Exam 2 Study Guide Hormones Prohormones- inactive hormones that must be cut and sliced together to be active Synergistic- 2 or more hormones work together
... [Show More] to produce an effect (additive/complementa ry) Producing milk requires estrogen, prolactin, and oxytocin Permissive- 1 hormone makes the target cell more responsive to a second hormone Exposure to estrogen makes the uterus more responsive to progesterone (increase sensitivity) Antagonistic- hormones work in opposite directions Insulin and glucagon in adipose tissue: insulin= fat storage, glucagon= fat breakdown Understand the hypothalamic-pituitary axis, including negative feedback inhibition. Hypothalamus: Releasing hormones (CRH, TRH, GnRH) o CRH- stimulates secretion of adrenocorticotropic hormone (ACTH) o TRH- [thyroid] stimulates secretion of (TSH) o GnRH- stimulates secretion of follicle- stimulating hormone(FSH) and luteinizing hormone(LH) Pituitary: Trophic hormones o Tropic hormone- hormones stimulate hormone secretion in other glands o Anterior: true endocrine gland – signaled via vasculature 6 hormones FSH- promotes gamete production and stimulates estrogen production in females o Stimulated by GnRH; inhibited by sex steroids and inhibin LH- stimulates sex hormone secretion; ovulation and corpus luteum formation in females; stimulates testosterone secretion in males o Stimulated by GnRH; inhibited by sex steroids GH- promotes protein synthesis and growth; lipolysis and increased blood glucose o Inhibited by somatostatin; stimulated by growth-hormone releasing hormone ACTH- stimulates secretion of glucocorticoids o Stimulated by CRH; inhibited by glucocorticoids TSH- stimulates secretions of thyroid hormones o Stimulated by TRH; inhibited by thyroid hormones Prolactin (PRL)- promotes milk production in lactating females; additional actions in organs o Inhibited by PIH Anterior pituitary regulated by secreting hormones 2 parts: Pars distalis and pars tuberalis o Posterior: neuronal tissue 2 hormones ADH- promotes the retention of water in the kidneys (vasopressin) Oxytocin- stimulates contractions in childbirth and milk in lactation o Also called the pars nervosa Know the hormones released from each gland, and the effects mediated by each hormone: Thyroid- below the larynx, 2 lobes connected by isthmus o T3 (active) &T4 (converted to T3 by iodinases) Must have iodine to made thyroid hormone o Thyroglobulin (inner) & Calcitonin (outer) Parathyroid – 4 glands embedded in back of thyroid o PTH- promotes a rise in blood calcium by acting on bones, kidneys, and intestine Adrenal – found atop the kidneys o Medulla (inner) Epinephrine & Norepinephrine- response to sympathetic neural stimulation o Cortex (outer): Steroid hormones- secrete in response to ACTH Secretes hormones from cholesterol; corticosteroids or corticoids Mineralocorticoids- regulate Na and K balance (glomerulosa) Glucocorticoids- regulate glucose metabolism (fasciculata) Adrenal Androgens- weak sex hormones that supplement whose made in the gonads (reticularis) Cortisol- Stimulates protein degradation, glucogenesis (raises blood glucose, and lipolysis [Show Less]