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                                                                     EXHIBIT 3.1

                              ARTICLES OF AMENDMENT
                                       TO
                 AMENDED AND RESTATED ARTICLES OF INCORPORATION
                                       OF
                            DIAMETRICS MEDICAL, INC.

     1. The name of the corporation is Diametrics Medical, Inc.

     2. The following is the full and complete text of the first paragraph of
Article 3 of the Amended and Restated Articles of Incorporation of Diametrics
Medical, Inc., as amended:

          "The total number of shares of capital stock which the corporation is
     authorized to issue shall be 65,000,000 shares, consisting of 60,000,000
     shares of common stock, par value $.01 per share ("Common Stock"), and
     5,000,000 shares of preferred stock, par value $.01 per share ("Preferred
     Stock")."

     3. The foregoing amendment has been adopted pursuant to Chapter 302A of the
Minnesota Business Corporation Act.

     IN WITNESS WHEREOF, the undersigned, the Secretary of Diametrics Medical,
Inc., being duly authorized on behalf of Diametrics Medical, Inc., has executed
this document on this 22nd of May, 2003.


                                                          /s/ Kenneth L. Cutler
                                                          ----------------------
                                                          Secretary

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                 AMENDED AND RESTATED ARTICLES OF INCORPORATION
                                       OF
                            DIAMETRICS MEDICAL, INC.
                            (as amended May 22, 2003)

                                ARTICLE 1. NAME

The name of the corporation is Diametrics Medical, Inc.

                          ARTICLE 2. REGISTERED OFFICE

The address of the registered office of the corporation is 2658 Patton Road,
Roseville, Minnesota 55113.

                          ARTICLE 3. AUTHORIZED SHARES

1.   Authorized Shares.

The total number of shares of capital stock which the corporation is authorized
to issue shall be 65,000,000 shares, consisting of 60,000,000 shares of common
stock, par value $.01 per share ("Common Stock"), and 5,000,000 shares of
preferred stock, par value $.01 per share ("Preferred Stock").

2.   Common Stock.

All shares of Common stock shall be voting shares and shall be entitled to one
vote per share. Holders of Common Stock shall not be entitled to cumulate their
votes in the election of directors and shall not be entitled to any preemptive
rights to acquire shares of any class or series of capital stock of the
corporation. Subject to any preferential rights of holders of Preferred Stock,
holders of Common Stock shall be entitled to receive their pro rata share, based
upon the number of shares of Common Stock held by them, of such dividends or
other distributions as may be declared by the board of directors from time to
time and of any distribution of the assets of the corporation upon its
liquidation, dissolution or winding up, whether voluntary or involuntary.

3.   Preferred Stock.

The board of directors of the corporation is hereby authorized to provide, by
resolution or resolutions adopted by such board, for the issuance of Preferred
Stock from time to time in one or more classes and/or series, to establish the
designation and number of shares of each such class or series, and to fix the
relative rights and preferences of the shares of each such class or series, all
to the full extent permitted by the Minnesota Business Corporation Act, Section
302A.401, or any successor provision. Without limiting the generality of the
foregoing, the board of directors is authorized to provide that shares of a
class or series of Preferred Stock:

     (a) are entitled to cumulative, partially cumulative or noncumulative
     dividends or other distributions payable in cash, capital stock or
     indebtedness of the corporation or other property, at such times and in
     such amounts as are set forth in the board resolutions establishing such
     class or series or as are determined in a manner specified in such
     resolutions;

     (b) are entitled to a preference with respect to payment of dividends over
     one or more other classes and/or series of capital stock of the
     corporation;

     (c) are entitled to a preference with respect to any distribution of assets
     of the corporation upon its liquidation, dissolution or winding up over one
     or more other classes and/or series of capital

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     stock of the corporation in such amount as is set forth in the board
     resolutions establishing such class or series or as is determined in a
     manner specified in such resolutions;

     (d) are redeemable or exchangeable at the option of the corporation and/or
     on a mandatory basis for cash, capital stock or indebtedness of the
     corporation or other property, at such times or upon the occurrence of such
     events, and at such prices, as are set forth in the board resolutions
     establishing such class or series or as are determined in a manner
     specified in such resolutions;

     (e) are entitled to the benefits of such sinking fund, if any, as is
     required to be established by the corporation for the redemption and/or
     purchase of such shares by the board resolutions establishing such class or
     series;

     (f) are convertible at the option of the holders thereof into shares of any
     other class or series of capital stock of the corporation, at such times or
     upon the occurrence of such events, and upon such terms, as are set forth
     in the board resolutions establishing such class or series or as are
     determined in a manner specified in such resolutions;

     (g) are exchangeable at the option of the holders thereof for cash, capital
     stock or indebtedness of the corporation or other property, at such times
     or upon the occurrence of such events, and at such prices, as are set forth
     in the board resolutions establishing such class or series or as are
     determined in a manner specified in such resolutions;

     (h) are entitled to such voting rights, if any, as are specified in the
     board resolutions establishing such class or series (including, without
     limiting the generality of the foregoing, the right to elect one or more
     directors voting alone as a single class or series or together with one or
     more other classes and/or series of Preferred Stock, if so specified by
     such board resolutions) at all times or upon the occurrence of specified
     events; and

     (i) are subject to restrictions on the issuance of additional shares of
     Preferred Stock of such class or series or of any other class or series, or
     on the reissuance of shares of Preferred Stock of such class or series or
     of any other class or series, or on increases or decreases in the number of
     authorized shares of Preferred Stock of such class or series or of any
     other class or series.

