Some biochemical and hormonal aspects of experimental ovine pregnancy toxaemia

1966 ◽  
Vol 67 (1) ◽  
pp. 129-138 ◽  
Author(s):  
N. Saba ◽  
K. N. Burns ◽  
N. F. Cunningham ◽  
C. Nancy Hebert ◽  
D. S. P. Patterson

1. Some of the effects of stress, fasting and ACTH injections in pregnant ewes were investigated.2. A 6-day fast produced a relatively mild hypoglycaemia and hyperketonaemia without inducing pregnancy toxaemia.3. Stress of transport produced an immediate slight rise in plasma cortisol; 4 hr. later the plasma cortisol had returned to the pre-stress levels.4. A combination of stress and fasting produced severe hypoglycaemia, hyperketonaemia and subacute pregnancy toxaemia, but there was no increase in plasma cortisol levels.5. Daily injections of ACTH resulted in a fourfold increase in plasma cortisol and prevented the development of hypoglycaemia, severe hyperketonaemia, and pregnancy toxaemia in pregnant ewes subjected to stress and fasting.6. Changes in plasma concentrations of NEFA, urea, proteins, catecholamines and insulin were also investigated.

2009 ◽  
Vol 161 (1) ◽  
pp. 119-130 ◽  
Author(s):  
Gudmundur Johannsson ◽  
Ragnhildur Bergthorsdottir ◽  
Anna G Nilsson ◽  
Hans Lennernas ◽  
Thomas Hedner ◽  
...  

BackgroundEndogenous plasma cortisol levels have a well-defined circadian rhythm. The aim of this project is to develop a once daily oral dual-release formulation for cortisol replacement therapy that mimics the diurnal variation in the plasma cortisol profile.ObjectiveTo determine single-dose plasma pharmacokinetics and dose-proportionality of oral 5 and 20 mg dual-release hydrocortisone tablets in healthy volunteers. In addition, the effect of food intake was investigated for the 20 mg dose.DesignA randomised, controlled, two-way cross-over, double-blind, phase I study of oral hydrocortisone (modified (dual) release; 5 and 20 mg) with an open food-interaction arm.MethodsThe single dose pharmacokinetic studies were performed with betamethasone suppression. The two first study days were blinded and randomised between morning administration of 5 and 20 mg tablet in a fasting state. The third day was open with a 20 mg tablet taken 30 min after a high-calorie, high-fat meal. The plasma samples were assayed using both a validated LC–MS/MS and an immunoassay. The plasma pharmacokinetic variables were calculated using non-compartmental data analysis.ResultsThe time to reach a clinically significant plasma concentration of cortisol (>200 nmol/l) was within 20 min and a mean peak of 431 (s.d. 126) nmol/l was obtained within 50 min after administration of the 20 mg tablet. Plasma cortisol levels remained above 200 nmol/l for around 6 h thereafter and all plasma concentrations 18–24 h after intake were below 50 nmol/l. In the fed state the time to reach 200 nmol/l was delayed by 28 and 9 min based on LC–MS/MS and immunoassay, respectively. The 5 and 20 mg tablets produced an increase in plasma exposure of cortisol that was not fully dose proportional.ConclusionThe dual release hydrocortisone tablet with once-daily administration produced a diurnal plasma cortisol profile mimicking the physiological serum cortisol profile.


1996 ◽  
Vol 199 (5) ◽  
pp. 1043-1051 ◽  
Author(s):  
S Kakizawa ◽  
T Kaneko ◽  
T Hirano

Somatolactin (SL) is a putative pituitary hormone of the growth hormone (GH)/prolactin (PRL) family in fish; its physiological function has yet to be determined. Acidosis was induced in rainbow trout (Oncorhynchus mykiss) by exposure to acidic water (pH 4.5) or by exhaustive exercise, and plasma concentrations of SL, PRL and GH as well as other plasma parameters were examined. A decrease in blood pH was observed in fish from 1 day after water acidification until the end of the experiment at day 7. Plasma SL levels in the acid-exposed fish increased, reached a peak on day 1 and then returned to the initial level by day 4. No change was seen in plasma concentrations of PRL throughout the experiment. Plasma levels of GH, in contrast, decreased in the acid-exposed fish on days 2 and 4. Plasma cortisol levels in the acid-exposed fish were higher than the control level on days 4 and 7, although plasma cortisol levels did not increase above the initial level in response to water acidification. There was no significant change in the expression of SL-, PRL- and GH-mRNA in the pituitary gland. Levels of plasma Na+ and lactate were reduced 12 h after water acidification and remained low throughout the experiment. Exhaustive exercise in shallow water at neutral pH (7.5) resulted in a transient but pronounced acidosis, associated with increases in plasma SL, cortisol, Ca2+, phosphate and lactate levels. Plasma SL levels returned to the initial level along with the recovery of blood acid-base status. In contrast, plasma cortisol levels stayed elevated even 24 h after exercise. There was no correlation between plasma PRL and GH levels and blood pH. Elevation of plasma SL levels during acidosis suggests the possible involvement of SL in acid-base regulation in rainbow trout.


