Immobilization stress in rats: Effect on rectal temperature and possible role of brain monoamines in hypothermia

1981 ◽  
Vol 73 (2) ◽  
pp. 157-160 ◽  
Author(s):  
Alka Amar ◽  
A. K. Sanyal
Keyword(s):  
Rectal Temperature ◽  
Immobilization Stress ◽  
Brain Monoamines

Peripheral corticotropin-releasing factor mediates the elevation of plasma IL-6 by immobilization stress in rats

1998 ◽  
Vol 275 (5) ◽  
pp. R1461-R1467 ◽  
Author(s):  
Tetsuya Ando ◽  
Jean Rivier ◽  
Hitoshi Yanaihara ◽  
Akira Arimura
Keyword(s):  
Intravenous Injection ◽  
Intraperitoneal Injection ◽  
Immobilization Stress ◽  
Systemic Administration ◽  
Corticotropin Releasing Factor ◽  
Elevated Plasma ◽  
Adrenalectomized Rats

We previously reported the elevation of plasma interleukin (IL)-6 activity in response to immobilization stress in rats. To investigate the role of peripheral corticotropin-releasing factor (CRF) in this response, we examined the effects of CRF antagonists on immobilization-induced IL-6 response. Intravenous pretreatment with either [d-Phe12,Nle21,38,CαMeLeu37]-anti-human rat (h/r) CRF12—41(1.5 mg/kg) or cyclo(30—33)[d-Phe12, Nle21,38,Glu30,Lys33]-h/rCRF12—41(Astressin, 0.5 mg/kg) attenuated the IL-6 response to immobilization, which confirmed our previous finding that systemic administration of an antiserum against CRF blocked this response. In addition, an intraperitoneal injection of h/rCRF (100 μg/kg) or rat urocortin (10 and 100 μg/kg) increased the plasma IL-6 activity, mimicking the response to immobilization. An intravenous injection of h/rCRF (100 μg/kg) also elevated plasma IL-6 in adrenalectomized rats. These findings suggest that peripheral CRF mediates the plasma IL-6 elevation in response to immobilization.

scholarly journals Cardioprotective Properties of Opioid Receptor Agonists in Rats With Stress-Induced Cardiac Injury

2019 ◽  
pp. 375-384
Author(s):  
E. PROKUDINA ◽  
L MASLOV ◽  
N. NARYZHNAYA ◽  
S. TSIBULNIKOV ◽  
Y. LISHMANOV ◽  
...  
Keyword(s):  
Opioid Receptor ◽  
Wistar Rats ◽  
Immobilization Stress ◽  
Cardiac Injury ◽  
Endogenous Opioids ◽  
Heart Injury ◽  
Mr 2266 ◽  
Opioid Receptor Agonists ◽  
Stimulation Of

The objectives of this study were to investigate the role of endogenous opioids in the mediation of stress-induced cardiomyopathy (SIC), and to evaluate which opioid receptors regulate heart resistance to immobilization stress. Wistar rats were subjected to 24 h immobilization stress. Stress-induced heart injury was assessed by 99mTc-pyrophosphate accumulation in the heart. The opioid receptor (OR) antagonists (naltrexone, NxMB – naltrexone methyl bromide, MR 2266, ICI 174.864) and agonists (DALDA, DAMGO, DSLET, U-50,488) were administered intraperitoneally prior to immobilization and 12 h after the start of stress. In addition, the selective µ OR agonists PL017 and DAMGO were administered intracerebroventricularly prior to stress. Finally pretreatment with guanethidine was used. Naltrexone did not alter the cardiac 99mTc-PP accumulation in stressed rats. NxMB aggravated stress-induced cardiomyopathy (P=0.005) (SIC). The selective µ OR agonist DALDA, which does not cross the blood-brain barrier, completely prevented (P=0.006) SIC. The µ OR agonist DAMGO exhibited weaker effect than DALDA. The selective δ ligand (DSLET) and κ OR ligand (U-50,488) did not alter stress-induced 99mTc-pyrophosphate accumulation in the heart. Intracerebroventricular administration of the µ OR agonists aggravated SIC. Pretreatment with guanethidine abolished this effect (P=0.01). Guanethidine alone exhibited cardioprotective properties. A stimulation of central µ OR promotes an appearance of SIC. In contrast, stimulation of peripheral µ OR contributes to an increase in cardiac tolerance to stress.

