<prompt> Function of thyroid hormones:Inhibits beta myosin heavy chainIncreases cholesterolInhibits ovulationIncreases diastolic blood pressure  <response>: Ans: A Inhibits beta myosin heavy chain Ref: Pal GK, The Thyroid Gland, In: Textbook of Medical Physiology, 2nd ed, Ahuja Publishing House 2011: 46: 352-55Explanation:Physiological Actions of Thyroid HormoneBasal metabolism rate of oxygen consumption Na K ATPase activityThermogenic actionOn nervous systemProliferation of axons, branching of dendritesDevelopment of synapseFormation of neurotransmitter receptorsMyelinationOn growth and developmentPromoting gene expression for GHLinear growth of bone osteoid action, bone remodelingTeeth eruption and developmentOn CVS Heart rate - number of b receptors on SA node; sensitivity of b receptor for catecholamine Myocardial contractilitydeg By inducing expression of myosin heavy chain a MHC activity; suppress b MHC activitydeg Ca ATPase activityBlood pressuredeg HR, stroke volume - systolic BPdeg Thermogenic cutaneous vasodilation - peripheral resistance - diastolic BPOn metabolismCarbohydratedeg glucose absorptiondeg hepatic gluconeogenesisdeg glycogenolysisFatdeg lipolysis, stimulate cholesterol synthesis - also oxidation and bile excretion - net reduction in plasma cholesterol, total lipidProteindeg Proteolysis and turnoverSvnergize net effect of catecholaminesOn respiratory system oxygen utilizationStimulate erythropoiesisOn GITEnhance the motility appetite, food intakeSkeletal muscle expression of MHC genesOn reproductive systemFemale - follicular maturation, ovulationMale - spermatogenesisOn kidney renal blood flow, GFR 