1998 ◽  
Vol 157 (3) ◽  
pp. 425-432 ◽  
Author(s):  
SL Alexander ◽  
CH Irvine

Plasma cortisol is largely bound to corticosteroid-binding globulin (CBG), which regulates its bioavailability by restricting exit from capillaries. Levels of CBG may be altered by several factors including stress and this can influence the amount of cortisol reaching cells. This study investigated the effect of social instability on plasma concentrations of CBG, total and free (not protein bound) cortisol in horses. Horses new to our research herd ('newcomers') were confined in a small yard with four dominant resident horses for 3-4 h daily for 3-4 (n = 5) or 9-14 (n = 3) days. Jugular blood was collected in the mornings from newcomers before the period of stress began ('pre-stress'), and then before each day's stress. Residents were bled before stress on the first and thirteenth day. Residents always behaved aggressively towards newcomers. By the end of the stress period, all newcomers were subordinate to residents. In newcomers (n = 8) after 3-4 days of social stress, CBG binding capacity had fallen (P = 0.0025), while free cortisol concentrations had risen (P = 0.0016) from pre-stress values. In contrast, total cortisol did not change. In residents, CBG had decreased slightly but significantly (P = 0.0162) after 12 days of stress. Residents and newcomers did not differ in pre-stress CBG binding capacity, total or free cortisol concentrations. However, by the second week of stress, CBG binding capacity was lower (P = 0.015) and free cortisol higher (P = 0.030) in newcomers (n = 3) than in residents. Total cortisol did not differ between the groups. In conclusion social stress clearly affected the adrenal axis of subordinate newcomer horses, lowering the binding capacity of CBG and raising free cortisol concentrations. However, no effect of stress could be detected when only total cortisol was measured. Therefore, to assess adrenal axis status accurately in horses, it is essential to monitor the binding capacity of CBG and free cortisol concentrations in addition to total cortisol levels.


Animals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1578
Author(s):  
Giancarlo Bozzo ◽  
Barbara Padalino ◽  
Elisabetta Bonerba ◽  
Roberta Barrasso ◽  
Vincenzo Tufarelli ◽  
...  

The aim of this pilot study was to evaluate the relationship between journey duration, deck level and activation patterns of the hypothalamic-pituitary-adrenocortical axis (HPA) and sympathetic adrenal medullary system (SAM) in pigs. A total of 90 pigs were examined. The animals came from three different Italian farms associated with the same slaughterhouse located in Bari (Apulia region-Italy). A group of thirty animals was transported from Pordenone (11 h journey); a second group was transported from Terni (6.5 h journey); a third group was transported from Benevento (3 h journey). The animals were transported in the same vehicle, which complied with the structural characteristics indicated in the Council Regulation (EC) No. 1/2005. The truck was composed of a lorry and a trailer, each one divided into three decks. Only the animals transported in the trailer were tested for the study. Before transportation, blood samples were collected on each farm, at 6:00 a.m., from 30 pigs randomly selected out of 135 pigs ready to be transported. Blood samples were also collected during slaughter to evaluate plasma cortisol, epinephrine and norepinephrine, around 6:00 a.m. A journey duration of 11 h was associated with significantly higher plasma concentrations of stress hormones compared with shorter journeys. This increase was proportional to the journey duration, with the pigs travelling for 6.5 h displaying intermediate concentrations between those noticed after 3 h and 11 h journeys. The interaction between deck and journey distance was not significant on epinephrine, norepinephrine or cortisol levels collected at arrival. There was a significant effect of deck level on norepinephrine levels (p < 0.0001), a tendency to influence epinephrine levels (p = 0.073) but no effect on cortisol levels (p = 0.945). Overall, we observed that an 11 h-long journey seemed to impact negatively on pigs’ HPA-SAM activity, likely requiring the animals to spend more time in the lairage facilities to recover.


