A central action of α-melanocyte-stimulating hormone on serum levels of LH and prolactin in rats

1990 ◽  
Vol 124 (1) ◽  
pp. 127-132 ◽  
Author(s):  
T. Scimonelli ◽  
M. E. Celis
Keyword(s):  
Dopaminergic System ◽  
Single Injection ◽  
Serum Levels ◽  
Inhibitory Effect ◽  
Ovariectomized Rats ◽  
Serum Concentrations ◽  
Prolactin Release ◽  
Blood Samples ◽  
Melanocyte Stimulating Hormone ◽  
Tuberoinfundibular Dopaminergic System

ABSTRACT We have investigated the effect of administration of α-MSH into the median eminence (ME) of rats on the release of LH and prolactin. Continuous infusion of α-MSH (0·5 μg/h) into the ME from the afternoon of the second day of dioestrus and over the 24 h of pro-oestrus inhibited the preovulatory LH and prolactin surge and the occurrence of ovulation. This inhibitory effect on LH and prolactin release was also observed in chronically ovariectomized rats given a single injection of α-MSH (1 μg/μl per rat) into the ME (blood samples were collected 0,20,60,90,105 and 120 min after injection). The intraperitoneal injection of the dopamine receptor blocker, haloperidol (2 mg/kg), 30 min before the injection of α-MSH into the ME prevented the inhibitory effect of α-MSH on the release of LH and prolactin. These results suggest that hypothalamic α-MSH might be involved in the regulation of LH and prolactin release via the tuberoinfundibular dopaminergic system and that this system also modifies the serum concentrations of α-MSH. Journal of Endocrinology (1990) 124, 127–132

A possible dual regulation of prolactin release by the serotoninergic system in rats at pro-oestrus and during late pregnancy: role of ovarian hormones

1987 ◽  
Vol 112 (3) ◽  
pp. 367-374 ◽  
Author(s):  
G. A. Jahn ◽  
R. P. Deis
Keyword(s):  
Serotonin Receptor ◽  
Late Pregnancy ◽  
Inhibitory Effect ◽  
Ovariectomized Rats ◽  
Serum Prolactin ◽  
Serotoninergic System ◽  
Serum Concentrations ◽  
Prolactin Release ◽  
Treatment Administration ◽  
Significant Release

ABSTRACT The effect of para-chlorophenylalanine (pCPA), an inhibitor of serotonin synthesis, on prolactin release was studied in rats on the day of pro-oestrus and at the end of pregnancy (day 19). The surges of prolactin normally seen in the afternoon of pro-oestrus in intact rats and in rats ovariectomized on dioestrous day 2 and primed with oestrogen were significantly inhibited by pCPA treatment. Administration of 5-hydroxy-tryptophan reversed the inhibitory action of pCPA on prolactin release. Treatment with progesterone also completely reversed the inhibitory effect of pCPA on prolactin release in pro-oestrous rats and partially reversed it in ovariectomized oestrogen-treated rats. Ovariectomy on day 19 of pregnancy induced a significant release of prolactin 12 and 24 h later. Administration of pCPA on day 18 of pregnancy produced a marked increase in serum concentrations of prolactin on days 19 and 20 in rats left intact or ovariectomized on day 19. Administration of 5-hydroxy-tryptophan significantly reversed this stimulatory effect of pCPA on prolactin release but did not modify the release of prolactin induced by ovariectomy. Methiothepin (1-[10,11-dihydro-8-(methylthio) <b,f> thiepin-10,41]-4-methylpiperazine maleate), a serotonin receptor blocker, also induced a significant increase in serum concentrations of prolactin on day 20 of pregnancy in rats left intact or ovariectomized on day 19. These results suggest the existence of different serotoninergic actions in the regulation of prolactin release at pro-oestrus and in late pregnancy. Serotonin facilitates the surges of serum prolactin released at pro-oestrus and in ovariectomized rats treated with oestrogen; progesterone enhances this effect. On the other hand, during late pregnancy, when progesterone tonically inhibits prolactin release, serotonin inhibits the release of prolactin. J. Endocr. (1987) 112, 367–374

scholarly journals Serum Levels of Neuropeptides in Cows with Left Abomasal Displacement

