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                                                                   Exhibit 10.10

                           DIAMETRICS MEDICAL, INC.
                             AMENDED AND RESTATED
                            1990 STOCK OPTION PLAN

1.   Purpose of Plan.
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          This Plan shall be known as the "DIAMETRICS MEDICAL, INC. 1990 STOCK
OPTION PLAN" and is hereinafter referred to as the "Plan." The purpose of the
Plan is to aid in maintaining and developing personnel capable of assuring the
future success of Diametrics Medical, Inc., a Minnesota corporation (the
"Company"), to offer such personnel additional incentives to put forth maximum
efforts for the success of the business, and to afford them an opportunity to
acquire a proprietary interest in the Company through stock options and other
long-term incentive awards as provided herein. Options granted under this Plan
may be either incentive stock options ("Incentive Stock Options") within the
meaning of Section 422 of the Internal Revenue Code of 1986 (the "Code"), or
options which do not qualify as Incentive Stock Options. Awards granted under
this Plan shall be SARs, restricted stock or performance awards as hereinafter
described.

2.   Stock Subject to Plan.
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          Subject to the provisions of Section 15 hereof, the stock to be
subject to options or other awards under the Plan shall be the Company's
authorized but unissued shares of Common Stock, par value $.01 per share. Such
shares may be either authorized but unissued shares, or issued shares which have
been reacquired by the Company. Subject to adjustment as provided in Section 15
hereof, the maximum number of shares on which options may be exercised or other
awards issued under this Plan shall be 3,000,000 shares. If an option or award
under the Plan expires, or for any reason is terminated or unexercised with
respect to any shares, such shares shall again be available for options or
awards thereafter granted during the term of the Plan.

3.   Administration of Plan.
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          (a) The Plan shall be administered by a committee (the "Committee") of
two or more members of the Board of Directors of the Company, none of whom shall
be officers or employees of the Company and all of whom shall be "disinterested
persons" with respect to the Plan within the meaning of Rule 16b-3 under the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), or any
successor rule or regulation thereto. The members of any such committee shall be
appointed by and serve at the pleasure of the Board of Directors.

          (b) The Committee shall have plenary authority in its discretion, but
subject to the express provisions of the Plan: (i) to determine the purchase
price of the Common Stock covered by each option or award, (ii) to determine the
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employees to whom and the time or times at which such options and awards shall
be granted and the number of shares to be subject to each, (iii) to determine
the form of payment to be made upon the exercise of an SAR or in connection with
performance awards, either cash, Common Stock of the Company or a combination
thereof, (iv) to determine the terms of exercise of each option and award, (v)
to accelerate the time at which all or any part of an option or award may be
exercised, (vi) to amend or modify the terms of any option or award with the
consent of the optionee, (vii) to interpret the Plan, (viii) to prescribe, amend
and rescind rules and regulations relating to the Plan, (ix) to determine the
terms and provisions of each option and award agreement under the Plan (which
agreements need not be identical), including the designation of those options
intended to be Incentive Stock Options, and (x) to make all other determinations
necessary or advisable for the administration of the Plan, subject to the
exclusive authority of the Board of Directors under Section 16 herein to amend
or terminate the Plan.

          (c) The Committee shall select one of its members as its Chairman and
shall hold its meetings at such times and places as it may determine. A majority
of its members shall constitute a quorum, provided that if the Committee is
comprised of no more than two members, all of its members must be present to
constitute a quorum. All determinations of the Committee shall be made by not
less than a majority of its members, provided that if the Committee is comprised
of no more than two members, such determinations may not be made by less than
all of its members. Any decision or determination reduced to writing and signed
by all of the members of the Committee shall be fully effective as if it had
been made by a majority vote at a meeting duly called and held. The grant of an
option or award shall be effective only if a written agreement shall have been
duly executed and delivered by and on behalf of the Company following such
grant. The Committee may appoint a Secretary and may make such rules and
regulations for the conduct of  business as it shall deem advisable.

          (d) The Chief Executive Officer of the Company shall have the
authority, as granted by the Committee pursuant to clause (ix) of subsection (b)
of this Section 3, to grant, pursuant to the Plan, options or other awards to
eligible persons who are not considered by the Company as its officers or
directors for purposes of Section 16 of the Securities Exchange Act of 1934, as
amended.  The Chief Executive Officer of the Company shall provide information
as to any grants made pursuant to this subsection to the Committee at their next
meeting.

