its Maximal Biliary Excretion in Non-Anaesthetized Male and Female Rats

1983 ◽  
Vol 64 (1) ◽  
pp. 85-90 ◽  
Author(s):  
Maurizio Muraca ◽  
Jan De Groote ◽  
Johan Fevery
Keyword(s):  
Biliary Excretion ◽  
High Performance ◽  
Relative Proportion ◽  
Female Rats ◽  
Male Rats ◽  
Transferase Activity ◽  
Hepatic Transport ◽  
Male And Female Rats ◽  
Udp Glucuronosyltransferase ◽  
Rate Limiting

1. Hepatic bilirubin UDP-glucuronosyltransferase activity was higher in female than in male rats; gonadectomy decreased enzyme activity in females and increased it in males. This sex difference in bilirubin conjugation was further used to evaluate the effect of differences in conjugation on the maximal biliary excretion of bilirubin in the non-anaesthetized rat. 2. After infusion of bilirubin, the maximal biliary excretory rate (Tm) and maximal concentration of bilirubin in bile were respectively 70% and 40% higher in female than in male rats; these values were decreased in females after ovariectomy and increased in males after orchiectomy. A linear relationship was found (r = 0.86; P < 0.001) between bilirubin Tm and hepatic bilirubin UDP-glucuronosyltransferase activity in the four groups of rats, suggesting that conjugation was the rate-limiting step for the maximal hepatic transport of bilirubin. 3. At the end of bilirubin infusion, bilirubin conjugates in serum, determined by alkaline methanolysis and high-performance liquid chromatography, ranged from 0.5 to 1.4% of total bilirubin. Therefore no significant reflux of conjugated bilirubin occurred during saturation of the hepatic transport of the pigment, once more suggesting that the secretory step was not rate-limiting. 4. The composition of bilirubin conjugates in bile was similar in the four groups of rats, despite significant differences in transferase activity. This suggests that the relative proportion of bilirubin mono- and di-conjugates in bile is affected by factors other than transferase activity alone. Relatively more monoconjugates were excreted under the bilirubin load than in basal conditions.

scholarly journals Clinical relevance of combining Thermography with Nailfold Capillaroscopy to improve differentiation between primary and secondary Raynaud’s Phenomenon

2021 ◽  
pp. 39-48
Author(s):  
Yumiko Vreeburg ◽  
Laura van Vugt ◽  
Sabrina Simonnet ◽  
Daphne Valk ◽  
Gus Schardijn ◽  
...  
Keyword(s):  
Cardiovascular Disease ◽  
Vascular Function ◽  
Raynaud’S Phenomenon ◽  
Challenge Test ◽  
Raynaud's Phenomenon ◽  
Nailfold Capillaroscopy ◽  
Invasive Technique ◽  
Microvascular Damage ◽  
Non Invasive ◽  
Age Related

Objectives: Early microvascular damage and dysfunction are clinically mirrored in Raynaud’s phenomenon (RP). Currently, nailfold capillaroscopy (NC) is applied to differentiate between primary RP (PRP) and secondary RP (PRP), associated with connective tissue disease. However, abnormal morphology can also be caused due to age-related changes and cardiovascular disease. Thermography (TG) is a non-invasive technique which enables quantification of cutaneous vascular function. An approach using both NC and TG could improve the differentiation between PRP and SRP. Methods: Thirty RP patients (PRP, n = 21; SRP, n = 9) underwent nailfold capillaroscopy and thermography. Morphologic features were scored and patients were categorized according to the guidelines of EULAR Study group on Microcirculation in Rheumatic Diseases. TG of the hand was performed before, directly and ten minutes after a cold challenge test. Baseline images and rewarming curves were analyzed. Results: Capillary abnormalities with NC were found in all SRP patients (9/9) and in 48% (10/21) of PRP patients. Out of 10 PRP patients with altered capillary morphology, 9 (90%) had a cardiovascular disease. For all patients mean temperature was significantly higher 10 minutes after cold induction than before (p < 0,01). The gradient of the rewarming curve was significantly lower in patients with SRP compared to PRP patients (p = 0.015). Conclusions: Nailfold capillaroscopy and thermography can reliably be used to measure microvascular damage and dysfunction. Additional thermography can assist in differentiating between PRP and SRP, especially in elderly patients or in presence of a cardiovascular disease. Keywords: Raynaud’s phenomenon; Nailfold capillaroscopy; Thermography

Physiological validation of a non-invasive method to evaluate adrenocortical activity and the time course for the excretion of stress hormones in the feces of three species of desert gerbils

