<Li> (extracellular) ADP </Li> <Tr> <Td> L - arginine </Td> <Td> imidazoline and α - 2 receptor? </Td> <Td> G → ↓ cAMP → activation of Na / K - ATPase → ↓ intracellular Na → ↑ Na / Ca exchanger activity → ↓ intracellular Ca </Td> </Tr> <Tr> <Td> bradykinin </Td> <Td> bradykinin receptor </Td> <Td> </Td> </Tr> <Tr> <Td> substance P </Td> <Td> </Td> <Td> </Td> </Tr>

What is the term that means lack of blood vessels