2018 ◽  
Vol 5 (4) ◽  
pp. 103
Author(s):  
Marlene Sickinger ◽  
Joachim Roth ◽  
Klaus Failing ◽  
Axel Wehrend
Keyword(s):  
Substance P ◽  
Dairy Cows ◽  
Vasoactive Intestinal Polypeptide ◽  
Serum Levels ◽  
Common Disease ◽  
Healthy Controls ◽  
Serum Concentrations ◽  
Blood Samples ◽  
Breed Difference ◽  
Abomasal Displacement

Abomasal displacement (AD) to the left is a common disease in high-yielding dairy cows after parturition. In view of the previously reported changes in tissue neuropeptide concentrations in cows with AD, the primary aim of this study was to evaluate the effect of AD and breed on serum neuropeptide concentrations. For this purpose, blood samples of 33 German Holstein (GH) cows with AD, 36 healthy controls (GH), and 32 healthy German Fleckvieh (GF) cows were collected, and concentrations of substance P (SP), vasoactive intestinal polypeptide (VIP), and interleukin1β (IL-1β) were measured via commercially available ELISA kits. To examine the effect of AD, we compared GH cows with and without AD and observed no significant effects of AD on SP, VIP, or Il-1 β concentrations. To evaluate the effect of breed, we compared healthy GH with healthy GF cows and detected markedly higher VIP serum levels in the healthy GF cows (p < 0.01). No significant differences in SP or IL-1β were detected. According to our results, there seems to be no effect of AD on the serum concentrations of SP, VIP, or IL-1 β. In contrast, there seems to be a breed difference concerning serum VIP concentrations.

scholarly journals Investigations on the Effects of Different Calcium Supply Exceeding the Requirements on Mineral Serum Concentrations and Bone Metabolism in Young Warmblood Stallions

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2439
Author(s):  
Dana Carina Schubert ◽  
Lisa-Theresa Neustädter ◽  
Manfred Coenen ◽  
Christian Visscher ◽  
Josef Kamphues
Keyword(s):  
Trace Elements ◽  
Bone Metabolism ◽  
Bone Markers ◽  
Serum Levels ◽  
Serum Concentrations ◽  
Feeding Trial ◽  
Blood Samples ◽  
Mineral Supplements ◽  
High Calcium ◽  
Calcium Supply

Since mineral supplements for horses commonly contain macro minerals, although the requirement for such is usually covered by roughage-based diets, the aim of this study was to investigate the effects of different dietary calcium levels on mineral serum concentrations and bone metabolism. The trial was conducted in 30 young warmblood stallions (2–3 years) that were divided into two groups for a five-month feeding trial. The groups were fed a hay- and oat-based diet and were either supplied with high (Ca-High) or moderate (Ca-Moderate) calcium excess. While in Ca-High calcium supply was about 2–2.5-fold of the requirement, in Ca-Moderate calcium requirements were slightly surpassed (1.5–1.6-fold). In order to monitor the effects of the different calcium supply, blood samples were taken during the trial and analysed for levels of macro and trace elements as well as concentrations of two bone markers. In Ca-Moderate a trend towards higher phosphorus serum levels compared to Ca-High was observed which was significant at the end of the trial (p = 0.0002). Furthermore, results showed no influence of the diet on bone markers. Results support the idea that forage-based rations for horses do not necessarily have to be supplemented with macro minerals but with trace elements.

Traditional Chinese Whole-Body Acupuncture Mobilizes CD133(+)CD34(−) Cells

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 5405-5405
Author(s):  
Sonja Moldenhauer ◽  
Miriam Burgauner ◽  
Rainer Hellweg ◽  
Andreas Lun ◽  
Holger Kiesewetter ◽  
...  
Keyword(s):  
Serum Levels ◽  
Whole Body ◽  
Granulocyte Colony Stimulating Factor ◽  
Serum Concentrations ◽  
Spinal Cord Lesions ◽  
Blood Samples ◽  
Cd34 Cells ◽  
Body Acupuncture ◽  
Study Participants ◽  
Stimulating Factor