2019 ◽  
Vol 65 (1-2) ◽  
pp. 21-27 ◽  
Author(s):  
Justin R. St. Juliana ◽  
Jocelyn L. Bryant ◽  
Nadja Wielebnowski ◽  
Burt P. Kotler
Keyword(s):  
Stress Responses ◽  
Time Course ◽  
Adrenocorticotropic Hormone ◽  
Stress Hormones ◽  
Adrenocortical Activity ◽  
Non Invasive ◽  
Fecal Glucocorticoid Metabolites ◽  
Desert Rodents ◽  
Invasive Method ◽  
Time Frames

We evaluated the suitability of a corticosterone enzyme immunoassay (EIA) to monitor excretion of fecal glucocorticoid metabolites (FGM) in response to Adrenocorticotropic hormone (ACTH) and saline injections in three desert rodent species (Gerbillus andersoni allenbyi (GA), Gerbillus nanus (GN), and Gerbilis piridium (GP). We exposed 24 gerbils (N = 9 for GA, N = 7 for GN, N = 8 for GP) to an ACTH and a saline injection at different times. Fecal samples were collected hourly for 24 hours after injection. The average starting concentration (baseline) FGM concentration was 797 ng/g for GA, 183 ng/g for GN, and 749 ng/g for GP. The average peak concentration was 2377 ng/g for GA, 589 ng/g for GN, and 1987 ng/g for GP. We were able to provide a physiological validation for the chosen assay in GAs and GPs, however, our results for GNs were less clear. We found an increase in FGM concentrations on average after 5.5 hours in GA, 3.1 hours in GN, and 3.8 hours in GP. We found a peak in FGM concentration on average after 8.8 hours in GA, 5.6 hours in GN, and 10.3 hours in GP. We determined that FGM concentration returned to starting value on average after 14.4 hours in GA, 9.1 hours in GN, and 15.1 hours in GP. The outcomes of this study can help establish trapping protocols and time frames for FGM monitoring of these wild small mammal populations. The time course for excretion of FGM is similar between the species in this study, and comparable to some non-desert rodents. We found high variation in the time course of excretion within species. This variation needs to be taken into account when monitoring stress responses in the field. By assessing adrenocortical activity using FGM monitoring, stress responses to varying ecological and environmental factors can be reliably examined in the field.

scholarly journals Isolation and Quantification of Sphingosine and Sphinganine from Rat Serum Revealed Gender Differences

Biomolecules ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 459 ◽  
Author(s):  
Graham Brogden ◽  
Diab M. Husein ◽  
Pablo Steinberg ◽  
Hassan Y. Naim
Keyword(s):  
High Performance ◽  
Gene Mutations ◽  
Female Rats ◽  
Sphingolipid Metabolism ◽  
Female Rat ◽  
Serum Samples ◽  
Fluorescence Detector ◽  
Rat Serum ◽  
Male And Female Rats ◽  
Significant Difference

Sphingolipids are an important group of lipids that play crucial roles in living cells, facilitating cell recognition, signal transduction and endocytosis. The concentration of sphingosine and some of its derivatives like sphinganine may serve as a biomarker for the diagnosis of sphingolipidoses or be used for further research into similar diseases. In this study, a sphingolipid extraction and a high resolution detection method specific for sphingosine and sphinganine was adapted and tested. Lipids were extracted from rats’ serum, coupled to o-phthalaldehyde and detected with a fluorescence detector after running through a silica gel column in a high performance liquid chromatography system. With this method, we analysed 20 male and 20 female rat serum samples and compared the concentrations of sphingosine and sphinganine. The results showed a significant difference between the sphingosine concentrations in the male and female rats. The sphingosine concentration in female rats was 805 ng/mL (standard deviation, SD ± 549), while that in males was significantly lower at (75 ng/mL (SD ± 40)). Furthermore, the sphingosine:sphinganine ratio was almost 15-fold higher in the females’ samples. The method presented here facilitates the accurate quantification of sphingosine and sphinganine concentrations down to 2.6 ng and 3.0 ng, respectively, and their ratio in small amounts of rat serum samples to study the sphingolipid metabolism and its potential modulation due to gene mutations or the effect of prevalent toxins.

scholarly journals Gastrin, Histamine Prostaglandin: Indicators for assessing efficacy of cimetidine, Omeprazole and Ranitidine in Gastric Ulcer Treatment

2018 ◽  
Vol 5 (2) ◽  
pp. 5-12
Author(s):  
Jimmy Etukudo Okon ◽  
Gideon Umezuruike Egesie
Keyword(s):  
Gastric Ulcer ◽  
High Performance ◽  
Female Rats ◽  
Albino Rats ◽  
Radical Cure ◽  
Male And Female ◽  
Ulcer Disease ◽  
Male And Female Rats ◽  
Significant Difference ◽  
Organ Specific

