CHANGES IN THE CONCENTRATION OF LUTEINIZING HORMONE IN PLASMA DURING DEVELOPMENT IN THE GUINEA-PIG

1975 ◽  
Vol 64 (3) ◽  
pp. 511-520 ◽  
Author(s):  
B. T. DONOVAN ◽  
M. B. TER HAAR ◽  
A. N. LOCKHART ◽  
P. C. B. MACKINNON ◽  
J. M. MATTOCK ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Luteinizing Hormone ◽  
Guinea Pig ◽  
Guinea Pigs ◽  
Plasma Concentrations ◽  
Maternal Plasma ◽  
Significant Rise ◽  
Cross Reaction ◽  
Blood Collection ◽  
Postnatal Life

SUMMARY The concentration of LH in the plasma of guinea-pigs from day 50 of gestation to day 45 of postnatal life was assayed by radioimmunoassay utilizing a cross-reaction with anti-ovine LH antiserum. The effect of gonadectomy in infancy and in the adult upon the plasma concentration of LH was also studied. The LH concentration in the plasma of male or female foetuses was high immediately prenatally and fell at birth. High levels of LH were again detected in male, with a lesser increase in female, guinea-pigs over the first 10 days postnatally. Maternal plasma concentrations of LH remained consistently low. Removal of the gonads on days 0, 5, 10, 15, 25 or 35 of postnatal life, followed by blood collection at autopsy 10 days later, caused a significant rise in plasma LH content at all ages. The rise in plasma LH after gonadectomy in adults was less marked in male than in female guinea-pigs.

CHANGES IN THE CONCENTRATION OF FOLLICLE-STIMULATING HORMONE IN PLASMA DURING DEVELOPMENT IN THE GUINEA-PIG

1975 ◽  
Vol 64 (3) ◽  
pp. 521-528 ◽  
Author(s):  
B. T. DONOVAN ◽  
M. B. TER HAAR ◽  
A. N. LOCKHART ◽  
M. J. PEDDIE
Keyword(s):  
Guinea Pig ◽  
Plasma Levels ◽  
Guinea Pigs ◽  
Follicle Stimulating Hormone ◽  
Cross Reaction ◽  
Postnatal Life ◽  
Transient Rise ◽  
The Mean ◽  
Stimulating Hormone

SUMMARY The concentration of FSH in the plasma of guinea-pigs from day 50 of gestation to day 45 of postnatal life was assayed by a radioimmunological procedure utilizing a cross-reaction with the NIAMDD S6 antiserum to rat FSH. At 68 days of gestation the mean plasma FSH concentration of female foetuses was greater than that of the males, although the concentrations in the two sexes were similar on day 50 of gestation. Maternal levels remained consistently low throughout gestation. Postnatally there were no marked changes in plasma FSH levels through to maturity, although a transient rise in the male occurred over the first 3 days after birth. Gonadectomy on days 0, 5, 10, 15, 25 or 35 of postnatal life, or when adult, resulted in a significant increase in plasma levels of FSH within 10 days. The rise in plasma FSH concentration was greater in males than in females at all ages, although a larger increase was observed in females spayed at 5 or 10 days of age than at other times.

PLACENTAL TRANSFER OF INSULIN-131I IN GUINEA PIGS IMMUNIZED AGAINST INSULIN

1966 ◽  
Vol 52 (2) ◽  
pp. 276-291 ◽  
Author(s):  
Jan I. Thorell
Keyword(s):  
Plasma Concentration ◽  
Guinea Pigs ◽  
Placental Transfer ◽  
Maternal Plasma ◽  
Insulin Antibodies ◽  
Insulin Antibody

ABSTRACT The placenta is considered to be impermeable or only slightly permeable to insulin. Insulin antibodies are transferred from mother to foetus in man and in guinea pigs. The passage of insulin-131I from mother to foetus was studied in guinea pigs with and without antibodies against insulin. Antibody-bound insulin-131I was recovered in plasma from foetuses of immunized pregnant guinea pigs, at intervals of more than 5 hours after the injection of insulin-131I to the mother. The foetal levels of insulin-131I were rather low, the highest recorded value being 27% of the maternal plasma concentration. This peak was reached 32 hours after the injection. No insulin-131I was found in the foetuses of non-immunized guinea pigs.