Abstract The objective of this study was to analyze the effects of traditional Chinese acupuncture for spinal cord lesions on the mobilization of stem cells. Therefore, 14 healthy study participants were acupunctured and gave blood samples before, immediately after as well as 24 and 48 hours after acupuncture. At these time points, the frequency of CD133, CD34, CD4, CD14, CD19 and CD45 positive cells were determined by flow cytometry. Furthermore, serum concentrations of matrix metalloproteinases (MMP) 8 and 9, brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), stroma-derived factor (SDF) 1 and granulocyte-colony stimulating factor (G-CSF) were measured by enzyme-linked immunosorbent assays. CD133(+)34(−) cells were significantly increased 48 hours after acupuncture (29.1±5.8% versus 11.4±4.8%, p= 0.015), which was paralleled by significant decreases of BDNF (7.5±1 ng/ml versus 10.8±1.6 ng/ml, p= 0.013) and MMP-9 serum levels (46.4±2.6ng/ml versus 42.5±2.4 ng/ml, p= 0.009). Values in non-treated controls were not affected. No changes in SDF-1, NGF, interleukin-6 and G-CSF concentrations occurred. In conclusion, acupuncture does mobilize non-hematopoietic CD133(+) cells.

INDUCTION OF SEXUAL RECEPTIVITY IN OVARIECTOMIZED RATS BY PULSE ADMINISTRATION OF OESTRADIOL-17β

1981 ◽  
Vol 89 (1) ◽  
pp. 55-62 ◽  
Author(s):  
P. SÖDERSTEN ◽  
P. ENEROTH ◽  
S. HANSEN
Keyword(s):  
Single Injection ◽  
Serum Levels ◽  
Female Rats ◽  
Ovariectomized Rats ◽  
Sexual Receptivity ◽  
Behavioural Responses ◽  
Time Points ◽  
Progesterone Treatment ◽  
Oestradiol Benzoate ◽  
Stimulation Of

Constant-release implants filled with oestradiol-17β induced sexual receptivity in ovariectomized rats in response to progesterone treatment if they were implanted 32 h before behavioural testing. A 20 h period of exposure to oestradiol, by implantation 32 h before testing and removal of the implants 20 h later, was sufficient for induction of the behaviour. The exposure time necessary for behavioural responses could be further reduced to two 4 h periods, between 32 and 28 h and between 16 and 12 h, before testing. Serum levels of oestradiol were raised within 1 h of oestradiol implantation and declined rapidly after implant removal. A single injection of oestradiol benzoate was much more potent than a single injection of oestradiol in inducing sexual receptivity in ovariectomized rats, but this difference in potency was reversed if two appropriately timed injections were given. Oestrone- or oestriol-filled implants were relatively ineffective in inducing sexual receptivity. It is suggested that oestradiol has to be present at crucial time points to prepare an ovariectomized rat to respond behaviourally to progesterone treatment and that oestradiol is the principal oestrogen in the stimulation of sexual behaviour in female rats.

Changes of Serum Concentrations of Alkaline Phosphatase and Metalloproteinase-9 in an Ovariectomized Wistar Rat Model of Osteoporosis

2017 ◽  
Vol 10 (1) ◽  
pp. 32-36 ◽  
Author(s):  
Armine V. Grigoryan ◽  
Aneliya A. Dimitrova ◽  
Krasimir G. Kostov ◽  
Adelaida L. Russeva ◽  
Milena A. Atanasova ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Bone Structure ◽  
Elevated Serum ◽  
Wistar Rat ◽  
Serum Levels ◽  
Reproductive Age ◽  
Ovariectomized Rats ◽  
Control Group ◽  
Bone Homeostasis ◽  
Serum Concentrations

