LeftoversAltitude and Pulmonary EdemaComments on Anatomy LabCommentsFrog Lab: Control of the HeartRegulation of Heart RateRegulation of Cardiac ContractilityEffect of E/NE on ContractionAmphibians (e.g., Frog)Lab InterventionsMidtermMidterm InformationFrog Lab Slide 1Bioengineering 6000- Systems PhysiologyLeftoversBioengineering/Physiology 6000Frog Lab Slide 2Bioengineering 6000- Systems PhysiologyAltitude and Pulmonary Edema•At sea level, reduced oxygen concentration comes from restricted air flow and capillaries constrict to increase flow in unrestricted airways•At altitude, reduced oxygen concentration is widespread but the resulting capillary constriction is uneven•Result is increase pressure in some alveolae and edema•Edema is patchy but still very dangerousFrog Lab Slide 3Bioengineering 6000- Systems PhysiologyComments on Anatomy LabBioengineering/Physiology 6000Frog Lab Slide 4Bioengineering 6000- Systems PhysiologyComments•Structure;–Intro/overview–Methods–Results and observations–Discussion•Writing–Clear, concise, factual–Careful wording for accuracy–Facts over opinion•Preparation–Figures and captions–Incorporate figures and tables in the text–All measurements in SI systemFrog Lab Slide 5Bioengineering 6000- Systems PhysiologyFrog Lab: Control of the HeartBioengineering/Physiology 6000Frog Lab Slide 6Bioengineering 6000- Systems PhysiologyRegulation of Heart RateSA NodeAChACh: • increases pK• reduces If(muscarinic receptor)Epi,NEEpi/NE; • increases If (1-adrenergic receptor)Frog Lab Slide 7Bioengineering 6000- Systems PhysiologyRegulation of Cardiac Contractility•Increase in amplitude or rate of rise of isometric tension at fixed length,•Free [Ca+2]i is key component•Positive inotropic agents:–epinephrine: stimulate  receptors and increase Ca+2 influx and uptake (load SR)–Caffeine: increases sensitivity of myofilaments and causes release of SR Ca+2•Negative inotropic agents:–ACh: acts mostly on atria to shorten AP and reduce [Ca+2]i –Cadmium: resembles Ca+2 enough to block channel10-710-5100Tension [% max]PeakRestCai [M]0Muscle tensionPassive (rest) tensionTotal tensionTwitch tensionMuscle lengthEffect of NE/EFrog Lab Slide 8Bioengineering 6000- Systems PhysiologyEffect of E/NE on Contraction•constant pretension•reduced shortening (limited by max tension curve)•reduced stroke volume1234tension [g]muscle lengthmaximum isotonic tensionPressureVolumeLeft VentriclestrokevolumeFrog Lab Slide 9Bioengineering 6000- Systems PhysiologyAmphibians (e.g., Frog)•Shared ventricle but blood separated–Spiral fold–Initial flow through pulmonary because of reduced pressure–Resistance to flow varies with breathing (inhale reduces resistance)Frog Lab Slide 10Bioengineering 6000- Systems PhysiologyLab Interventions•Cold Ringer’s solution•ACh•Epinephrine•Isoproterenol •Ca2+-free solution•Caffeine•Cadmium chloride•Potassium chlorideFrog Lab Slide 11Bioengineering 6000- Systems PhysiologyMidtermBioengineering/Physiology 6000Frog Lab Slide 12Bioengineering 6000- Systems PhysiologyMidterm Information•See web site for study topics•Format: –True/false–Short essay–Closed book•Try and start on