PLASMA CONCENTRATIONS OF LUTEINIZING HORMONE, TESTOSTERONE AND ANDROSTENEDIONE IN CASTRATED AND ADRENALECTOMIZED BULL CALVES

1978 ◽  
Vol 79 (1) ◽  
pp. 137-138 ◽  
Author(s):  
J. J. BASS ◽  
A. J. PETERSON ◽  
E. PAYNE
Keyword(s):  
New Zealand ◽  
Plasma Concentration ◽  
Luteinizing Hormone ◽  
Agricultural Research ◽  
Plasma Concentrations ◽  
Young Male ◽  
Research Centre ◽  
Similar Magnitude ◽  
Research Division ◽  
Bull Calves

Ministry of Agriculture and Fisheries, Research Division, Ruakura Agricultural Research Centre, Hamilton, New Zealand (Received 17 April 1978) An increase in the plasma concentration of luteinizing hormone (LH) occurs in response to castration in bull calves aged 1–4 months; this response is of similar magnitude to that seen in cattle castrated as adults (Odell, Hescox & Kiddy, 1970). In bull calves castrated at birth, however, there is no increase in the plasma concentration of LH until after 28 days of age (Bass, Peterson, Payne & Jarnet, 1977). In other species a range of responses to castration has been reported. Gonadectomy of male guinea-pigs 0–35 days after birth produces an increase in the plasma concentration of LH similar to that observed in guineapigs castrated as adults (Donovan, ter Haar, Lockhart, MacKinnon, Mattock & Peddie, 1975). In contrast, the castration of young male macaques does not cause an immediate increase in the

scholarly journals Dietary calcium and phosphate restriction in guinea-pigs during pregnancy: fetal mineralization induces maternal hypocalcaemia despite increased 1α,25-dihydroxycholecalciferol concentrations

2000 ◽  
Vol 84 (4) ◽  
pp. 495-504 ◽  
Author(s):  
Katrien Rummens ◽  
Erik Van Herck ◽  
Rita van Bree ◽  
Roger Bouillon ◽  
F. André Van Assche ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Guinea Pigs ◽  
Plasma Concentrations ◽  
Dual Energy ◽  
Whole Body ◽  
Hydroxylase Activity ◽  
Mineral Density ◽  
X Ray ◽  
Highly Correlated ◽  
Stimulation Of

Guinea-pig fetuses at term are mineralized to a degree comparable with human fetuses, which makes the guinea-pig an attractive animal model to study maternal–fetal interactions with regard to Ca and phosphate (P) homeostasis. We studied non-pregnant and pregnant (day 57) vitamin D-replete guinea-pigs, fed either a normal guinea-pig chow with 9·6 g Ca/kg and 4·9 g P/kg or a study diet with 2 g Ca/kg and 1 g P/kg (low-Ca–P diet) for 7–8 weeks. Both pregnancy and the low-Ca–P diet decreased plasma concentrations of 25-hydroxycholecalciferol (25(OH)D3), but increased total and free 1α,25-dihydroxycholecalciferol (1,25(OH)2D3), strongly suggesting an additive stimulation of 1α-hydroxylase activity. Maternal and fetal 25(OH)D3and 1,25(OH)2D3levels were highly correlated (r0·82 and 0·92 respectively, P<0·001). Dual-energy absorption X-ray absorptiometry (DXA) showed that both pregnancy and the low-Ca–P diet decreased bone mineral density (BMD) of the maternal femur, particularly at the distal metaphysis. Despite higher 1,25(OH)2D3concentrations and lower BMD, pregnant animals on the low-Ca–P diet were hypocalcaemic; blood Ca2+levels were inversely correlated with the number of fetuses in this group (r-0·93, P<0·001). Fetal growth as well as mineralization (assessed by whole-body and femoral DXA, bone histomorphometry and plasma–bone osteocalcin measurements) were unaltered in the low-Ca–P group. In conclusion, fetal mineralization proceeds normally but induces maternal hypocalcaemia in guinea-pigs with dietary restriction of Ca and P.