SummaryOsteoporosis is a systemic skeletal disease characterized by decreased bone mass, destruction of the microarchitectonics of bone structure and a high risk for fracture. One of the criteria for altered bone homeostasis includes the changes in serum levels of alkaline phosphatase (ALP) and the activity of matrix metalloproteinases (MMPs). The purpose of this study was to determine the serum concentrations of calcium (Ca2+), phosphorus (P), magnesium (Mg2+), alkaline phosphatase (ALP) and MMP-9 in ovariectomized rats. We used 35 female Wistar rats at reproductive age (2 months) divided into 2 groups: a control group (G1-SHAM) – 20 animals subjected to “false” ovariectomy and placebo-operation, and an ovariectomized group (G2-OVX) – 15 animals subjected to bilateral ovariectomy. Blood was collected from the abdominal aorta for testing levels of Ca2 +, P, Mg2+, ALP and MMP-9. No statistically significant differences in serum concentrations of Ca2+, P and Mg2+were found between G2 and G1 (p>0.05). The values of ALP and MMP-9 in rats of G2 were statistically significantly increased, as compared to G1 (p<0.05). The serum activity of ALP, which is a marker for bone formation, was increased in OVX-induced osteoporosis. Elevated serum MMP-9 levels in G2 confirmed the hypothesis that it is a marker for osteoclast activity.

SERUM CONCENTRATIONS OF LH, FSH AND PROLACTIN IN OVARIECTOMIZED EWES FOLLOWING TREATMENT WITH ANDROGENS OR ESTROGENS

1984 ◽  
Vol 64 (1) ◽  
pp. 171-175
Author(s):  
B. E. HOWLAND ◽  
L. M. SANFORD ◽  
W. M. PALMER
Keyword(s):  
Luteinizing Hormone ◽  
Testosterone Propionate ◽  
Single Injection ◽  
Follicle Stimulating Hormone ◽  
Serum Levels ◽  
Estradiol Benzoate ◽  
Serum Concentrations ◽  
Hormone Levels ◽  
Key Words Androgens ◽  
Estradiol 17Β

The effect of a single injection of dihydrotestosterone, testosterone, testosterone propionate, estradiol-17β or estradiol benzoate on serum levels of luteinizing hormone, follicle stimulating hormone and prolactin was studied in ovariectomized ewes. Luteinizing hormone levels increased following treatment with E, EB or TP, prolactin levels increased following treatment with E, EB, T or TP while FSH levels decreased after treatment with either E or EB. Free steroids appeared to produce earlier responses in hormone levels than the corresponding esters. Key words: Androgens, estrogens, gonadotropins, prolactin, ewes.

EFFECTS OF PINEALECTOMY ON THE RAT OESTROUS CYCLE AND PITUITARY GONADOTROPHIN RELEASE

1976 ◽  
Vol 69 (1) ◽  
pp. 67-75 ◽  
Author(s):  
C. A. BLAKE
Keyword(s):  
Pineal Gland ◽  
Oestrous Cycle ◽  
Ovariectomized Rats ◽  
Prolactin Release ◽  
Medial Basal Hypothalamus ◽  
Blood Samples ◽  
Serum Lh ◽  
Oestradiol Benzoate ◽  
Lh Release ◽  
Permissive Role

SUMMARY In 4-day cyclic rats kept in a room with the lights on from 05.00 to 19.00 h, sham pinealectomy or pinealectomy on the morning of pro-oestrus did not alter the length of the oestrous cycle for 44 days or the time and magnitude of the rises in LH, FSH and prolactin in the circulation in the afternoon on pro-oestrous days 0, 20 or 44. On day 45, the light schedule was set forward 4 h to run from 09.00 to 23.00 h. The rats continued to have seven additional consecutive 4-day oestrous cycles. On day 27 after the resetting of the light schedule, the pro-oestrous rises in serum LH, FSH and prolactin were delayed 4 h in all rats and a normal quota of eggs was ovulated that night. Other 4- and 5-day cyclic rats which had been made persistently oestrous by anterior deafferentation of the medial basal hypothalamus (AC) underwent pinealectomy. These AC-pinealectomized rats were ovariectomized 60 days later and histological examination of the ovaries revealed no evidence of recent ovulation. Five to six weeks after ovariectomy, sequential blood samples were withdrawn through indwelling atrial cannulas in the AC-pinealectomized-ovariectomized rats and in ovariectomized, pinealectomized-ovariectomized and AC-ovariectomized rats. Regular pulsatile rhythms in plasma LH were measured in all rats. Subcutaneous injection of 50 μg oestradiol benzoate in oil lowered plasma LH levels in all four groups but caused an LH surge in the afternoon 2 days later only in the ovariectomized and pinealectomized-ovariectomized rats. The results indicate that the pineal gland in rats kept on a 14 h light: 10 h darkness schedule does not play an active or permissive role in the timing or magnitude of LH, FSH or prolactin release at pro-oestrus, the length of the oestrous cycle, or LH release in ovariectomized rats.

