Jessica Wang BIOEN 498 E – Quantitative Physiology and Transport (Winter 2015) Cells in the Myocardium Type of cell Description Function Cardiomyocyte Heart muscle cell in the cell. Makes the pulsing motions of the Striated. Contains myofibrils that heart muscle connect together sarcomeres. Synthetic nerve ending Nerve cells – receive signals Parasympathetic nerve ending Nerve cells – receive signals Fibroblasts Branched cytoplasm with an elliptical shaped nucleus that may have two or more nucleolus. Thin cells, squamous cells. No space in between the cells Endothelial Cells Pericytes Red blood cells (erythrocytes in blood) Macrophages (in blood) Smooth muscle cells Purkinje fibers Lay on the basement membrane. Communicate with endothelial cells via signals. Cells full of hemoglobin. Sort of bowl shaped. No nucleus or mitochondria. Large white blood cells. Flexible cell membranes Contractile muscle cells that respond to nerve endings Located on inner ventricular walls of heart. Very branched, thin cells. Helps to increase the heart rate to sympathetic stimuli. Activated by epinephrine, norepinephrine. Helps to decrease heart rate in response to parasympathetic stimuli. Makes EC matrix and collagen Make a barrier and line the inside of blood vessels and lymphatic vessels. Wrap around the endothelial cells and contract or release vessels. To carry around oxygen all around the body. To engulf pathogens/debris and destroy them Constrict or dilate vessels according to autonomic NS. Transmit electrical signals for heart beat. Transport Processes Action potential ions moved via voltage gated channels. Muscle contraction when sarcomeres shorten. Synaptic cleft has vesicles of neurotransmitter and sometimes reuptake pumps ^^ Cells can travel around on top of endothelial cells to get to sites where it is needed Not designed to move? When endothelial cells are being shed they detach and flow away? Signals have to transmit somehow? Paracrine signaling. Their job is to transport oxygen all throughout the body. Iron conjugate Phagocytosis—process of engulfing. Signaling for inflammatory response. Contracts by action potentials, have vesicles of ions/signal Electrical conduction has to be FAST. Have lots of voltage gated channels to transmit AP.