Concentrations of luteinizing hormone and progesterone in plasma during sexual development of the Khaki Campbell duck

1982 ◽  
Vol 93 (1) ◽  
pp. 47-53 ◽  
Author(s):  
Susan C. Wilson ◽  
T. R. Morris
Keyword(s):  
Plasma Concentration ◽  
Luteinizing Hormone ◽  
Negative Correlation ◽  
Sexual Development ◽  
Plasma Concentrations ◽  
Winter Solstice ◽  
Pronounced Increase ◽  
Threefold Increase ◽  
Lh Release

Concentrations of LH and progesterone were measured in the plasma of ducks which were, from 3 weeks of age, raised on either a constant photoperiod of 16 h light: 8 h darkness or a lighting schedule which simulated natural changes in daylength. In ducks raised on a constant photoperiod of 16 h light: 8 h darkness the plasma concentration of LH increased steeply between 7 and 3·5 weeks before the onset of lay. Concentrations of LH then declined, gradually at first, but then rapidly during the 7 days before the first oviposition in association with a pronounced increase in the plasma concentration of progesterone. During the 18 days before the first egg was laid there was a significant (P < 0·01) negative correlation between the plasma concentrations of LH and progesterone. The patterns of LH release during sexual development of ducks raised on a schedule which simulated natural changes in daylength were variable but could be categorized according to the daylength at which each duck came into lay. In ducks coming into lay soon after the winter solstice when daylength was short (8·0–8·5 h light/day) there was a pronounced 15-fold prepubertal increase in the plasma concentration of LH although in some ducks high LH levels were not maintained until 3–4 weeks before the first oviposition and were not always followed by a rise in the plasma concentration of progesterone. In contrast, in ducks coming into lay when daylength had increased to 11·0–11·5 h light/day there were only minor fluctuations in the plasma concentration of LH until a small two- to threefold increase in LH was observed during the 2 weeks before the first oviposition.

scholarly journals Efficacy of the Investigational Echinocandin ASP9726 in a Guinea Pig Model of Invasive Pulmonary Aspergillosis

2015 ◽  
Vol 59 (5) ◽  
pp. 2875-2881 ◽  
Author(s):  
Nathan P. Wiederhold ◽  
Laura K. Najvar ◽  
Satoru Matsumoto ◽  
Rosie A. Bocanegra ◽  
Monica L. Herrera ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Quantitative Pcr ◽  
Guinea Pigs ◽  
Plasma Concentrations ◽  
Invasive Pulmonary Aspergillosis ◽  
Pig Model ◽  
Pulmonary Aspergillosis ◽  
Content Type ◽  
Fungal Burden ◽  
Guinea Pig Model

ABSTRACTASP9726 is an investigational echinocandin within vitroactivity againstAspergillusspecies. We evaluated the pharmacokinetics and efficacy of this agent in an established guinea pig model of invasive pulmonary aspergillosis. ASP9726 plasma concentrations were measured in guinea pigs administered either a single dose or multiple doses of this agent at 2.5, 5, and 10 mg/kg of body weight/day by subcutaneous injection. Immunosuppressed guinea pigs were inoculated withA. fumigatusAF293, and ASP9726 (2.5, 5, and 10 mg/kg/day), voriconazole (10 mg/kg by oral gavage twice daily), or caspofungin (3 mg/kg/day by intraperitoneal injection) was administered for 8 days. Changes in fungal burden were measured by enumerating CFU and by quantitative PCR of specimens from within the lungs, as well as by analysis of serum (1→3)-β-d-glucan and galactomannan. Lung histopathology was also evaluated. ASP9726 plasma concentrations increased in a dose-proportional manner, and the drug was well tolerated at each dose. Each dose of ASP9726, voriconazole, and caspofungin significantly reduced pulmonary fungal burden as measured by quantitative PCR and by determining (1→3)-β-d-glucan and galactomannan levels, but only voriconazole significantly reduced numbers of CFU. ASP9726 at 5 mg/kg also significantly improved survival. Histopathology demonstrated morphological changes in hyphae in animals exposed to ASP9726 and caspofungin, consistent with the activities of the echinocandins. These results suggest that ASP9726 may be efficacious for the treatment of invasive pulmonary aspergillosis.

