Millipore Sigma Vibrant Logo
 

rptmag-86k


26 Results Advanced Search  
Showing

Narrow Your Results Use the filters below to refine your search

Document Type

  • (12)
  • (4)
  • (3)
  • (2)
  • (1)
  • Show More
Can't Find What You're Looking For?
Contact Customer Service

 
  • Protocol- RPTMAG-86K

    Document Type:
    Protocols
    Product Catalog Number:
    RPTMAG-86K
    Product Catalog Name:
    MILLIPLEX MAP Rat Pituitary Magnetic Bead Panel - Endocrine Multiplex Assay
  • Dynamic changes in fetal Leydig cell populations influence adult Leydig cell populations in mice. 23568777

    Testes contain two distinct Leydig cell populations during development: fetal and adult Leydig cells (FLCs and ALCs, respectively). ALCs are not derived from FLCs, and it is unknown whether these two populations share common progenitors. We discovered that hedgehog (Hh) signaling is responsible for transforming steroidogenic factor 1-positive (SF1(+)) progenitors into FLCs. However, not all SF1(+) progenitors become FLCs, and some remain undifferentiated through fetal development. We therefore hypothesized that if FLCs and ALCs share SF1(+) progenitors, increased Hh pathway activation in SF1(+) progenitor cells could change the dynamics and distribution of SF1(+) progenitors, FLCs, and ALCs. Using a genetic model involving constitutive activation of Hh pathway in SF1(+) cells, we observed reduced numbers of SF1(+) progenitor cells and increased FLCs. Conversely, increased Hh activation led to decreased ALC populations prepubertally, while adult ALC numbers were comparable to control testes. Hence, reduction in SF1(+) progenitors temporarily affects ALC numbers, suggesting that SF1(+) progenitors in fetal testes are a potential source of both FLCs and ALCs. Besides transient ALC defects, adult animals with Hh activation in SF1(+) progenitors had reduced testicular weight, oligospermia, and decreased sperm mobility. These defects highlight the importance of properly regulated Hh signaling in Leydig cell development and testicular functions.
    Document Type:
    Reference
    Product Catalog Number:
    RPTMAG-86K
    Product Catalog Name:
    MILLIPLEX MAP Rat Pituitary Magnetic Bead Panel - Endocrine Multiplex Assay
  • Global but not gonadotrope-specific disruption of Bmal1 abolishes the luteinizing hormone surge without affecting ovulation. 23736292

    Although there is evidence for a circadian regulation of the preovulatory LH surge, the contributions of individual tissue clocks to this process remain unclear. We studied female mice deficient in the Bmal1 gene (Bmal1(-/-)), which is essential for circadian clock function, and found that they lack the proestrous LH surge. However, spontaneous ovulation on the day of estrus was unaffected in these animals. Bmal1(-/-) females were also deficient in the proestrous FSH surge, which, like the LH surge, is GnRH-dependent. In the absence of circadian or external timing cues, Bmal1(-/-) females continued to cycle in constant darkness albeit with increased cycle length and time spent in estrus. Because pituitary gonadotropes are the source of circulating LH and FSH, we assessed hypophyseal circadian clock function and found that female pituitaries rhythmically express clock components throughout all cycle stages. To determine the role of the gonadotrope clock in the preovulatory LH and FSH surge process, we generated mice that specifically lack BMAL1 in gonadotropes (GBmal1KO). GBmal1KO females exhibited a modest elevation in both proestrous and baseline LH levels across all estrous stages. BMAL1 elimination from gonadotropes also led to increased variability in estrous cycle length, yet GBmal1KO animals were otherwise reproductively normal. Together our data suggest that the intrinsic clock in gonadotropes is dispensable for LH surge regulation but contributes to estrous cycle robustness. Thus, clocks in the suprachiasmatic nucleus or elsewhere must be involved in the generation of the LH surge, which, surprisingly, is not required for spontaneous ovulation.
    Document Type:
    Reference
    Product Catalog Number:
    RPTMAG-86K
    Product Catalog Name:
    MILLIPLEX MAP Rat Pituitary Magnetic Bead Panel - Endocrine Multiplex Assay