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Besides LH and FSH also growth factors like IGF and GH are important to get ur balls back...
During PCT the levels of igf/gh/t3 are lower then normal and this can be one of the bottlenecks during PCT. So adding those during pct can greatly help you to recover from your cycle. Would also great to add hcg(lh) or even better hmg(lh+fsh)..
Below you can see a few studies where the importance of growth factors is given:
-1 Grizard G.
Laboratoire de Biologie de la Reproduction, Faculte de Medecine, Clermont-Ferrand.
Many in vitro and in vivo studies have demonstrated a presence of IGF-I in the testis. Testicular production of IGF-I and its mRNA is stimulated largely by gonadotropins; FSH acts on Sertoli cells while LH acts on Leydig cells. A regulation by local factors is also demonstrated; the role of GH remains unclear. In the testis, IGF-I has various effects but we only focussed this review on Leydig cells. Specific receptors have been characterized on these cells. They are up-regulated by LH/hCG (at the transcriptional level) and down regulated by IGF-I. The effect of GH is depend on the experimental models used. In addition in this paper, we have shown in adult rats that the IGF-I level in the testicular interstitial fluid and the IGF-I receptors on Leydig cells are modified by fasting. Both in vivo and in vitro, IGF-I increased LH/hCG receptors and the steroidogenic response to hCG by a mechanism which is poorly understood yet.PMID: 7994317 [PubMed - indexed for MEDLINE]
-2 Chandrashekar V, Bartke A.
Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL 62901-6512, USA. shekar@siu.edu
There is unequivocal evidence that the biosynthesis and secretion of gonadotropins by the pituitary gland is controlled by the hypothalamic GnRH and the function of the testis is mainly regulated by FSH and LH. However, a number of investigations have suggested the role of other hormones/factors, including insulin-like growth factor-I (IGF-I) in the control of pituitary and gonadal functions. The role of growth hormone (GH) and IGF-I is poorly investigated in humans. In animals with altered IGF-I secretion, the gonadotropin and androgen secretions are affected. Similarly, there is evidence that fertility, the onset of puberty and coïtusual maturation are affected in some patients with Laron syndrome and in acr*****ly. In this minireview, we have presented some data obtained in humans and also included results from several experimental models with altered GH/IGF-I secretion, in the hope that the results from animals will possibly help in understanding the important role of IGF-I in the control of neuroendocrine-testicular function in humans.
-3 Spiteri-Grech J, Nieschlag E.
Institute of Reproductive Medicine, The University, Munster, FRG.
Animal experiments and clinical studies on the interactions between growth hormone (GH) and the male hypothalamic-pituitary-gonadal axis have predominantly concentrated on GH and coïtus steroid interactions in the regulation of growth and development, or on the metabolic effects of GH. In contrast, little attention has been paid to the possible effects of GH on spermatogenesis, although the first report dealing with this topic was published almost 30 years ago. The interactions of GH and its main mediator, insulin-like growth factor I (IGF-I), with the hypothalamic-pituitary-gonadal axis, and their role in spermatogenesis have recently been investigated using in vitro systems and different animal models (mice and rats). Using Leydig and Sertoli cell cultures, complex interactions between GH/IGF-I and the gonadotropins affecting differentiated cell functions, e.g. steroidogenesis and cell division, have been demonstrated at the cellular level. In vivo studies using immature and mature hypophysectomized rats and GH-deficient mutant male mice and rats indicate that IGF-I can play an important role in the regulation of steroidogenesis and spermatogenesis. Furthermore, although follicle-stimulating hormone and luteinizing hormone are the major regulators of testicular IGF-I production, GH may play an indirect role by potentiating the actions of the gonadotropins in regulating testicular IGF-I content. A large proportion of men presenting at male-infertility clinics are diagnosed as having idiopathic infertility. Further studies are necessary to investigate whether defects associated with GH and/or IGF-I effects in the testis are the cause of male infertility in a small group of these patients.