PARTURITION IN THE GUINEA-PIG; PLASMA LEVELS OF STEROID HORMONES, STEROID-BINDING PROTEINS, AND OXYTOCIN, AND THE EFFECT OF CORTICOSTEROIDS, PROSTAGLANDINS AND ADRENOCORTICOTROPHIN

1974 ◽  
Vol 63 (3) ◽  
pp. 557-570 ◽  
Author(s):  
D. V. ILLINGWORTH ◽  
J. R. G. CHALLIS ◽  
N. ACKLAND ◽  
A. M. BURTON ◽  
R. B. HEAP ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Plasma Concentrations ◽  
Late Pregnancy ◽  
Maternal Plasma ◽  
Rapid Phase ◽  
Normal Delivery ◽  
Indwelling Catheters ◽  
Consistent Change ◽  
Significant Change ◽  
High Doses

SUMMARY Parturition in the guinea-pig is not preceded by any consistent change in the maternal plasma concentrations of progesterone, total unconjugated oestrogens or corticosteroids, or by a significant change in the concentration of progesterone-binding globulin (PBG). The onset of parturition was delayed by high doses of oestrogens (stilboestrol and oestradiol), but was not affected by oestriol or an antiserum raised against oestradiol. Premature parturition was achieved by the intra-carotid infusion of adrenocorticotrophin or prostaglandins (PGF2α, PGE2, I.C.I. 80,996) in conscious animals with indwelling catheters. I.C.I. 80,996, a potent analogue of PGF2α, induced parturition in all seven guinea-pigs treated; delivery occurred within 6 h of starting the infusion in six animals, and within 48 h in the seventh. The undesirable side-effects that accompanied treatment with PGF2α or PGE2 were not encountered with I.C.I. 80,996. Parturition induced experimentally resembled normal delivery but was not preceded by any significant change in the maternal levels of progesterone, total unconjugated oestrogens, corticosteroids, PBG or CBG in the circulation. Oxytocin was not detected until the delivery of the first foetus. Parturition was not induced by maternal or foetal injections of corticosteroids or dexamethasone. Earlier findings are confirmed that the foetal adrenal grows steadily throughout late pregnancy and, unlike the foetal lamb adrenal, undergoes no rapid phase of growth immediately before term. Foetal adrenal weight decreased relative to foetal body weight. The trigger for parturition in this species remains unidentified.

FOETAL AND MATERNAL PLASMA CONCENTRATIONS OF 13,14-DIHYDRO-15-OXO-PROSTAGLANDIN F IN THE MARE DURING LATE PREGNANCY AND AT PARTURITION

1978 ◽  
Vol 78 (2) ◽  
pp. 201-215 ◽  
Author(s):  
R. J. BARNES ◽  
R. S. COMLINE ◽  
L. B. JEFFCOTT ◽  
M. D. MITCHELL ◽  
P. D. ROSSDALE ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Maximum Concentration ◽  
Plasma Concentrations ◽  
Late Pregnancy ◽  
Maternal Plasma ◽  
Premature Delivery ◽  
Rapid Rise ◽  
Second Stage ◽  
Prostaglandin F ◽  
Venous Plasma

