<Tr> <Th> Part of </Th> <Td> Middle layer of wall of blood vessels </Td> </Tr> <Tr> <Th_colspan="2"> Identifiers </Th> </Tr> <Tr> <Th> Latin </Th> <Td> tunica media vasorum </Td> </Tr> <Tr> <Th> MeSH </Th> <Td> D017540 </Td> </Tr>

What is the function of the smooth muscle in the tunica media