4.   Eligibility.
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          Incentive Stock Options may only be granted under this Plan to any
full or part-time employee (which term as used herein includes, but is not
limited to, officers and directors who are also employees) of the Company and of
its present and future subsidiary corporations within the meaning of Section
424(f) of the Code

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(herein called "subsidiaries"). Full or part-time employees, consultants or
independent contractors to the Company or one of its subsidiaries shall be
eligible to receive options which do not qualify as Incentive Stock Options and
awards. In determining the persons to whom options and awards shall be granted
and the number of shares subject to each, the Committee may take into account
the nature of services rendered by the respective employees or consultant their
present and potential contributions to the success of the Company and such other
factors as the Committee in its discretion shall deem relevant. A person who has
been granted an option or award under this Plan may be granted additional
options or awards under the Plan if the Committee shall so determine; provided,
however, that for Incentive Stock Options granted after December 31, 1986, to
the extent the aggregate fair market value (determined at the time the Incentive
Stock Option is granted) of the Common Stock with respect to which all Incentive
Stock Options are exercisable for the first time by an employee during any
calendar year (under all plans described in subsection (d) of Section 422 of the
Code of his employer corporation and its parent and subsidiary corporations)
exceeds $100,000, such options shall be treated as options which do not qualify
as Incentive Stock Options. Nothing in the Plan or in any agreement thereunder
shall confer on any employee any right to continue in the employ of the Company
or any of its subsidiaries or affect, in any way, the right of the Company or
any of its subsidiaries to terminate his or her employment at any time.

5.   Price.
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          The option price for all Incentive Stock Options granted under the
Plan shall be determined by the Committee but shall not be less than 100% of the
fair market value of the Common Stock at the date of grant of such option. The
option price for options granted under the Plan which do not qualify as
Incentive Stock Options and, if applicable, the price for all awards shall also
be determined by the Committee. For purposes of the preceding sentence and for
all other valuation purposes under the Plan, the fair market value of shares of
Common Stock shall be (i) the closing price of the Common Stock as reported for
composite transactions if the Common Stock is then traded on a national
securities exchange, (ii) the last sale price if the Common Stock is then quoted
on the NASDAQ National Market System, or (iii) the average of the closing
representative bid and asked prices of the Common Stock as reported on NASDAQ on
the date as of which the fair market value is being determined. If on the date
of grant of any option or award hereunder the Common Stock is not traded on an
established securities market, the Committee shall make a good faith attempt to
satisfy the requirements of this Section 5 and in connection therewith shall
take such action as it deems necessary or advisable.

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6.   Term.
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          Each option and award and all rights and obligations thereunder shall
expire on the date determined by the Committee and specified in the option or
award agreement. The Committee shall be under no duty to provide terms of like
duration for options or awards granted under the Plan, but the term of an
Incentive Stock Option may not extend more than ten (10) years from the date of
grant of such option and the term of options granted under the Plan which do not
qualify as Incentive Stock Options may not extend more than fifteen (15) years
from the date of granting of such option.

7.   Exercise of Option or Award.
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          (a) The Committee shall have full and complete authority to determine
whether an option or award will be exercisable in full at any time or from time
to time during the term thereof, or to provide for the exercise thereof in such
installments, upon the occurrence of such events (such as termination of
employment for any reason) and at such times during the term of the option as
the Committee may determine and specify in the option or award agreement.

          (b) The exercise of any option or award granted hereunder shall only
be effective at such time that the sale of Common Stock pursuant to such
exercise will not violate any state or federal securities or other laws. Only to
the extent required in order to comply with Rule 16b-3 under the Exchange Act,
in the case of an option or other award granted to a person considered by the
Company as one of its officers or directors for purposes of Section 16 of the
Exchange Act, the terms of the option or other award will require that such
shares are not disposed of by such officer or director for a period of at least
six months from the date of grant.

          (c) An optionee or grantee electing to exercise an option or award
shall give written notice to the Company of such election and of the number of
shares subject to such exercise. The full purchase price of such shares shall be
tendered with such notice of exercise. Payment shall he made to the Company in
cash (including bank check, certified check, personal check, or money order),
or, at the discretion of the Committee and as specified by the Committee, (i) by
delivering certificates for the Company's Common Stock already owned by the
optionee or grantee having a fair market value as of the date of grant equal to
the full purchase price of the shares, or (ii) by delivering the optionee's or
grantee's promissory note, which shall provide for interest at a rate not less
than the minimum rate required to avoid the imputation of income, original issue
discount or a below-market-rate loan pursuant to Sections 483, 1274 or 7872 of
the Code or any successor provisions thereto, or (iii) a combination of cash,
the optionee's or grantee promissory note and such shares. The fair market value
of such tendered shares shall be determined as provided in Section 5 herein. The
optionee's or grantee's promissory note shall be a

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full recourse liability of the optionee and may, at the discretion of the
Committee, be secured by a pledge of the shares being purchased. Until such
person has been issued the shares subject to such exercise, he or she shall
possess no rights as a shareholder with respect to such shares.

