Ayumi Yokoyama

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The effect of food deprivation on the pulsatile release of LH was examined in the normal cycling and the ovariectomized (OVX) adult female rat. In the cycling animals, there were significant decreases in the mean plasma LH levels as well as the frequency and amplitude of the LH pulse 48 h after the onset of food deprivation. On the other hand, food(More)
Effects of the suckling stimulus on the daily LH surge induced by chronic oestrogen treatment were examined in ovariectomized lactating rats. Wistar-Imamichi strain rats were kept under 14 h light:10 h darkness (lights on at 05.00 h). Litter size was adjusted to eight on day 1 (day 0 = day of parturition) and ovariectomy performed on day 2. Lactating rats(More)
Numerous endothelial progenitor cell (EPC)-related investigations have been performed in mouse experiments. However, defined characteristics of mouse cultured EPC have not been examined. We focused on fast versus slow adherent cell population in bone marrow mononuclear cells (BMMNCs) in culture and examined their characteristics. After 24 h-culture of(More)
The therapeutic potential of hematopoietic stem cells/endothelial progenitor cells (HSCs/EPCs) for fracture healing has been demonstrated with evidence for enhanced vasculogenesis/angiogenesis and osteogenesis at the site of fracture. The adaptor protein Lnk has recently been identified as an essential inhibitor of stem cell factor (SCF)-cKit signaling(More)
The role of progesterone to increase prolactin (PRL) secretion on the first estrous day in pubertal rats was compared with its role in adult cyclic rats. The first estrus was induced by the administration of pregnant mare serum gonadotrophin (5 IU) at 28 days of age. A subcutaneous administration of 2.5 or 7.5 mg of progesterone/100 g body wt significantly(More)
The location and mechanism of LHRH pulse generator are discussed based on our series of experiments. Suckling stimulus is a novel stimulus that inhibits LH pulses without any cooperation from ovarian steroids, unlike other stimuli such as stress, photoperiod etc. It is directly involved in suppressing the activity of the LHRH pulse generator. The(More)
Abstract The pulsatile luteinizing hormone (LH) secretion in ovariectomized lactating rats bearing complete (CD), anterior (AD), anterolateral (ALD), posterior (PD), or roof (RD) deafferentation of the hypothalamus was determined. All lactating rats were ovariectomized on Day 2 of lactation (Day 0, day of parturition). The deafferentation of nerve fibres to(More)
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