PMID: 1295809 [PubMed - indexed for MEDLINE]
Besides LH and FSH also growth factors like IGF and GH are important to get ur balls back...
During PCT the levels of igf/gh/t3 are lower then normal and this can be one of the bottlenecks during PCT. So adding those during pct can greatly help you to recover from your cycle. Would also great to add hcg(lh) or even better hmg(lh+fsh)..
Below you can see a few studies where the importance of growth factors is given:
-1 Grizard G.
Laboratoire de Biologie de la Reproduction, Faculte de Medecine, Clermont-Ferrand.
Many in vitro and in vivo studies have demonstrated a presence of IGF-I in the testis. Testicular production of IGF-I and its mRNA is stimulated largely by gonadotropins; FSH acts on Sertoli cells while LH acts on Leydig cells. A regulation by local factors is also demonstrated; the role of GH remains unclear. In the testis, IGF-I has various effects but we only focussed this review on Leydig cells. Specific receptors have been characterized on these cells. They are up-regulated by LH/hCG (at the transcriptional level) and down regulated by IGF-I. The effect of GH is depend on the experimental models used. In addition in this paper, we have shown in adult rats that the IGF-I level in the testicular interstitial fluid and the IGF-I receptors on Leydig cells are modified by fasting. Both in vivo and in vitro, IGF-I increased LH/hCG receptors and the steroidogenic response to hCG by a mechanism which is poorly understood yet.PMID: 7994317 [PubMed - indexed for MEDLINE]
-2 Chandrashekar V, Bartke A.
Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL 62901-6512, USA. shekar@siu.edu
There is unequivocal evidence that the biosynthesis and secretion of gonadotropins by the pituitary gland is controlled by the hypothalamic GnRH and the function of the testis is mainly regulated by FSH and LH. However, a number of investigations have suggested the role of other hormones/factors, including insulin-like growth factor-I (IGF-I) in the control of pituitary and gonadal functions. The role of growth hormone (GH) and IGF-I is poorly investigated in humans. In animals with altered IGF-I secretion, the gonadotropin and androgen secretions are affected. Similarly, there is evidence that fertility, the onset of puberty and coïtusual maturation are affected in some patients with Laron syndrome and in acr*****ly. In this minireview, we have presented some data obtained in humans and also included results from several experimental models with altered GH/IGF-I secretion, in the hope that the results from animals will possibly help in understanding the important role of IGF-I in the control of neuroendocrine-testicular function in humans.
-3 Spiteri-Grech J, Nieschlag E.
Institute of Reproductive Medicine, The University, Munster, FRG.
Animal experiments and clinical studies on the interactions between growth hormone (GH) and the male hypothalamic-pituitary-gonadal axis have predominantly concentrated on GH and coïtus steroid interactions in the regulation of growth and development, or on the metabolic effects of GH. In contrast, little attention has been paid to the possible effects of GH on spermatogenesis, although the first report dealing with this topic was published almost 30 years ago. The interactions of GH and its main mediator, insulin-like growth factor I (IGF-I), with the hypothalamic-pituitary-gonadal axis, and their role in spermatogenesis have recently been investigated using in vitro systems and different animal models (mice and rats). Using Leydig and Sertoli cell cultures, complex interactions between GH/IGF-I and the gonadotropins affecting differentiated cell functions, e.g. steroidogenesis and cell division, have been demonstrated at the cellular level. In vivo studies using immature and mature hypophysectomized rats and GH-deficient mutant male mice and rats indicate that IGF-I can play an important role in the regulation of steroidogenesis and spermatogenesis. Furthermore, although follicle-stimulating hormone and luteinizing hormone are the major regulators of testicular IGF-I production, GH may play an indirect role by potentiating the actions of the gonadotropins in regulating testicular IGF-I content. A large proportion of men presenting at male-infertility clinics are diagnosed as having idiopathic infertility. Further studies are necessary to investigate whether defects associated with GH and/or IGF-I effects in the testis are the cause of male infertility in a small group of these patients.
PMID: 1295809 [PubMed - indexed for MEDLINE]
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