Oestradiol and somatomedin-C influence body weight patterns in premenarchial rhesus monkeys housed outdoors

ABSTRACT The influence of gonadal status on the pattern of changes in body weight was examined in three groups of outdoor-housed premenarchial rhesus monkeys (Macaca mulatta) from 1 to 2 years of age. Gonadally intact (n=8) and ovariectomized oestradiol-treated females (n=5) gained significantly more weight than ovariectomized untreated females (n=5). The overall larger weight gains for the intact and ovariectomized oestradiol-treated groups were associated with significantly higher fasting levels of serum insulin. All subjects exhibited two periods of significant weight gain from 12 to 16 months of age between May and September and from 21 to 24 months of age between February and May. Serum GH and somatomedin-C levels were also raised during these periods of accelerated growth. Although the pattern of serum GH was similar among groups, serum somatomedin-C levels were significantly higher in both intact and ovariectomized oestradiol-treated subjects from 21 to 24 months of age, suggesting physiological levels of oestradiol may facilitate somatomedin-C production during periods of increased GH secretion. Thus, absolute changes in body weight in outdoor-housed premenarchial rhesus monkeys are influenced by gonadal status, possibly mediated through increases in serum insulin. Furthermore, dynamic changes in body weight occur during prepubertal development, with the largest increments associated with increased somatomedin-C levels at specific ages synchronized with natural changes in the environment. J. Endocr. (1984) 102, 311–317

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FURTHER OBSERVATIONS ON OOCYTE NUMBERS IN MATURE RHESUS MONKEYS (MACACA MULATTA)

Journal of Endocrinology ◽

10.1677/joe.0.0100284 ◽

1954 ◽

Vol 10 (3) ◽

pp. 284-290 ◽

Cited By ~ 15

Author(s):

S. H. GREEN ◽

S. ZUCKERMAN

Keyword(s):

Body Weight ◽

Menstrual Cycle ◽

Macaca Mulatta ◽

Rhesus Monkeys ◽

Stages Of Development ◽

The Right

SUMMARY An analysis of oocyte numbers in forty-two rhesus monkeys whose ovaries were removed on different days of the menstrual cycle showed (1) that the right and left ovaries usually contain about the same number of oocytes; (2) that oocyte numbers vary inversely with body weight; (3) that there are no significant differences in the total number of oocytes in the early, middle and last thirds of the cycle; and (4) that no constant relation exists between the proportion of follicles in different stages of development.

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Effects of Fetal or Maternal Hypophysectomy on Endocrine Organs and Body Weight in Infant Rhesus Monkeys (Macaca mulatta): With Particular Emphasis on Oogenesis

Biology of Reproduction ◽

10.1095/biolreprod16.2.216 ◽

1977 ◽

Vol 16 (2) ◽

pp. 216-227 ◽

Cited By ~ 69

Author(s):

BELA J. Gulyas ◽

GARY D. Hodgen ◽

William W. Tullner ◽

Griff T. Ross

Keyword(s):

Body Weight ◽

Macaca Mulatta ◽

Rhesus Monkeys ◽

Endocrine Organs ◽

Infant Rhesus

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Testosterone modulates growth hormone secretion at the hypothalamic but not at the hypophyseal level in the adult male rhesus monkey

Journal of Endocrinology ◽

10.1677/joe.0.1650337 ◽

2000 ◽

Vol 165 (2) ◽

pp. 337-344 ◽

Cited By ~ 4

Author(s):

SS Rizvi ◽

GF Weinbauer ◽

M Arslan ◽

CJ Partsch ◽

E Nieschlag

Keyword(s):