Background and Objectives: There is increase prevalence of gastric ulcer in the society, but the drugs that are sensitive for radical cure are not screened with physiologic markers such which affect proper management of the disease. The objective of the study is to relate various sources or organ specific templates: gastrin, histamine and prostaglandin relating with the disease in evaluating the potencies of cimetidine, ranitidine and omeprazole for best choice of the drugs in gastric ulcer disease treatment.Material and Methods: Plasma, gastric and antral prostaglandins, histamine and gastrin levels were studied in ninety-six (96), male and female Swiss albino rats for 28 days, using high performance liquid chromatography.Results: Male and female rats with gastric ulcer treated with cimetidine, omepraszole and ranitidine showed no significant difference (P>0.5) in gastrin and the drug groups in plasma, gastric and antral concentrations. But, there was significant difference (P<0.05) in histamine levels between cimetidine, omeprazole and ranitidine in their gastric and plasma concentration. There was no significant difference (P>0.05) in prostaglandin values between cimetidine, omeprazole and ranitidine. Also there was no significant difference (P>0.05) in gastric and plasma levels of gastrin, histamine and prostaglandin between 7, 14, 21 and 28 days treatment period. But, there was significant difference (P<0.05) in antral concentration of gastrin, histamines and prostaglandin between the drug groups. However, there was no significant difference (P>0.05) in antral gastrin between male and female rats in cimetidine and ranitidine treatment. The three drugs were associated with high levels of gastrin, histamine, low prostaglandin though cimetidine showed higher concentration of prostaglandin.Conclusion: It is concluded that gastrin, histamine and prostaglandin are sensitive indicators in evaluating anti-ulcerogenic drugs efficacies.Janaki Medical College Journal of Medical Sciences (2017) Vol. 5(2): 5-12

CO2asphyxia increases plasma norepinephrine in rats via sympathetic nerves

1998 ◽  
Vol 274 (1) ◽  
pp. R19-R22 ◽  
Author(s):  
Vicky Borovsky ◽  
Mike Herman ◽  
Gail Dunphy ◽  
Ann Caplea ◽  
Daniel Ely
Keyword(s):  
High Performance ◽  
Sympathetic Nerves ◽  
Female Rats ◽  
Plasma Norepinephrine ◽  
Specific Response ◽  
Spontaneously Hypertensive ◽  
Male And Female Rats ◽  
Y Chromosomes ◽  
Sympathetic Nerve Ending ◽  
Wistar Kyoto

The objective of this study was to determine whether the plasma norepinephrine (NE) increase in rats exposed to CO2asphyxia was due to adrenal gland release or sympathetic nerve ending (SNS) release. Plasma NE was measured by high-performance liquid chromatography in hypertensive and normotensive rats using the following protocol: control session, CO2exposure, N2exposure, reserpine + CO2, and adrenalectomy + CO2. Four strains of male and female rats were used: spontaneously hypertensive rats, Wistar-Kyoto rats, and two congenic strains with different Y chromosomes. The same rats were used throughout the experiment ( n = 80). Blood pressure measured by aortic telemetry increased ∼50–60 mmHg in response to CO2in all strains. CO2increased NE 6–10× in all strains and both genders. N2produced a significant increase in NE (73% of CO2response). Reserpine significantly decreased (67%) plasma NE after CO2. Adrenalectomy did not significantly reduce the NE response to CO2. In conclusion, the increase in plasma NE after CO2was associated with SNS release and not adrenal medullary release, was mainly due to hypoxia, and was not a specific response to CO2.

scholarly journals NMR of glycogen in exercise

1999 ◽  
Vol 58 (4) ◽  
pp. 851-859 ◽  
Author(s):  
Thomas B. Price ◽  
Douglas L. Rothman ◽  
Robert G. Shulman
Keyword(s):  
Time Resolution ◽  
Muscle Glycogen ◽  
Time Course ◽  
Glycogen Synthesis ◽  
Liver Glycogen ◽  
Invasive Technique ◽  
Human Populations ◽  
Glycogen Depletion ◽  
Non Invasive ◽  
C Nmr

