[ @objname = ] 'object_name'

Is the current qualified or nonqualified name of the user object or data type. If the object to be renamed is a column in a table, object_name must be in the form table.column or schema.table.column. If the object to be renamed is an index, object_name must be in the form table.index or schema.table.index.

Quotation marks are only necessary if a qualified object is specified. If a fully qualified name, including a database name, is provided, the database name must be the name of the current database. object_name is nvarchar(776), with no default.

[ @newname = ] 'new_name'

Is the new name for the specified object. new_name must be a one-part name and must follow the rules for identifiers. newname is sysname, with no default.

Note
Trigger names cannot start with # or ##.

[ @objtype = ] 'object_type'

Is the type of object being renamed. object_type is varchar(13), with a default of NULL, and can be one of these values.

Value	Description
COLUMN	A column to be renamed.
DATABASE	A user-defined database. This object type is required when renaming a database.
INDEX	A user-defined index.
OBJECT	An item of a type tracked in sys.objects. For example, OBJECT could be used to rename objects including constraints (CHECK, FOREIGN KEY, PRIMARY/UNIQUE KEY), user tables, and rules.
USERDATATYPE	An alias data type or CLR User-defined Types added by executing CREATE TYPE or sp_addtype.

0 (success) or a nonzero number (failure)

You can change the name of an object or data type in the current database only. The names of most system data types and system objects cannot be changed.

sp_rename automatically renames the associated index whenever a PRIMARY KEY or UNIQUE constraint is renamed. If a renamed index is tied to a PRIMARY KEY constraint, the PRIMARY KEY constraint is also automatically renamed by sp_rename.

sp_rename can be used to rename primary and secondary XML indexes.

Renaming a stored procedure, function, view, or trigger will not change the name of the corresponding object name in the definition column of the sys.sql_modules catalog view. Therefore, we recommend that sp_rename not be used to rename these object types. Instead, drop and re-create the object with its new name.

Renaming an object such as a table or column will not automatically rename references to that object. You must modify any objects that reference the renamed object manually. For example, if you rename a table column and that column is referenced in a trigger, you must modify the trigger to reflect the new column name. Use sys.sql_expression_dependencies to list dependencies on the object before renaming it.

To rename objects, columns, and indexes, requires ALTER permission on the object. To rename user types, requires CONTROL permission on the type. To rename a database, requires membership in the sysadmin or dbcreator fixed server roles

A. Renaming a table

USE AdventureWorks2008R2;
GO
EXEC sp_rename 'Sales.SalesTerritory', 'SalesTerr';
GO

B. Renaming a column

USE AdventureWorks2008R2;
GO
EXEC sp_rename 'Sales.SalesTerritory.TerritoryID', 'TerrID', 'COLUMN';
GO

C. Renaming an index

USE AdventureWorks2008R2;
GO
EXEC sp_rename N'Purchasing.ProductVendor.IX_ProductVendor_VendorID', N'IX_VendorID', N'INDEX';
GO

D. Renaming an alias data type

USE AdventureWorks2008R2;
GO
EXEC sp_rename N'Phone', N'Telephone', N'USERDATATYPE';
GO

Sumber : 
http://msdn.microsoft.com/en-us/library/ms188351.aspx