Oral Administration of Rauwolfia Serpentina Plant Extract Mitigated Immobilization Stress-Induced Biochemical and Behavioral Deficits in Rats

2020 ◽  
Vol 42 (6) ◽  
pp. 875-875
Author(s):  
Erum Shireen Erum Shireen ◽  
Wafa Binte Ali Wafa Binte Ali ◽  
Maria Masroor Maria Masroor ◽  
Shamim A Qureshi Shamim A Qureshi ◽  
Sehrish Kiran Sehrish Kiran ◽  
...  
Keyword(s):  
Antioxidant Enzymes ◽  
Oral Administration ◽  
Plant Extract ◽  
Psychotic Disorders ◽  
Immobilization Stress ◽  
Neuroprotective Effects ◽  
Behavioral Deficits ◽  
Glucose Levels ◽  
Rauwolfia Serpentina

Rauwolfia Serpentina is a medicinal herb used for hypertension and psychotic disorders. In this study neuroprotective effects of Rauwolfia serpentina plant extract following the exposure to acute immobilization (2h) stress in rats were investigated. The extract of the plant administered orally at non-sedative dose 30mg/kg before immobilization (2h) to observe stress induced behavioral deficits. Neuroprotective efficacy of extract was assessed in terms of alteration in activities of antioxidant enzymes like superoxide dismutase (SOD) and catalase (CAT). We also monitored leptin, corticosterone and glucose levels in plasma to obtain an imminent role of Rauwolfia serpentina. Animals were orally administered with Rauwolfia serpentina (30mg/kg) while controls receive saline (1ml/kg). Each group was subdivided into stressed and unstressed groups. Behavioral deficits were monitored in the open field and light dark activity box. Animals were decapitated; plasma samples were collected for CAT, SOD, corticosterone, leptin and glucose estimation. Orally administered Rauwolfia serpentina attenuates stress induced behavioral deficits and rise antioxidant enzymes levels. Plant extract also prevents the stress-induced increase in corticosterone but glucose levels do not manifest any significant change. Immobilization stress (2h) induced decrease of plasma leptin levels were reversed by Rauwolfia serpentina. Therefore, the present study suggests that Rauwolfia serpentina has potentiality to antagonize undesirable effects of immobilization stress (2h) by reducing stress perception and inhibitory effects of stress on the activity of hypothalamic pituitary adrenal (HPA) axis and animal behaviors. Despite an apparent role of Rauwolfia serpentina the mechanism of action at molecular level causing the acute anxiolytic effects of oral administration of plant extract remains to be determined.

Effect of cerebrospinal fluid hyperosmolality on sweating in the heat-stressed patas monkey

1989 ◽  
Vol 67 (1) ◽  
pp. 128-133 ◽  
Author(s):  
M. D. Owen ◽  
R. D. Matthes ◽  
C. V. Gisolfi
Keyword(s):  
Cerebrospinal Fluid ◽  
Rectal Temperature ◽  
Sweat Rate ◽  
Recovery Period ◽  
Erythrocebus Patas ◽  
Artificial Cerebrospinal Fluid ◽  
Skin Temperatures ◽  
Central Stimulation ◽  
Osmotic Stimuli

