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Integrated Cardiovascular Responses
Published in Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal, Principles of Physiology for the Anaesthetist, 2020
Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal
The endocrine response to shock also stimulates the pituitary gland. Adrenocorticotrophic hormone (ACTH) is released from the anterior pituitary, stimulating the adrenal cortex to increase the synthesis of glucocorticoids and aldosterone. High circulating glucocorticoid levels increase the responsiveness of vascular smooth muscles to catecholamines. Growth hormone released from the anterior pituitary increases blood glucose and free fatty acid levels. Dynorphins and endorphins are also released from the anterior pituitary. ADH released from the posterior pituitary acts principally on the renal collecting ducts to conserve water. It is also a vasoconstrictor.
Anatomy and physiology
Published in Suzanne Everett, Handbook of Contraception and Sexual Health, 2020
Three hormones are the principal regulators of the male reproductive system: hypothalamic hormone, anterior pituitary hormones and testicular hormones. Anterior pituitary hormones control spermatogenesis and androgen production, and these are called follicle-stimulating hormone or luteinizing hormone.
Summation of Basic Endocrine Data
Published in George H. Gass, Harold M. Kaplan, Handbook of Endocrinology, 2020
Estrogens are synthesized in the ovaries, placenta, and adrenal cortex. In the male, synthesis is in the testes, liver, and other tissues. The ovary in the nongravid female is the primary source. Its follicles in the first half of the ovarian cycle secrete estrogens by its granulosa cells. The estrogens include β-estradiol, estrone, and estriol. Estradiol is the most important for development of the female phenotype. At ovulation, the second half of the cycle begins and the empty follicle becomes a new endocrine producer called the corpus luteum; this secretes progesterone and some β-estradiol. The growth of the follicles as well as its estrogen secretions are stimulated by FSH from the anterior pituitary. Toward the close of the follicular phase, two to three days before ovulation occurs, LH is stimulated to secretion by way of positive feedback on the hypothalamus but mainly on the anterior pituitary. Between ovulation and menstruation, the hormones exert a negative effect on the hypothalamus and pituitary and this suppresses FSH and LH; these will increase again beginning with menstruation.
Measuring stress: a review of the current cortisol and dehydroepiandrosterone (DHEA) measurement techniques and considerations for the future of mental health monitoring
Published in Stress, 2023
Tashfia Ahmed, Meha Qassem, Panicos A. Kyriacou
HPA activity leads to the release of neurohormones, such as CRH into general circulation (Schmidt et al., 2011). This triggers a hormonal cascade in which ACTH is released, which induces glucocorticoid synthesis and secretion of glucocorticoids into circulation. The central nervous system (CNS) and the endocrine system are tightly interconnected to coordinate glucocorticoid activity (Stephens et al., 2014). After a stressful event activates the HPA axis, the increase of cortisol and other glucocorticoids facilitate the body’s recovery from the stressor (Gjerstad et al., 2018). Cortisol regulates its secretion through a negative feedback mechanism involving the activation of the glucocorticoid receptor in the anterior pituitary gland. This mechanism is necessary to eliminate the HPA axis response to stress, i.e. to aid the body’s recovery from the stressor, as well as the maintenance of optimal levels of cortisol secretion in basal conditions (Gjerstad et al., 2018).
The pharmacotherapeutic options in patients with catecholamine-resistant vasodilatory shock
Published in Expert Review of Clinical Pharmacology, 2022
Timothy E. Albertson, James A. Chenoweth, Justin C. Lewis, Janelle V. Pugashetti, Christian E. Sandrock, Brian M. Morrissey
The endogenous hormone vasopressin circulates in the blood after it is released from the posterior pituitary gland. VP mainly ensures osmoregulation by its effect on the arginine vasopressin receptor 2 (AVPR2) located primarily in the distal convoluted tubules promoting water retention. The antidiuretic hormone effect is normally the major effect of VP, but in shock conditions, even higher circulatory levels of VP are naturally released. These higher levels also stimulate arginine vasopressin receptor 1a (AVPR1a) generating powerful vasoconstriction. Potentially when VP is given exogenously, it maintains better kidney perfusion than exogenous NE because there are more AVPR1a receptors in the glomerular efferent than afferent arterioles [21]. In addition, the stimulation of arginine vasopressin receptor 1b (AVPR1b) by VP generates the release of adrenocorticotropic hormone (ACTH) from the anterior pituitary resulting in release of cortisol from the adrenal gland. The higher levels of ACTH generated by VP release generate increased natural levels of endogenous cortical steroids in shock patients.
Association between dopamine transporter gene (DAT1/SLC6A3) variants and infertility in the Turkish females
Published in Gynecological Endocrinology, 2022
Orcun Avsar, Nesibe Derinoz, Filiz Yilmaz, Musa Yilmaz, Umit Gorkem
Prolactin (PRL) which is primarily produced and secreted by the anterior pituitary gland is a peptide hormone and modulates various biological processes such as lactogenesis, immune response, reproductive behavior, angiogenesis, and osmoregulation [7]. Hyperprolactinemia (high amount of circulating PRL) impairs ovulation and may be one of the causes of infertility in females and males. The females with higher amount of prolactin during menstrual cycle have worse chance to conceive [8]. Tuberoinfundibular dopaminergic pathway regulates prolactin secretion negatively [9]. In this regard, disturbances in dopamine neurotransmission can lead to abnormal prolactin gene expression and secretion. Dopamine transporter (DAT) that is one of the key players of dopamine neurotransmission reuptakes dopamine from synaptic cleft into presynaptic dopaminergic neuron and terminates neurotransmission. Mutations in SLC6A3 gene that encodes dopamine transporter protein may be associated with various diseases [10].