scholarly journals Kisspeptin serum levels in acute myocardial infarction patients and healthy individuals

2018 ◽  
Vol 5 (3) ◽  
pp. 2111-2118 ◽  
Author(s):  
Mohammad Shojaei ◽  
Saeideh Erfanian ◽  
Abdolreza Sotoodeh Jahromi ◽  
Naeimeh Yusefi ◽  
Abdolhossein Madani ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Serum Levels ◽  
Serum Concentrations ◽  
Healthy Individuals ◽  
Control Groups ◽  
Blood Samples ◽  
St Segment Elevation ◽  
St Segment ◽  
And Control

Introduction: Acute myocardial infarction (AMI) is a leading cause of mortality worldwide for which several risk factors have been identified. Kisspeptin is a multifunctional peptide observed in atherosclerotic plaques. This study aimed to compare kisspeptin serum levels in AMI patients and healthy individuals. Methods: This case-control study was conducted on patients visiting the Cardiology department of Peymanieh Hospital, Jahrom University of Medical Sciences, Iran. Participants were randomly divided into a case and a control groups; the former consisting of 90 AMI patients and the latter of 90 healthy individuals with no cardiac diseases. Blood samples were collected from the participants who also completed the given questionnaire. The enzyme-linked immunosorbent assay (ELISA) test was used to determine kisspeptin levels following serum separation from collected blood samples. Data analysis was performed in SPSS-19 using descriptive (mean and standard deviation) and analytical (The Mann-Whitney U test) statistical tests. Results: The mean age of treatment and control groups was 60.91 and 61.72 years, respectively. The majority (73.3%) of participants in this study were men. Kisspeptin serum concentrations were demonstrated to be significantly lower in the case group than the control group (P<0.001). The results of Mann-Whitney U test revealed that kisspeptin serum concentrations of case and control groups did not have a significant relationship with such variables as gender, smoking, and ST-segment elevation and non-ST-segment elevation (P>0.05). Conclusion: The results revealed that kisspeptin serum concentrations of AMI patients were significantly lower than those of healthy individuals. Accordingly, kisspeptin deficiency appears to be a risk factor for AMI. However, due to the multifunctional nature of this peptide, further studies are necessary to discover its precise mechanism of action.

VARIATIONS IN PLASMA CONCENTRATIONS OF α-MELANOCYTE-STIMULATING HORMONE DURING THE OESTROUS CYCLE OF THE RAT AND AFTER ADMINISTRATION OF OVARIAN STEROIDS

1981 ◽  
Vol 88 (1) ◽  
pp. 73-80 ◽  
Author(s):  
A. J. THODY ◽  
C. A. WILSON ◽  
P. D. LUCAS ◽  
C. FISHER
Keyword(s):  
Single Injection ◽  
Dark Period ◽  
Plasma Concentrations ◽  
Oestrous Cycle ◽  
Ovariectomized Rats ◽  
Ovarian Steroids ◽  
Melanocyte Stimulating Hormone ◽  
Oestradiol Benzoate ◽  
Stimulating Hormone

Plasma concentrations of α-melanocyte-stimulating hormone (α-MSH) were measured by radioimmunoassay at various times during the oestrous cycle of the rat. Variations in plasma α-MSH concentrations occurred throughout the oestrous cycle. Plasma α-MSH concentrations were low during the day of dioestrus 1 and rose during the evening reaching peak levels at around 02.00 and 06.00 h on dioestrus 2. Plasma α-MSH concentrations then fell and remained low throughout the rest of dioestrus 2. A different pattern was observed during pro-oestrus and oestrus. On those days peak α-MSH concentrations occurred during the morning and persisted until the onset of the dark period at around 17.00 h. Plasma α-MSH concentrations in ovariectomized rats were found to be increased 24 h after administration of a single injection of oestradiol benzoate and at 12 and 36 h after a single injection of progesterone. It is suggested that these ovarian steroids may influence the rhythm in plasma α-MSH concentration that occurs during the oestrous cycle.

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