Objectives: In order to determine the exact pattern of plasma Substance P (SP) concentration during the LH preovulatory surge and the functional correlates which could exist between plasma SP, LH, 17 beta-estradiol (E2) and Progesterone, we performed a detailed analysis of changes in plasma SP concentration, during the critical phases of the LH preovulatory surge in the Human.
Methods: The experimental study was performed in 21 women between the ages of 26 and 35 years. For each subject, blood samples were taken every 15 min, between 07:00 a.m. and 09:00 a.m. for 3 consecutive days when E2 plasma values reached at last 125 pg/ml. Then, each subject, according to the mean LH value of each day, was classified into one of the following groups: 1) the day before the day of the ascending phase, 2) the day of the ascending phase, 3) The day of the LH surge, 4) the day of the descending phase, 5) the day after the day of the descending phase.
Results: Mean SP plasma values for the day of the LH peak, the day of the descending phase and the day after the day of the descending phase were all significantly higher than the values of the day of the ascending phase. Overall, there was an almost linear increase for plasma SP values between the day before the day of the ascending phase and the day after the day of the descending phase Also,this linear increase in plasma SP concentration exhibited a positive correlation (p = 0.016) with plasma progesterone concentrations which also started to increase on the day of the ascending phase of the LH surge.
Conclusions: Taken together with previous results which have shown that the administration of a SP antagonist reduces both the amplitude and the duration of the preovulatory LH surge in the monkey, the increase in plasma SP concentrations, possibly driven by the rise in serum progesterone concentration, which take place at the time of the preovulatory LH surge, is certainly an important element of the Hypothalamo-Pituitary-Gonadal interactive network necessary for the full development of the preovulatory LH surge in the Human.
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Elife
January 2025
Department of Physiology, Development and Neuroscience, Downing site, University of Cambridge, Cambridge, United Kingdom.
The gonadotropin-releasing hormone (GnRH) neurons represent the key output cells of the neural network controlling mammalian fertility. We used GCaMP fiber photometry to record the population activity of the GnRH neuron distal projections in the ventral arcuate nucleus where they merge before entering the median eminence to release GnRH into the portal vasculature. Recordings in freely behaving intact male and female mice revealed abrupt ~8 min duration increases in activity that correlated perfectly with the appearance of a subsequent pulse of luteinizing hormone (LH).
View Article and Find Full Text PDFMetabolism
December 2024
Instituto Maimónides de Investigación Biomédica de Cordoba (IMIBIC), Department of Cell Biology, Physiology and Immunology, University of Cordoba; and Hospital Universitario Reina Sofia, Cordoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain. Electronic address:
Female reproduction is highly sensitive to body energy stores; persistent energy deficit, as seen in anorexia or strenuous exercise, is known to suppress ovulation via ill-defined mechanisms. We report herein that hypothalamic SIRT1, a key component of the epigenetic machinery that links nutritional status and puberty onset via modulation of Kiss1, plays a critical role in the control of the preovulatory surge of gonadotropins, i.e.
View Article and Find Full Text PDFElife
December 2024
Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, United States.
Hypothalamic kisspeptin (Kiss1) neurons are vital for pubertal development and reproduction. Arcuate nucleus Kiss1 (Kiss1) neurons are responsible for the pulsatile release of gonadotropin-releasing hormone (GnRH). In females, the behavior of Kiss1 neurons, expressing Kiss1, neurokinin B (NKB), and dynorphin (Dyn), varies throughout the ovarian cycle.
View Article and Find Full Text PDFAnim Reprod Sci
January 2025
Departamento de Biociencias Veterinarias, Facultad de Veterinaria, Universidad de la República, Ruta 8 km 18, Montevideo 1300, Uruguay.
Am J Reprod Immunol
November 2024
Department of Reproductive Immunology, The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
Problem: There were not only granulosa cells (GCs) but also immune cells in preovulatory follicular fluid. The objective of this study was to explore the interactions between macrophages and GCs via adhesion molecules in preovulatory follicles and the regulatory mechanisms of the interactions.
Method Of Study: Flow cytometry and immunofluorescence were used to detect the expression of ITGB1 in macrophages and fibronectin (FN)1 in GCs in preovulatory follicles from 12 patients.
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