Diapositiva 1

Apuntes

[Diapositiva 1] Endocrine System Anatomy and Physiology II 16 Professor Hoffmann [Diapositiva 2] Mechanisms of Intercellular Communication (1 of 2) Mechanism Transmission Chemical Signals Distribution of Effects Direct communication Two cells are touching. One cell communicates to another. Through gap junctions Ions, small solutes, lipid-soluble materials Usually limited to adjacent cells of the same type that are interconnected by connexons Paracrine communication One cell communicates with 3 small cells beside it. Through extracellular fluid Paracrines Primarily limited to the local area, where paracrine concentrations are relatively high; target cells must have appropriate receptors (see Modules 3.3, 11.8) Autocrine communication A chemical comes out of the center of a cell, then back to cell’s sides. Through extracellular fluid Autocrines Limited to the cell that secretes the chemical signal [Diapositiva 3] Mechanisms of Intercellular Communication (2 of 2) Mechanism Transmission Chemical Signals Distribution of Effects Endocrine communication Three cells communicate with a blood vessel below. Through the bloodstream Hormones Target cells are mainly in other distant tissues...