Growth Hormone ◽

Body Weight ◽

Rhesus Monkeys ◽

Hormone Secretion ◽

Plasma Concentrations ◽

Growth Hormone Secretion ◽

Qualitative Change ◽

Gh Secretion ◽

Significant Difference ◽

Male Rhesus

We investigated a possible modulation of growth hormone (GH) secretion by testosterone by measuring the growth hormone releasing hormone (GHRH)-stimulated and N-methyl-d,l-aspartic acid (NMA)-induced GH secretion in adult rhesus monkeys. Intact, orchidectomized and testosterone-substituted (testosterone enanthate 125 mg/week, i.m. for 5 weeks) orchidectomized monkeys (n=5) were used in the study. GHRH (25 microg/kg body weight) or NMA (15 mg/kg body weight) was infused through a Teflon cannula implanted in the saphenous vein. Sequential blood samples were collected 30-60 min before and 60 min after the injection of the neurohormone or the drug at 10-20-min intervals. All bleedings were carried out under ketamine hydrochloride anaesthesia (initial dose 5 mg/kg body weight i.m., followed by 2.5 mg/kg at 30-min intervals). The plasma concentrations of GH, testosterone and oestradiol (E(2)) were determined by using specific assay systems. Administration of GHRH elicited a significant increase in GH secretion in all three groups of animals. There was no significant difference in the responsiveness of pituitary somatotrophs to exogenous GHRH challenges between intact and orchidectomized monkeys and testosterone replacement in orchidectomized animals did not significantly alter the GHRH-induced GH response. The responsiveness of hypothalamic GHRH neurones apparently did undergo a qualitative change after orchidectomy, as GH response to NMA was less in orchidectomized animals than in intact monkeys. The responsiveness of GHRH neurones to exogenous NMA was restored and even potentiated when orchidectomized monkeys were treated with testosterone. Taken together, these findings suggest that testosterone does not affect the sensitivity of the pituitary somatotrophs to GHRH but stimulates the secretion of GH by modulation of the NMDA drive to GHRH neurones.

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Plasma growth hormone profile in acromegaly before and ten days after transsphenoidal surgery

Acta Endocrinologica ◽

10.1530/acta.0.1200113 ◽

1989 ◽

Vol 120 (1) ◽

pp. 113-120 ◽

Cited By ~ 7

Author(s):

Staffan Edén ◽

Bengt-Åke Bengtsson ◽

Kerstin Albertsson-Wikland ◽

Jörgen Elfversson ◽

Göran Lindstedt ◽

...

Keyword(s):

Transsphenoidal Surgery ◽

High Plasma ◽

Peripheral Vein ◽

Plasma Growth Hormone ◽

Somatomedin C ◽

Gh Secretion ◽

Hormone Profile ◽

Plasma Gh ◽

Serum Gh

Abstract. Profiles of plasma GH, plasma somatomedin-C and serum PRL concentrations as well as serum GH response to iv TRH were determined in 11 patients with acromegaly before and 10 days after surgery. Blood for profile determinations was drawn from a peripheral vein with a continuous withdrawal pump changing the recipient tube at 30-min intervals. Before surgery all patients had high plasma GH concentrations with irregular peaks and somatomedin-C concentrations were elevated. The response to TRH was abnormal in 8 patients. Three patients had slightly elevated PRL concentrations and one had high PRL concentration (6900 mU/l). Ten days after surgery GH concentrations were still high in 2 patients (>5 mU/l), as were somatomedin-C concentrations (3.2 and 2.4 U/l, respectively). In 3 patients basal GH concentrations were <5 mU/l and somatomedin-C concentrations were normal, but there were no major peaks in plasma GH concentrations. In 2 patients major peaks in GH concentrations appeared after surgery, but basal GH concentrations were 1.9 and 0.95 mU/l, respectively. One patient with hyperprolactinemia still had slightly elevated PRL concentration (486 mU/l), but the response to TRH was normalized. Finally, in 4 patients, mean GH concentrations were markedly reduced, somatomedin-C concentrations normalized and apparently normal plasma GH profiles appeared with low or undetectable basal levels separating major peaks. The results indicate that in some patients with acromegaly apparently normal GH secretion can be demonstrated 10 days postoperatively. Characterization of circadian GH rhythms during the early postoperative stage may contribute to the evaluation of the effect of surgery.

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Opioid modulation of FSH, growth hormone and prolactin secretion in the prepuberal gilt

Journal of Endocrinology ◽

10.1677/joe.0.1330013 ◽

1992 ◽

Vol 133 (1) ◽

pp. 13-19 ◽

Cited By ~ 9

Author(s):

C. R. Barb ◽

R. R. Kraeling ◽

G. B. Rampacek

Keyword(s):

