Relationship between Growth Hormone (GH) Pulses in the Peripheral Circulation and GH-Releasing Hormone and Somatostatin Profiles in the Cerebrospinal Fluid of Goats

Mogi, Kazutaka; Yonezawa, Tomohiro; Chen, Ding-Sheng; Li, Junyou; Suzuki, Masatoshi; Yamanouchi, Keitaro; Sawasaki, Toru; Nishihara, Masugi

doi:10.1292/jvms.66.1071

Cited by 22 publications

(30 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…GHRH, SRIF and NPY in CSF were assayed with commercial human GHRH, human SRIF and rat NPY RIA kits (RIK 8061, RIS 8001 and RIK 7180, respectively, Peninsula Laboratories, Belmont, CA, USA) according to the manufacturers' protocols using 50-μl CSF samples. Parallelism between standards for GHRH, SRIF and NPY assays and peptide levels in CSF samples has already been demonstrated in our previous studies [20,21]. The minimum assay sensitivity for GHRH was 5 pg/ml, and the intra-assay CVs for GHRH were 6.7%.…”

Section: Radioimmunoassayssupporting

confidence: 63%

“…These findings suggest that GHRH/SRIF interplay might be more complex than suggested by the classical hypothesis, at least in several species. We have examined the continuous profiles of several neuropeptides in cerebrospinal fluid (CSF) of the third ventricle in Shiba goats [20][21][22]. Measurement of hypothalamic neuropeptide levels, such as gonadotropin-releasing hormone levels, in the CSF of the third ventricle could be a good substitute for measurement in the portal blood [23][24][25].…”

mentioning

confidence: 99%

See 1 more Smart Citation

Effects of Estrogen on Growth Hormone Pulsatility in Peripheral Blood and Neuropeptide Profiles in the Cerebrospinal Fluid of Goats

Yonezawa

Mogi

et al. 2011

Journal of Reproduction and Development

Self Cite

View full text Add to dashboard Cite

Abstract. We previously reported that growth hormone (GH) pulses were negatively associated with neuropeptide Y (NPY) profiles in cerebrospinal fluid (CSF) of the third ventricle of Shiba goats. In addition, while most GH pulses were coincident with GH-releasing hormone (GHRH) pulses, there was no correlation between GH and somatostatin (SRIF) levels. The present study was performed to elucidate the relationship between GH pulses and these neuropeptide levels in CSF when estradiol (1.0 mg/head) was subcutaneously administered to ovariectomized goats. CSF and plasma samples were collected every 15 min for 18 h (from 6 h before to 12 h after injection). GH levels in peripheral blood and GHRH, SRIF and NPY levels in CSF were measured by radioimmunoassay. Pulse/trough characteristics and correlations were assessed by the ULTRA algorithm and cross-correlation analysis. Before estradiol was injected, significant coincidence was found between GHRH pulses and GH pulses, and negative coincidence was found between NPY troughs and GH pulses. Six to 12 h after estradiol injection, the amplitude and area under the curve (AUC) of the GH pulses were markedly increased. The duration and AUC of the GHRH pulses in the CSF were also increased, and stronger synchrony of GHRH with GH was observed. In contrast, the baseline of NPY was significantly decreased, and the negative correlation between the GH pulses and NPY troughs disappeared. The parameters of SRIF troughs were not clearly changed. These observations suggest that estrogen enhances the pattern of secretion of GH in the goat via enhancement of GHRH pulses and decrease of NPY levels. Key words: Estrogen, Growth hormone, Growth hormone-releasing hormone, Neuropeptide Y, Somatostatin (J. Reprod. Dev. 57: [280][281][282][283][284][285][286][287] 2011) rowth hormone (GH) is secreted in a pulsatile fashion in various mammalian species, and this plays an important role in the regulation of somatic growth and metabolism [1][2][3]. Lipolysis is stimulated by high-amplitude GH pulses, and fat accumulation occurs during continuous low GH secretion [1][2][3]. Since the Shiba goat has a distinct profile of GH pulsatility at regular intervals [4,5], it might be a good experimental model for study of the mechanisms of GH pulse generation. A previous study also demonstrated that the GH secretory pattern varies during the estrous cycle according to the changes in plasma sex steroid levels [5]. In particular, estrogen markedly enhanced the amplitude and area under the curve (AUC) of GH pulses, which has also been observed in other experiments in sheep [6,7] and baboons [8]. Therefore, lipolysis could be stimulated during the estrous phase when the GH pulses were robust. In addition, it was reported that GH release could contribute to follicular development [9] and could act as a cogonadotropin to induce ovulation [10]. Taken together, enhancement of GH pulse amplitude by estrogen may yield an appropriate metabolic milieu for the reproductive stage [1,5,11]. Nevertheless, how sex steroids ...

show abstract

Section: Radioimmunoassayssupporting

confidence: 63%

mentioning

confidence: 99%

Effects of Estrogen on Growth Hormone Pulsatility in Peripheral Blood and Neuropeptide Profiles in the Cerebrospinal Fluid of Goats