Dehydration increases the osmolality of body fluids and decreases the rate of sweating during thermal stress. By localizing osmotic stimuli to central nervous system tissues, this study assessed the role of central stimulation on sweating in a heat-stressed nonhuman primate. Lenperone-tranquilized patas monkeys (Erythrocebus patas n = 5), exposed to 41 +/- 2 degrees C, were monitored for calf sweat rate, rectal and mean skin temperatures, oxygen consumption, and heart rate during infusions (255–413 microliters) of hypertonic artificial cerebrospinal fluid (ACSF) into the third cerebral ventricle. ACSF made hypertonic with NaCl to yield osmolalities of 800 and 1,000 mosmol/kgH2O significantly decreased sweat rate compared with control ACSF (285 mosmol/kgH2O), achieving maximal reductions during infusion of 37 and 53%, respectively. Rectal temperature significantly increased during the recovery period, reaching elevations of 0.69 and 0.72 degrees C, respectively, at 20 min postinfusion. In contrast, ACSF made hypertonic with sucrose (800 mosmol/kgH2O) failed to change sweat rate or rectal temperature during infusion in three animals. Thus, intracerebroventricular infusions of hypertonic ACSF mimicked dehydration-induced effects on thermoregulation. The reduction in heat loss during infusion appeared to depend on an elevation in cerebrospinal fluid [Na+] and not osmolality per se.

Role of thermal and exercise factors in the mechanism of hypervolemia

1980 ◽  
Vol 48 (4) ◽  
pp. 657-664 ◽  
Author(s):  
V. A. Convertino ◽  
J. E. Greenleaf ◽  
E. M. Bernauer
Keyword(s):  
Exercise Training ◽  
Plasma Protein ◽  
Plasma Volume ◽  
Rectal Temperature ◽  
Heat Exposure ◽  
Bicycle Ergometer ◽  
Thermal Factor ◽  
Albumin Content ◽  
Exercise Induced

Our purpose was to determine whether the chronic increase in plasma volume (PV), resulting from heat exposure (HE) and exercise training (ET), was due only to elevated rectal temperature (Tre) or whether there were additional nonthermal factors related to the exercise. Eight men were divided into two groups. The HE group sat for 2 h/day (Tdb = 42 degrees C, 93% rh) for 8 consecutive days; Tre was raised by 1.72 +/- 0.04 degrees C to 38.5 degrees C each day. The ET group rode a bicycle ergometer for 2 h/day for 8 days (Tdb = 25 degrees C, 60% rh) at a load (60-65 Vo2max) that gave the same area under their Tre curve. PV increased by 177 ml (4.9%, P less than 0.05) in the HE group and by 427 ml (12.0%, P less than 0.05) in the ET group. This exercise-induced hypervolemia was associated with thermal factor(s) that contributed 40% and nonthermal factors that accounted for the remaining 60%. Some nonthermal, exercise-induced factors were twofold greater increases in plasma osmotic and vasopressin levels during exercise, and a fivefold increase in resting plasma protein (albumin) content.

Role of conjugation and red blood cells for inactivation of circulating normetanephrine

1984 ◽  
Vol 247 (1) ◽  
pp. R208-R211
Author(s):  
S. Yoneda ◽  
N. Alexander ◽  
N. D. Vlachakis ◽  
R. F. Maronde
Keyword(s):  
Immobilization Stress ◽  
Glucuronic Acid ◽  
Simultaneous Increase ◽  
Sympathoadrenal System ◽  
Methyltransferase Activity ◽  
Substrate Saturation ◽  
The Mean ◽  
Catechol Methyltransferase ◽  
Mean Concentration

Plasma and red blood cell (RBC) concentrations of normetanephrine (NMN), in both free and glucuronide-conjugated forms, were measured before, during, and after forced immobilization, an intense stressor of the sympathoadrenal system of rats. In this study NMN glucuronide was deconjugated by enzymatic hydrolysis; free and total NMN were assayed by radioenzymatic, thin-layer chromatographic procedures. In plasma, free NMN and NMN glucuronide are 777 +/- 99 and 792 +/- 74 pg/ml, respectively, when rats are at rest. Both free NMN and NMN glucuronide increased about 200% after 15 min of stress; in absolute amounts, increases were equivalent to that of the simultaneous increase in norepinephrine (NE). At 2 h of stress, NMN glucuronide, but not free NMN, increased further and significantly. The mean concentration of RBC-free NMN is about 50 times higher than that of plasma-free NMN, and it did not change significantly during stress; RBCs do not contain conjugated NMN. RBC NMN levels showed a strong correlation with RBC catechol methyltransferase activity. The latter seems to operate under conditions of substrate saturation; an acute release of NE leads to temporary storage of NE in RBCs but not conversion to NMN. The results indicate that conjugation of NMN with glucuronic acid is an important route for inactivation of plasma NMN formed during forced immobilization stress, whereas free NMN does not accumulate in RBCs during stress.

Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude IV. Role of the fleece in thermoregulation in German Merino ewes

1960 ◽  
Vol 55 (3) ◽  
pp. 311-315
Author(s):  
R. B. Symington
Keyword(s):  
Thermal Stress ◽  
Body Temperature ◽  
Respiratory Rate ◽  
Skin Temperature ◽  
Rectal Temperature ◽  
High Heat ◽  
Diurnal Fluctuation ◽  
Body Temperature Regulation ◽  
Southern Rhodesia

The influence of fleece on thermoregulation in German Merino ewes was investigated in Rhodesia. Comparative heat tolerances of Persian Blackhead, indigenous Native and shorn and unshorn Merino ewes were obtained during the hottest month of the year in Northern Rhodesia. The main thermolytic responses in unshorn, partially shorn and completely shorn Merino ewes were measured at 7.0 a.m.; 10.0 a.m.; 1.0 p.m. and 4.0 p.m. during April in Southern Rhodesia.1. Unshorn Merino ewes showed more and shorn Merino ewes less effective body temperature regulation than Persian or Native ewes. High heat tolerance in unshorn Merinos was due primarily to insulation by the fleece and not to more efficient physiological thermolysis than in hair breeds. No ewe showed signs of undue thermal stress and feed intake was not affected by heat.2. Increases in rectal temperature and respiratory rate between 7.0 a.m. and 1.0 p.m. of Merinos in Southern Rhodesia were related inversely to fleece length. Body temperature did not differ significantly at 1.0 p.m. owing to differential rates of increase in respiratory rate.3. Magnitude of the diurnal fluctuation in skin temperature was also related inversely to fleece length. Partially shorn ewes, however, began with and maintained highest skin temperature through the heat of the day. In all groups skin temperature fell after 10.0 a.m. although ambient temperature continued to rise. This fall could not be attributed to sweating since moisture secretion declined simultaneously.

Effect of brain monoamines on the secretion of adrenocorticotrophic hormone

1982 ◽  
Vol 101 (2) ◽  
pp. 180-186 ◽  
Author(s):  
Alka Amar ◽  
S. Mandal ◽  
A. K. Sanyal
Keyword(s):  
Dopaminergic Neurons ◽  
Adrenal Glands ◽  
Plasma Corticosterone ◽  
Albino Rats ◽  
Adrenocorticotrophic Hormone ◽  
Brain Monoamines ◽  
Acth Secretion ◽  
Acute Increase

Abstract. The role of brain monoamines (5-HT, NA and DA) in the secretion of adrenocorticotrophic hormone (ACTH) was studied in view of contradictory reports. Plasma corticosterone levels and the rate of synthesis of corticosterone in vitro by the adrenal gland were estimated in albino rats and have been taken as the index of ACTH activity. These estimations were done in unstressed and stressed, and in untreated and treated rats. Drugs were administered intracerebroventricularly to the rats to cause selective degeneration of tryptaminergic, noradrenergic or dopaminergic neurons. The results show that plasma corticosterone levels and the rate of synthesis of corticosterone were significantly decreased after selective degeneration of tryptaminergic neurons in unstressed rats. After selective degeneration of either tryptaminergic or noradrenergic neurons, the acute increase in the plasma corticosterone levels and rate of synthesis of corticosterone in vitro by adrenal glands in stressed rats were significantly inhibited. These results have been interpreted to suggest that the central tonic control on adrenal glands may be 5-HT mediated and that during stress ACTH secretion may be both 5-HT and NA mediated. DA does not seem to have significant role in the regulation of ACTH secretion.

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