Body Weight ◽

Prolactin Secretion ◽

Morphine Treatment ◽

Endogenous Opioid Peptides ◽

Endogenous Opioid ◽

Gh Secretion ◽

Age Related ◽

Artificial Cerebrospinal Fluid ◽

Serum Gh

ABSTRACT The role of endogenous opioid peptides (EOP) in modulating GH, prolactin (PRL) and FSH secretion was evaluated in prepuberal (P) gilts. In experiment I, P gilts received 1 (n = 2), 3 (n = 3) or 6 (n = 3) mg naloxone (NAL)/kg body weight i.v. Blood was collected every 15 min for 2 h prior to and 2 h after NAL and an additional 1 h after 100 μg gonadotrophinreleasing hormone (GnRH) i.v. In experiment II, P and mature (M) gilts were ovariectomized. Three weeks after ovariectomy, P and M gilts were injected twice a day for 10 days with either 0·85 mg progesterone (P4)/kg body weight or oil vehicle (V), resulting in the following groups: PP4 (n=11), PV (n = 10), MP4 (n=11) and MV (n=10). All gilts received 1 mg NAL/kg body weight on the last day of treatment. Blood samples were collected every 15 min for 4 h before and 2 h after NAL and an additional 1 h after 100μg GnRH i.v. In experiment III, six P and five M gilts were ovariectomized and surgically implanted with intracerebroventricular (i.c.v.) cannulae. Blood was collected every 15 min for 3 h before and 3 h after i.c.v. injection of 500 μg morphine in artificial cerebrospinal fluid (CSF) or 250 μl CSF. In experiment I, all doses of NAL failed to alter PRL secretion, while NAL increased (P<0·05) GH secretion in three out of eight gilts. However, NAL suppressed (P <0·05) FSH concentrations. In experiment II, NAL treatment increased (P<0·01) serum PRL concentrations and suppressed (P <0·05) FSH secretion in MP4 gilts. Serum PRL and FSH concentrations were unaltered by NAL in PV, PP4 and MV gilts. In experiment III, mean serum GH, PRL and FSH concentrations were unaffected by CSF injections. Morphine treatment evoked a rapid increase in serum GH and PRL concentrations in both P and M gilts. In contrast, morphine failed to influence FSH secretion in P gilts but did suppress FSH concentrations in M gilts. These data suggest that EOP receptors are functionally coupled to the GH and PRL secretory systems. There is an age-related change in EOP modulation of PRL secretion, while EOP modulation of FSH secretion is an age- and ovarian-dependent process. Journal of Endocrinology (1992) 133, 13–19

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Positive Correlation between IP-10 and IFN-γLevels in Rhesus Monkeys(Macaca mulatta)with Either Naturally Acquired or Experimental Infection ofMycobacterium tuberculosis

BioMed Research International ◽

10.1155/2017/5089752 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Fangui Min ◽

Ruike Wu ◽

Jinchun Pan ◽

Shuwu Huang ◽

Yinzhu Luo ◽

...

Keyword(s):

Macaca Mulatta ◽

Bovine Tuberculosis ◽

Rhesus Monkeys ◽

Nonhuman Primates ◽

Stimulation Index ◽

Diagnostic Biomarker ◽

Dynamic Changes ◽

Positive Correlation ◽

Infection Period ◽

Leucocyte Migration

Numerous studies identify that IP-10 and IFN-γare involved in leucocyte migration and activation and regarded as promising surrogate biomarkers in human and bovine tuberculosis infection, but there is lack of evidence for IP-10 in nonhuman primates. In this study, we directly determined IP-10 and IFN-γlevels in plasma from 30 healthy monkeys, 30 monkeys with naturally acquired tuberculosis, 4 monkeys experimentally infected with tuberculosis, and PPD stimulated whole blood of 14 monkeys with naturally acquired tuberculosis by ELISA. Higher plasma levels of IP-10 and IFN-γwere observed in natural tuberculosis monkeys than in healthy controls. The dynamic changes of plasma IP-10 and IFN-γin experimental infections showed consistent representation of a transient increase during the infection period. After PPD stimulation, release of IP-10 and IFN-γis significantly induced in natural tuberculosis monkeys, but the stimulation index of IP-10 was significantly lower than IFN-γ. Further analysis showed that positive correlation between IP-10 and IFN-γexisted in healthy and tuberculosis monkeys. Our findings support plasma IP-10 and IFN-γas biomarkers for monitoring ongoing inflammation of nonhuman primate tuberculosis, and IFN-γis a more valuable diagnostic biomarker.

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Nucleolar Segregation and Chronic Methanol Intoxication

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063718 ◽

1969 ◽

Vol 27 ◽

pp. 360-361

Author(s):

Julio H. Garcia ◽

Janice P. Van Zandt

Keyword(s):

Body Weight ◽

Methyl Alcohol ◽

Rhesus Monkeys ◽

Repeated Administration ◽

Serum Levels ◽

Methanol Intoxication ◽

Intragastric Tube ◽

Nucleolar Segregation

Repeated administration of methyl alcohol to Rhesus monkeys (Maccaca mulata) by intragastric tube resulted in ultrastructural abnormalities of hepatocytes, which persisted in one animal twelve weeks after discontinuation of the methyl alcohol regime. With dosages ranging between 3.0 to 6.0 gms. of methanol per kg. of body weight, the serum levels attained within a few hours averaged approximately 475 mg. per cent.

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