Yonezawa

Mogi

et al. 2011

Journal of Reproduction and Development

Self Cite

View full text Add to dashboard Cite

show abstract

“…In the males, GHRH values increased in native hair and Honamlı goats after the 4th and 8th month, respectively. Considering the data of GH and GHRH together, it could be concluded that these parameters revealed parallel courses and they appear to correspond with those observed in previous studies (Mogi et al 2004, Yonezawa et al 2011). There were significant GHRP increases in Honamlı bucks and in the females of the both breeds after 4 months period.…”

Section: Discussionsupporting

confidence: 87%

Levels of hormones and cytokines associated with growth in Honamlı and native hair goats

Devrim¹,

Elmaz²,

Mamak³

et al. 2015

Polish Journal of Veterinary Sciences

View full text Add to dashboard Cite

This study was designed to assess alterations of hormone and cytokine levels associated with growth period during puberty in Honamlı goats which were identified as a new goat breed and had one of the highest meat production potential among the other goat breeds in Turkey. Honamlı goats are originated from native hair goats, so parallel studies of sampling and analyzing were conducted also in native hair goats which have moderate meat production. Blood serum samples of Honamlı (n=90) and native hair goats (n=90) were obtained from the pure herds in Korkuteli and Ka districts of Anatolia. Concentrations of growth hormone (GH), myostatin (MSTN), insulin-like growth factor (IGF), growth hormone releasing hormone (GHRH), growth hormone releasing peptide (GHRP), leptin, transforming growth factor-betal (TGF-β1) and vascular endothelial cell growth factor (VEGF) levels were measured by ELISA in each breed in the age groups of 4, 8 and 12 months. The present results indicate interesting correlations among the age groups and all the examined hormone and cytokine parameters exhibited significant (P<0.05 and P<0.001) differences. The parameters investigated were usually begun to increase after 4 months of age in the both breeds and sexes. Therefore, this paper supported the view that the beginning of hormonal alterations of goats could occur at 4th month of age. The results reported here emphasize the primary role played by GH, MSTN, IGF-1, leptin, GHRH, GHRP, TGF-βi and VEGF in the first year growth period of goats.

show abstract

“…Injections of NPY led to a suppression of GH lasting, after a delay of about 30-60 min, up to 2 h. They further established a direct link between NPY axons and SRIF neurons by receptor analysis. In the goat, which seems to have a GH profile similar to the rat but with a periodicity of w5 h, and the same effect of NPY administration was observed (Mogi et al 2004). Moreover, Pierroz et al (1996) have shown that chronic i.c.v.…”

Section: Ghrelin-npy Pathwaymentioning

confidence: 75%

Interactions of ghrelin signaling pathways with the GH neuroendocrine axis: a new and experimentally tested model

Wagner¹,

Caplan²,

Tannenbaum³

2009

Journal of Molecular Endocrinology

View full text Add to dashboard Cite

Growth hormone (GH) is secreted in a pulsatile fashion from the pituitary gland into the circulation. Release is governed by two hypothalamic neuropeptides, growth hormone-releasing hormone (GHRH) and somatostatin (SRIF), resulting in secretion episodes with a periodicity of 3 . 3 h in the male rat. Ghrelin is an additional recently identified potent GH-secretagogue. However, its in vivo interactions with the GH neuroendocrine axis remain to be elucidated. Moreover, two different sites of ghrelin synthesis are involved, the stomach and the hypothalamus. We used our previously developed core model of GH oscillations and added the sites of ghrelin action at the pituitary and in the hypothalamus. With this extended model, we simulated the effects of central and peripheral ghrelin injections, monitored the GH profile and compared it with existing experimental results. Systemically administered ghrelin elicits a GH pulse independent of SRIF, but only in the presence of GHRH. The peripheral ghrelin signal is mediated to the brain via the vagus nerve, where it augments the release of GHRH and stimulates the secretion of neuropeptide-Y (NPY). By contrast, centrally administered ghrelin initiates a GH pulse by increasing the GHRH level and by antagonizing the SRIF block at the pituitary. In addition, NPY neurons are activated, which trigger a delayed SRIF surge. The major novel features of the present model are a) the role played by NPY, and b) the dissimilar functions of ghrelin in the hypothalamus and at the pituitary. Furthermore, the predictions of the model were experimentally examined and confirmed.

show abstract

Relationship between Growth Hormone (GH) Pulses in the Peripheral Circulation and GH-Releasing Hormone and Somatostatin Profiles in the Cerebrospinal Fluid of Goats

Cited by 22 publications

References 52 publications

Effects of Estrogen on Growth Hormone Pulsatility in Peripheral Blood and Neuropeptide Profiles in the Cerebrospinal Fluid of Goats

Effects of Estrogen on Growth Hormone Pulsatility in Peripheral Blood and Neuropeptide Profiles in the Cerebrospinal Fluid of Goats

Levels of hormones and cytokines associated with growth in Honamlı and native hair goats

Interactions of ghrelin signaling pathways with the GH neuroendocrine axis: a new and experimentally tested model

Contact Info

Product

Resources

About