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The hypothalamic insulin-like growth factor-1 receptor and its relationship to gonadotropin-releasing hormones neurones during postnatal development


, : The hypothalamic insulin-like growth factor-1 receptor and its relationship to gonadotropin-releasing hormones neurones during postnatal development. Journal of Neuroendocrinology 16(2): 160-169

Reproduction in vertebrates is controlled by hypophysiotropic gonadotropin-releasing hormone (GnRH) neurones. Pulsatile GnRH release increases during reproductive development, resulting in the onset and progression of puberty and, ultimately, the acquisition and maintenance of adult reproductive function. These changes in GnRH release are largely due to inputs to GnRH cells from other factors, including the neurotrophic factor, insulin-like growth factor-1 (IGF-1). Here, molecular studies were undertaken to quantify expression of IGF-1 receptor (IGF-1R) mRNA in the preoptic area-anterior hypothalamus (POA-AH) and mediobasal hypothalamus (MBH)-median eminence (ME), the sites of GnRH perikarya and neuroterminals, respectively. Immunocytochemical studies were also carried out to study the anatomical relationship between the IGF-1R and GnRH neurones. Experiments were performed in a developmental context using neonatal (P5), peripubertal ( approximately P30) and adult (P60) male and female mice. We found that IGF-1R mRNA levels in the POA-AH were significantly different among all age groups, with levels higher at P60 then P5 or approximately P30. Levels of IGF-1R mRNA in the MBH-ME were lower at P5 than approximately P30 or P60. Qualitative observations suggested that IGF-1R immunoreactivity in POA-AH increased from P5 through P60. Quantitative double-label immunocytochemistry studies showed that GnRH perikarya expressed IGF-1R. Taken together, the results demonstrate expression of, and developmental changes in, IGF-1R gene and protein in brain regions containing GnRH and other neuroendocrine cells. Moreover, the novel finding that the IGF-1R is expressed on GnRH perikarya in vivo suggests a potential direct anatomical locus where IGF-1 can regulate reproductive development and function.

US$19.90

PMID: 14764003

DOI: 10.1111/j.0953-8194.2004.01149.x


Other references

Mar, K.E.; Sen, P.; Tan, K.; Krishnan, R.; Ratkalkar, K., 1993: Bronchiolitis obliterans organizing pneumonia associated with massive L-tryptophan ingestion. A 51-year-old woman developed acute febrile illness with respiratory failure following intake of L-tryptophan. An open lung biopsy specimen established the histopathologic nature of the lung lesion as bronchiolitis obliterans organizing pneumonia...

Wagner W.; Wiemken A.; Matile P., 1986: Regulation of fructan metabolism in leaves of barley hordeum vulgare cultivar gerbel. Excised primary leaf blades of barley (Hordeum vulgare L. cv Gerbel) rapidly synthesized large quantities of fructan in the light and, upon transfer to the dark, they rapidly degraded it again. In the course of such a light/dark cycle the activiti...

Warren David H., 1981: Seismic-refraction measurements of crustal structure near Santa Rosa and Ukiah, California. U S

Anonymous, 1990: Occupational HIV exposure: a national update. The Federal Centre for AIDS. Dimensions in Health Service 67(8): 26-28

Jefferies, R., L.; Drent, R., H., 2006: Arctic geese, migratory connectivity and agricultural change: calling the sorcerer's apprentice to order. The current favourable numerical status of most arctic-breeding goose populations conceals an increasing dependence on man-modified habitats for much of the year. Almost all populations are now heavily dependent on agricultural crops when the bir...

Alves, G.; Macrini, C.Menezes.Trindade.; de Souza Nascimento, Pícia.; Morais, Jé.Carlos.; Ornellas, A.Augusto., 2005: Detection and expression of Epstein-Barr Virus (EBV) DNA in tissues from penile tumors in Brazil. Cancer Letters 227(2): 225-225

Prebensen, N.K.; Kleiven, J., 2005: Stability in outbound travel motivation: a Norwegian example. Only travel and leisure motives with some degree of stability are likely to contribute to predictions of travel choice or behaviour. Eight motive scales, based on previous research and consultations with a travel company, were used in a survey of...

Stage, G., 1971: Boiled wort colour and its power as an indicator. Brauwelt 111 (48) 1007-1012

Zheng, L.; Paik, W.Y.; Cesnjaj, M.; Balla, T.; Tomić, M.; Catt, K.J.; Stojilkovic, S.S., 1995: Effects of the phospholipase-C inhibitor, U73122, on signaling and secretion in pituitary gonadotrophs. The effects of inhibition of phosphoinositide hydrolysis by U73122 [1-(6-[17 beta-3-methoxyestra-1,3,5- (10) triene-17-yl] amino/hexyl) 1H-pyrroledione] and neomycin on agonist-stimulated intracellular signaling and secretory responses were analyz...

Sessarego, M.; Fugazza, G.; Bruzzone, R.; Patrone, F., 1994: Variant Philadelphia chromosome translocations are frequently associated with additional structural abnormalities. This work contains a cytogenetic analysis of 507 consecutive CML patients examined at diagnosis before any therapeutic treatment. Philadelphia chromosome translocations different from the standard t(9;22)(q34;q11) were observed in 28 patients (5.5...