FIRST AMENDMENT TO PROMISSORY NOTE

This First Amendment to Promissory Note (“Amendment”) between NNN Gallery
Medical, LLC, a Delaware limited liability company (“Borrower”), and NNN REALTY
ADVISORS, INC., a Delaware corporation (the “Guarantor”) and LASALLE BANK
NATIONAL ASSOCIATION, a national banking association (together with its
successors and assigns, “Lender”) is hereby entered into and effective as of
February 12, 2008.

WHEREAS, Lender made a loan (the “Loan”) to Borrower which is evidenced by that
certain Promissory Note, dated February 5, 2007, in the original principal
amount of SIX MILLION AND 00/100 DOLLARS ($6,000,000.00), made by Borrower to
Lender (the “Note”).

WHEREAS, the Note is secured, in part, by that certain Mortgage, Security
Agreement and Fixture Filing dated as of February 5, 2007 executed by Borrower
in favor of Lender (the “Security Instrument”).

WHEREAS, the parties wish to amend certain provisions of the Note related to
Borrower’s right to defease.

NOW THEREFORE, in consideration of the promises recited above, and for other
good and valuable consideration, the receipt and legal sufficiency of which are
hereby acknowledged, the parties do hereby agree as follows:

1.   The foregoing recitals are hereby incorporated herein as terms of this
Amendment. All defined terms defined or otherwise utilized in the Note or Loan
Documents referred to therein shall have the same meaning in this Amendment,
except to the extent, if any, otherwise defined herein.

2.   The first paragraph in the Subparagraph numbered 3.1 and entitled
“Defeasance.” is hereby amended and restated as follows:  

Notwithstanding any provision of this Paragraph 3 to the contrary (but subject
to the last sentence of this Subparagraph), at any time after the earlier of
(a) March 31, 2010 or (b) two (2) years after the “startup day,” within the
meaning of Section 860G(a)(9) of the Internal Revenue Code of 1986, as amended
from time to time or any successor statute (the “Code”), of a “real estate
mortgage investment conduit” (“REMIC”), within the meaning of Section 860D of
the Code, that holds this Note, and provided no Event of Default has occurred
and is continuing hereunder or under any of the other Loan Documents, Borrower
may cause the release of the Property from the lien of the Security Instrument
and the other Loan Documents upon the satisfaction of the following conditions
(the “Defeasance”):

3.   The Note, as hereby amended, remains in full force and effect. All
references in the Note and any other Loan Document to the Note shall mean the
Note as hereby amended and modified.

4.   This Amendment may be executed in several counterparts, each of which shall
be deemed an original instrument and all of which together shall constitute a
single instrument.

5.   This Amendment shall be governed by and construed in accordance with the
laws of the State of Illinois, without regard to conflicts of law principles.

6.   Guarantor hereby consents to Borrower’s execution of the Amendment and
affirms the existence and the validity of its obligations under (i) the Guaranty
(Securities Laws), dated as of February 5, 2007, (ii) the Guaranty, dated as of
February 5, 2007 and (iii) the Hazardous Substances Indemnification Agreement,
dated February 5, 2007 (collectively, the “Guaranties”) in accordance with its
terms, as the same may be affirmed by this Amendment. Guarantor further agrees
to abide by and be bound by all of the terms of the Guaranties, including but
not limited to, any representations, warranties, covenants, assurances and
indemnifications therein.

[Remainder of page intentionally left blank;
signature page follows.]

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IN WITNESS WHEREOF, the parties have caused this Amendment to be executed as of
the date and year first written above.

 
BORROWER:

      NNN Gallery Medical, LLC, a Delaware limited liability company

By:
  GRUBB & ELLIS HEALTHCARE REIT HOLDINGS, L.P., a Delaware limited
partnership, its sole member
By:
  GRUBB & ELLIS Healthcare REIT, Inc., a Maryland corporation, its
general partner
 
  By: /s/ Shannon K S Johnson
Name: Shannon K S Johnson
Its: Chief Financial Officer

LENDER:

LASALLE BANK NATIONAL ASSOCIATION,
a national banking association

By: /s/ Steven Wasser
Name: Steven Wasser
Title: Managing Director

GUARANTOR:

NNN REALTY ADVISORS, INC.,

a Delaware corporation

By: /s/ Andrea R. Biller
Name: Andrea R. Biller
Its: Executive Vice President

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