You are here:
Effects of Environmental Toxicants on the Neuroendocrine Control of Female Reproduction
Citation:
Farmer, W. AND T. Stoker. Effects of Environmental Toxicants on the Neuroendocrine Control of Female Reproduction. Chapter 4, Charlene McQueen (ed.), Comprehensive Toxicology, 3rd Edition. ELSEVIER, AMSTERDAM, Holland, , 303-321, (2018).
Impact/Purpose:
The central nervous system (CNS) and pituitary play a key regulatory role in reprod uctive function in the female. The hypothalamus integrates sensory and ovarian steroid hormone input to modulate the activity of neurons that synthesize and release gonadotropin-releasing hormone (GnRH), which in turn governs the secretion of luteinizing hormone (LH) (Svalheim et al 2003) and follicle-stimulating hormone (FSH) from the pituitary. A growing body of evidence indicates that environmental toxicants can alter female reproductive function by disrupting the complex hypothalamic neuronal control of the pituitary and subsequently the endocrine control of ovarian function and female reproduction. These effects may be mediated by a direct action of the chemical on the GnRH neurons or indirectly by impairing the release or activity of neurotransmitters or neuropeptides of neurons that regulate GnRH secretion. Although most studies in this area have used rodent models, non human primate and human reproductive systems do share a number of common characteristics with the mouse and rat. All are spontaneous ovulators and all have a mid-cycle gonadotropin surge that triggers follicular development and maturational changes of the oocytc within the ovary as well as ovulation.
Description:
The hypothalamus and pituitary are known to play key roles in reproductive function. A growing body of evidence indicates that environmental toxicants can alter female reproductive function by disrupting hypothalamic control of the pituitary and subsequently, the endocrine control of ovarian function. This chapter will review the current literature on the effects of environmental toxicants on hypothalamic regulation of pituitary hormone secretion. The impact of toxicant exposures during critical periods of the estrous cycle as well as the concept of acquired tolerance following chronic exposure to specific toxicants will also be discussed. We will also briefly mention several other reproductive processes that might be disrupted by environmental toxicants, which target the hypothalamic regulation of pituitary hormone secretion in the female.