Natural-abundance 13CNMR spectroscopy is a non-invasive technique that enables in vivo assessments of muscle and/or liver glycogen concentrations. Over the last several years, 13C NMR has been developed and used to obtain information about human glycogen metabolism with diet and exercise. Since NMR is non-invasive, more data points are available over a specified time course, dramatically improving the time resolution. This improved time resolution has enabled the documentation of subtleties of muscle glycogen re-synthesis following severe glycogen depletion that were not previously observed. Muscle and liver glycogen concentrations have been tracked in several different human populations under conditions that include: (1) muscle glycogen recovery from intense localized exercise with normal insulin and with insulin suppressed; (2) muscle glycogen recovery in an insulin-resistant population; (3) muscle glycogen depletion during prolonged low-intensity exercise; (4) effect of a mixed meal on postprandial muscle and liver glycogen synthesis. The present review focuses on basic 13C NMR and gives results from selected studies.

scholarly journals HSP70 Constitutive Expression in Rat Central Nervous System from Postnatal Development to Maturity

2002 ◽  
Vol 50 (9) ◽  
pp. 1161-1168 ◽  
Author(s):  
Guillermo Bodega ◽  
Celia Hernández ◽  
Isabel Suárez ◽  
Montserrat Martín ◽  
Benjamín Fernández
Keyword(s):  
Spinal Cord ◽  
Central Nervous System ◽  
Nervous System ◽  
Postnatal Development ◽  
Time Course ◽  
Constitutive Expression ◽  
Female Rats ◽  
Synaptic Membranes ◽  
Hsp70 Expression ◽  
Male And Female Rats

We studied the level of the basal (constitutive) HSP70 expression (inducible and constitutive forms) in the central nervous system (CNS) of male and female rats from the postnatal period to maturity. HSP70 levels were analyzed by immunoblotting in five different areas (cortex, hippocampus, hypothalamus, cerebellum, and spinal cord). The highest levels of HSP70 were found in juvenile rats and decreased progressively until reaching baseline levels between 2 and 4 months. A slight and nonsignificant increase in aged (2-year-old) rats compared with adult subjects was observed in some cerebral areas (cerebral cortex, hippocampus, and cerebellum). In the first weeks of postnatal development, HSP70 immunoreactivity was distributed throughout CNS sections and no specific immunopositive cells could be clearly determined. In adult animals, strong immunostaining was observed in some large neurons (Purkinje neurons and mesencephalic and spinal cord motor neurons), some perivascular and subpial astrocytes, and ependymocytes. Immunoelectron microscopy revealed that HSP70 in these cells is located in the perinuclear area and in mitochondria, rough endoplasmic reticulum, and microtubules. In neurons, strong immunolabeling was also observed in synaptic membranes. The postnatal time course of HSP70 levels and the location and size of HSP70-immunopositive cells suggest that HSP70 constitutively expressed in the rat CNS may be mainly determined by the degree of development and metabolic activity of the neural cells.

scholarly journals Measuring Faecal Glucocorticoid Metabolites to Assess Adrenocortical Activity in Reindeer

Animals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 987
Author(s):  
Şeyda Özkan Gülzari ◽  
Grete Helen Meisfjord Jørgensen ◽  
Svein Morten Eilertsen ◽  
Inger Hansen ◽  
Snorre Bekkevold Hagen ◽  
...  
Keyword(s):  
Stress Responses ◽  
Dna Analysis ◽  
Stress Hormones ◽  
Invasive Technique ◽  
Animal Conservation ◽  
Adrenocortical Activity ◽  
Non Invasive ◽  
Faecal Glucocorticoid Metabolites ◽  
Faecal Samples ◽  
Species Specific

Several non-invasive methods for assessing stress responses have been developed and validated for many animal species. Due to species-specific differences in metabolism and excretion of stress hormones, methods should be validated for each species. The aim of this study was to conduct a physiological validation of an 11-oxoaetiocholanolone enzyme immunoassay (EIA) for measuring faecal cortisol metabolites (FCMs) in male reindeer by administration of adrenocorticotrophic hormone (ACTH; intramuscular, 0.25 mg per animal). A total of 317 samples were collected from eight male reindeer over a 44 h period at Tverrvatnet in Norway in mid-winter. In addition, 114 samples were collected from a group of reindeer during normal handling and calf marking at Stjernevatn in Norway. Following ACTH injection, FCM levels (median and range) were 568 (268–2415) ng/g after two hours, 2718 (414–8550) ng/g after seven hours and 918 (500–6931) ng/g after 24 h. Levels were significantly higher from seven hours onwards compared to earlier hours (p < 0.001). The FCM levels at Stjernevatn were significantly (p < 0.001) different before (samples collected zero to two hours; median: 479 ng/g) and after calf marking (eight to ten hours; median: 1469 ng/g). Identification of the faecal samples belonging to individual animals was conducted using DNA analysis across time. This study reports a successful validation of a non-invasive technique for measuring stress in reindeer, which can be applied in future studies in the fields of biology, ethology, ecology, animal conservation and welfare.

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