Without limiting the generality of the foregoing authorizations, any of the
rights and preferences of a class or series of Preferred Stock may be made
dependent upon facts ascertainable outside the board resolutions establishing
such class or series, and may incorporate by reference some or all of the terms
of any agreements, contracts or other arrangements entered into by the
corporation in connection with the issuance of such class or series, all to the
full extent permitted by the Minnesota Business Corporation Act. Unless
otherwise specified in the board resolutions establishing a class or series of
Preferred Stock, holders of a class or series of Preferred Stock shall not be
entitled to cumulate their votes in any election of directors in which they are
entitled to vote and shall not be entitled to any preemptive rights to acquire
shares of any class or series of capital stock of the corporation.

                         ARTICLE 4. NO CUMULATIVE VOTING

     There shall be no cumulative voting by the shareholders of the corporation.

                         ARTICLE 5. NO PREEMPTIVE RIGHTS

     The shareholders of the corporation shall not have any preemptive rights to
subscribe for or acquire securities or rights to purchase securities of any
class, kind or series of the corporation.

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                     ARTICLE 6. WRITTEN ACTION BY DIRECTORS

     An action required or permitted to be taken at a meeting of the board of
directors of the corporation may be taken by a written action signed, or
counterparts of a written action signed in the aggregate, by all of the
directors unless the action need not be approved by the shareholders of the
corporation, in which case the action may be taken by a written action signed,
or counterparts of a written action signed in the aggregate, by the number of
directors that would be required to take the same action at a meeting of the
board of directors of the corporation at which all of the directors were
present.

                         ARTICLE 7. DIRECTOR LIABILITY

     To the fullest extent permitted by the Minnesota Business Corporation Act
as the same exists or may hereafter be amended, a director of this corporation
shall not be liable to this corporation or its shareholders for monetary damages
for breach of fiduciary duty as a director.

                                   ARTICLE 8.

     The Board of Directors shall have the power, to the extent permitted by
law, to adopt, amend or repeal the Bylaws of this corporation, subject to the
power of the shareholders to adopt, amend or repeal such Bylaws. Bylaws fixing
the number of directors or their classifications, qualifications or terms of
office, or prescribing procedures for removing directors or filling vacancies in
the Board may be adopted, amended or repealed only by the affirmative vote of
the holders of 80% of the outstanding shares of Common Stock entitled to vote.

     The number of directors shall be no less than three nor more than twenty
and shall be established by resolution of the Board of Directors. The number of
directors may be increased or decreased from time to time by a resolution
adopted by the holders of at least 80% of the outstanding shares of Common Stock
entitled to vote. In case of any increase or decrease in the number of
directors, the increase or decrease shall be distributed among the several
classes of directors as equally as possible as shall be determined by the Board
of Directors or by the holders of at least 80% of the outstanding shares of
Common Stock entitled to vote. The affirmative vote of shareholders holding at
least 80% of the outstanding shares of Common Stock entitled to vote at an
election of directors may remove any or all of the directors from office at any
time, with or without cause.

     Notwithstanding any other provisions of these Restated Articles of
Incorporation or the Bylaws of the corporation or the fact that a lesser
percentage may be specified by law, these Restated Articles of Incorporation or
the Bylaws of the corporation, the affirmative vote of the holders of at least
80% of outstanding shares of Common Stock entitled to vote shall be required to
amend or repeal all or any portion of this Article 8; provided, however, that if
the Continuing Directors shall by majority vote of all Continuing Directors have
adopted a resolution approving the amendment or repeal proposal and have
determined to recommend it for approval by the holders of Common Stock, then the
vote required shall be the affirmative vote of the holders of at least a
majority of the outstanding Common Stock entitled to vote.

     The term "Common Stock" shall mean the Common Stock, par value $.01 per
share, of the corporation.

     The term "Continuing Director" shall mean any member of the Board of
Directors of the corporation who is unaffiliated with a Controlling Person and
was a member of the Board prior to the time that the Controlling Person became a
Controlling Person, and any successor of a Continuing Director who is
unaffiliated with a Controlling Person and is recommended or elected to succeed
a Continuing Director by a majority of all Continuing Directors.

     The term "Controlling Person" shall mean any Person who beneficially owns a
number of shares of Common Stock, whether or not such number includes shares not
then issued, which exceeds a number equal to ten percent of the outstanding
shares of Common Stock.

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     The term "Person" shall mean an individual, a corporation, a partnership,
an association, a joint-stock company, a trust, any unincorporated organization
and any other entity or group.

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