Meaning of macros in zabbix 2.2 macros?

Question

Macros

Please advise. Is it possible to use in zabbix a macro value consisting of another macro?
for example i have:
{$SOME_ROOT_OID} = .1.3.6.1.4.1
{$MY_TABLE_OID} = {$SOME_ROOT_OID}.1024.145
how will the {$MY_TABLE_OID} value in the item's SNMP OID field expand?
I would like {$MY_TABLE_OID} -> .1.3.6.1.4.1.1024.145
But what about in reality? And how to check? (zabbix 2.2.8)