Model simulations of acth pulsatility
| Autor: | Stephanie J. Lent, Brian Goodman, Molly Carnes |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
Adult
Male medicine.medical_specialty Secretory Rate Drinking Pulsatile flow Poisson process Adrenocorticotropic hormone Poisson distribution Models Biological General Biochemistry Genetics and Molecular Biology symbols.namesake Nuclear magnetic resonance Adrenocorticotropic Hormone Pituitary Gland Anterior Stress Physiological Baseline activity Internal medicine medicine Humans Computer Simulation Poisson Distribution General Pharmacology Toxicology and Pharmaceutics Defecation Depression Pulse (signal processing) Chemistry General Medicine Amplitude Endocrinology Pulsatile Flow symbols Female |
| Zdroj: | Life Sciences. 54:1659-1669 |
| ISSN: | 0024-3205 |
| DOI: | 10.1016/0024-3205(94)00606-7 |
| Popis: | Using high intensity venous sampling (1-2 min integrated intervals) we have observed rapid (< 10 min) large amplitude (up to 80 pg/ml) fluctuations in plasma ACTH concentrations in addition to variations at longer time scales. We developed a mathematical model to assess whether plausible physiological explanations could account for our observations and compared model simulations with time series from two human subjects. Three key features enabled the model to accurately simulate the observed time series. 1) The pattern of instantaneous secretory events comprising a pulse followed a Poisson process during baseline activity and rapidly shifted to a step function pattern during a pulsatile episode. 2) The fraction of secreted ACTH shunted between a fast and slow clearance mechanism varied biphasically between baseline and pulsatile states. 3) A brief rate-sensitive suppression of secretion was invoked when secretory rates increased above a threshold amount. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|