Stochastic modeling of the hypothalamic pulse generator activity.

Luteinizing hormone (LH) is released by the pituitary in discrete pulses. In the monkey, the appearance of LH pulses in the plasma is invariably associated with sharp increases (i.e, volleys) in the frequency of the hypothalamic pulse generator electrical activity, so that continuous monitoring of this activity by telemetry provides a unique means to study the temporal structure of the mechanism generating the pulses. To assess whether the times of occurrence and durations of previous volleys exert significant influence on the timing of the next volley, we used a class of periodic counting process models that specify the stochastic intensity of the process as the product of two factors: 1) a periodic baseline intensity and 2) a stochastic regression function with covariates representing the influence of the past. This approach allows the characterization of circadian modulation and memory range of the process underlying hypothalamic pulse generator activity, as illustrated by fitting the model to experimental data from two ovariectomized rhesus monkeys.

[1]  William M. Bolstad.  The multiprocess dynamic linear model with biased perturbations: A real time model for growth hormone level , 1988 .

[2]  J. Thalabard,et al.  Effects of naloxone on estrogen-induced changes in hypothalamic gonadotropin-releasing hormone pulse generator activity in the rhesus monkey. , 1993, Neuroendocrinology.

[3]  J. Thalabard,et al.  Identification of pulses in hormone time series using outlier detection methods. , 1992, Statistics in medicine.

[4]  J. Thalabard,et al.  Duration of phasic electrical activity of the hypothalamic gonadotropin-releasing hormone pulse generator and dynamics of luteinizing hormone pulses in the rhesus monkey. , 1990, Proceedings of the National Academy of Sciences of the United States of America.

[5]  Peter J. Diggle,et al.  A Non-Gaussian Model for Time Series with Pulses , 1989 .

[6]  F. Komaki.  State-space modelling of time series sampled from continuous processes with pulses , 1993 .

[7]  F. O'Sullivan,et al.  Deconvolution of episodic hormone data: an analysis of the role of season on the onset of puberty in cows. , 1988, Biometrics.

[8]  Odile Pons,et al.  Cox's Periodic Regression Model , 1988 .

[9]  M D Chen,et al.  Radiotelemetric monitoring of hypothalamic gonadotropin-releasing hormone pulse generator activity throughout the menstrual cycle of the rhesus monkey. , 1991, Endocrinology.

[10]  J. Kaufman,et al.  Electrophysiological manifestation of luteinizing hormone-releasing hormone pulse generator activity in the rhesus monkey: influence of alpha-adrenergic and dopaminergic blocking agents. , 1985, Endocrinology.

[11]  E. Knobil,et al.  The neuroendocrine control of the menstrual cycle. , 1980, Recent progress in hormone research.

[12]  J. Kaufman,et al.  Central electrophysiologic correlates of pulsatile luteinizing hormone secretion in the rhesus monkey. , 1984, Neuroendocrinology.