SUMMARY The concentrations of 13,14-dihydro-15-oxo-prostaglandin F (PGFM), the stable metabolite of prostaglandin F, were measured in the plasma of catheterized mares and foetuses and non-catheterized thoroughbred mares and ponies during the last months of gestation. The plasma concentration of PGFM increased gradually towards term in all groups of animals. During the operation for insertion of catheters, maternal and foetal concentrations of PGFM were high, but the values fell to basal levels 24–48 h after the operation. It was found that preoperative starvation (24 h) led to a rise in the concentration oef PGFM in th maternal plasma. The raised concentrations of PGFM during the operation were associated with low progestogen and high oestrogen concentrations in umbilical venous plasma. The subsequent survival period of the catheterized foal was inversely related to the maximum concentration of PGFM attained during the operation. Changes in the plasma concentration of PGFM were studied during normal parturition in thoroughbred mares, during oxytocin-induced delivery in non-catheterized ponies and during premature delivery or abortion in the catheterized animals. The greatest increase in the concentration of PGFM was seen in the thoroughbred animals during second-stage labour; oxytocin also resulted in a very rapid rise in the level of PGFM, which remained high until delivery. In the catheterized animals, the birth of live foetuses was associated with a rise in the concentration of PGFM in both foetal and maternal plasma during the last 2 h before delivery. Less consistent changes were found during abortion.

Changes in concentration of human atrial natriuretic peptide in normal pregnancy and toxaemia

1987 ◽  
Vol 114 (2) ◽  
pp. 325-328 ◽  
Author(s):  
Y. Otsuki ◽  
E. Okamoto ◽  
I. Iwata ◽  
E. Nishino ◽  
N. Mitsuda ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Atrial Natriuretic Peptide ◽  
Pregnant Women ◽  
Natriuretic Peptide ◽  
Plasma Concentrations ◽  
Normal Pregnancy ◽  
Maternal Plasma ◽  
Human Atrial Natriuretic Peptide ◽  
Atrial Natriuretic

ABSTRACT Changes in concentration of human atrial natriuretic peptide (hANP) in normal and toxaemic pregnancy were examined. The maternal plasma concentration of hANP increased gradually during normal pregnancy to a maximum of 20·0±2·4 pmol/l (mean ± s.e.m.) after week 36 of pregnancy. From week 20, the plasma concentrations of hANP were significantly higher than those in non-pregnant women (9·3±2·0 pmol/l). In toxaemia with hypertension, maternal plasma hANP levels were increased after week 26 of pregnancy (37·7±6·0 pmol/l) compared with those in normal gravida at the same time (17·1±1·6 pmol/l). Maternal plasma hANP levels in toxaemia only with oedema were not different from those in normal gravida. J. Endocr. (1987) 114, 325–328

scholarly journals Effect of pharmacological doses of ascorbic acid on the hepatic microsomal haemoproteins in the guinea-pig

1983 ◽  
Vol 49 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Judith L. Sutton ◽  
T. K. Basu ◽  
J. W. T. Dickerson
Keyword(s):  
Ascorbic Acid ◽  
Guinea Pig ◽  
Guinea Pigs ◽  
Sucrose Solution ◽  
Significant Rise ◽  
Mixed Function Oxidase ◽  
Ascorbic Acid Deficiency ◽  
Acid Deficiency ◽  
Specific Activities ◽  
Endogenous Substrates

1. Ascorbic acid deficiency results in a reduction in the activity of the hepatic mixed function oxidase systems in the guinea-pig. In this study, male Dunkin-Hartley guinea-pigs were given 0, 50, 100, 200 or 300 mg ascorbic acid/d in two equal doses in buffered sucrose solution (200 g/l) for 4 d. Controls received an equal volume of sucrose solution.2. A dose of 50 mg ascorbic acid/d resulted in a significant rise in the specific activities of both cytochromes P-450 and b5. At doses of 200 and 300 mg ascorbic acid/d the concentration of both haemoproteins was significantly lower than the control values. These effects were mirrored by total microsomal haem concentration.3. These results suggest that when given in large doses, ascorbic acid ceases to act simply as a vitamin and should be considered a drug competing for substrates and cofactors with co-administered drugs and endogenous substrates such as cholesterol.

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