1989 ◽  
Vol 120 (1) ◽  
pp. 50-54 ◽  
Author(s):  
S. N. Thornton ◽  
R. F. Parrott

Abstract. Ovariectomized ewes (N = 7) were dehydrated for 24 h and then given iv injections of saline vehicle or 8 or 64 mg naloxone hydrochloride in saline. Blood samples were taken by jugular venepuncture before and after dehydration and at intervals during the 90 min period directly following naloxone treatment. Plasma concentrations of AVP, OT and cortisol were measured by radioimmunoassay. Plasma AVP levels and osmolality increased with dehydration, OT concentrations showed no consistent change, and cortisol levels were unaffected. After administration of naloxone, AVP and OT concentrations did not alter. The sampling procedure increased plasma cortisol levels and the duration of this response was prolonged by the 64 mg dose of naloxone.


1989 ◽  
Vol 49 (1) ◽  
pp. 103-107 ◽  
Author(s):  
D. P. Fordham ◽  
G. A. Lincoln ◽  
E. Ssewannyana ◽  
R. G. Rodway

ABSTRACTThe effects of the routine stressful stimuli of handling, transport and slaughter on the plasma concentrations of cortisol and β-endorphin have been studied in lambs. Blood samples were obtained from group 1 lambs after rounding up, after transport and at slaughter. Group 2 lambs were treated similarly except that blood was collected only at slaughter. Group 3 lambs served as controls and were blood sampled twice daily for 5 days to accustom them to handling before being slaughtered. Plasma cortisol and β-endorphin concentrations were increased above control levels by rounding up and transport, and were further increased at slaughter. Group 3 lambs, however, had very much lower β-endorphin levels at slaughter than the other two groups, although their cortisol levels were similar, β-endorphin concentrations declined during the 5-day blood sampling period in group 3 animals but cortisol levels were unchanged. The results suggest that although levels of both hormones are increased by stress, they are not necessarily released concomitantly.


1960 ◽  
Vol 11 (3) ◽  
pp. 364 ◽  
Author(s):  
RL Reid

Plasma cortisol levels in fed and fasted non-pregnant and in undernourished pregnant ewes were consistently less than 1.5 µg per 100 ml. Most values were considerably above this level in 20 field cases of pregnancy toxaemia, 31 of 52 values being greater than 3 µg per 100 ml. These levels must be regarded as abnormally high in sheep. Pregnancy toxaemia was induced in two experiments by fasting after a period of severe under nutrition and in two by fasting previously well-nourished ewes in the presence of severe psychological stresses. The onset of clinical signs was associated with marked increases above normal in plasma cortisol. In three experiments involving a total of 23 previously well-nourished ewes, 11 of which carried twins or triplets, only one mild case of pregnancy toxaemia was induced by complete fasting in late pregnancy for up to 6 days, in the absence of any additional environmental stress. Pregnancy toxaemia was readily induced in 24 of 38 ewes in three experiments when severe psychological stresses accompanied fasting in late pregnancy. Adrenal hypertrophy, indicating sustained adrenal hyperactivity, was most pronounced in field cases of pregnancy toxaemia induced primarily by sustained under nutrition. Fresh adrenal weights (total of two adrenals) averaged 6.7 g compared to 3.8 g in normal non-pregnant ewes. Mean plasma cortisol levels in ewes with pregnancy toxaemia were significantly correlated with fresh adrenal weight. The suggestions that abnormalities of carbohydrate and fat metabolism in ewes with pregnancy toxaemia are those of adrenal steroid diabetes, and that cerebral depression may be largely a consequence of a cortisol-induced inhibition of glucose utilization, are discussed in the light of the probable metabolic effects of cortisol in the undernourished pregnant ewe.


1965 ◽  
Vol 64 (1) ◽  
pp. 11-14 ◽  
Author(s):  
N. Saba

Pregnancy toxaemia in ewes is a metabolic disorder which may occur during the last month of pregnancy. Typical symptoms are anorexia, hypoglycaemia, hyperketonaemia, blindness, ataxia and recumbency. The condition usually proves fatal. Reid & Hogan (1959) have put forward the suggestion that pregnancy toxaemia is an adrenal steroid diabetes. However, pregnancy toxaemia in ewes is generally associated with starvation or severe undernutrition, and McClymont & Setchell (1955) have suggested that under these conditions the symptoms of pregnancy toxaemia are due to cerebral depression caused by hypoglycaemia. As part of investigations on pregnancy toxaemia, adrenal steroid metabolism in ewes was studied. This paper presents data on plasma cortisol levels during the last month of pregnancy in ewes, and the possible effects of undernutrition and cold on these levels.


Sign in / Sign up

Export Citation Format

Share Document