8.   Stock Appreciation Rights.
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          (a) Grant.  At the time of grant of an option or award under the Plan
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(or at any other time), the Committee, in its discretion, may grant a Stock
Appreciation Right ("SAR") evidenced by an agreement in such form as the
Committee shall from time to time approve. Any such SAR may be subject to
restrictions on the exercise thereof as may be set forth in the agreement
representing such SAR, which agreement shall comply with and be subject to the
following terms and conditions and any additional terms and conditions
established by the Committee that are consistent with the terms of the Plan.

          (b) Exercise.  An SAR shall be exercised by the delivery to the
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Company of a written notice which shall state that the holder thereof elects to
exercise his or her SAR as to the number of shares specified in the notice and
which shall further state what portion, if any, of the SAR exercise amount
(hereinafter defined) the holder thereof requests be paid to in cash and what
portion, if any, is to be paid in Common Stock of the Company. The Committee
promptly shall cause to be paid to such holder the SAR exercise amount either in
cash, in Common Stock of the Company, or any combination of cash and shares as
the Committee may determine. Such determination may be either in accordance with
the request made by the holder of the SAR or in the sole and absolute discretion
of the Committee. The SAR exercise amount is the excess of the fair market value
of one share of the Company's Common Stock on the date of exercise over the per
share exercise price in respect of which the SAR was granted, multiplied by the
number of shares as to which the SAR is exercised. For the purposes hereof, the
fair market value of the Company's shares of Common Stock shall be determined as
provided in Section 5 herein.

9.   Restricted Stock Awards.
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          Awards of Common Stock subject to forfeiture and transfer restrictions
may be granted by the Committee. Any restricted stock award shall be evidenced
by an agreement in such form as the Committee shall from time to time approve,
which agreement shall comply with and be subject to the following terms and
conditions and any additional terms and conditions established by the Committee
that are consistent with the terms of the Plan:

          (a) Grant of Restricted Stock Awards. Each restricted stock award made
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under the Plan shall be for such number of shares of Common Stock as shall

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be determined by the Committee and set forth in the agreement containing the
terms of such restricted stock award. Such agreement shall set forth a period of
time during which the grantee must remain in the continuous employment of the
Company in order for the forfeiture and transfer restrictions to lapse. If the
Committee so determines, the restrictions may lapse during such restricted
period in installments with respect to specified portions of the shares covered
by the restricted stock award. The agreement may also, in the discretion of the
Committee, set forth performance or other conditions that will subject the
Common Stock to forfeiture and transfer restrictions. The Committee may, at its
discretion, waive all or any part of the restrictions applicable to any or all
outstanding restricted stock awards.

          (b) Delivery of Common Stock and Restrictions. At the time of a
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restricted stock award, a certificate representing the number of shares of
Common Stock awarded thereunder shall be registered in the name of the grantee.
Such certificate shall be held by the Company or any custodian appointed by the
Company for the account of the grantee subject to the terms and conditions of
the Plan, and shall bear such a legend setting forth the restrictions imposed
thereon as the Committee, in its discretion, may determine. The grantee shall
have all rights of a shareholder with respect to the Common Stock, including the
right to receive dividends and the right to vote such shares, subject to the
following restrictions: (i) the grantee shall not be entitled to delivery of the
stock certificate until the expiration of the restricted period and the
fulfillment of any other restrictive conditions set forth in the restricted
stock agreement with respect to such Common Stock; (ii) none of the shares of
Common Stock may be sold, assigned, transferred, pledged, hypothecated or
otherwise encumbered or disposed of during such restricted period or until after
the fulfillment of any such other restrictive conditions; and (iii) except as
otherwise determined by the Committee, all of the Common Stock shall be
forfeited and all rights of the grantee to such Common Stock shall terminate,
without further obligation on the part of the Company, unless the grantee
remains in the continuous employment of the Company for the entire restricted
period in relation to which such shares of Common Stock were granted and unless
any other restrictive conditions relating to the restricted stock award are met.
Any Common Stock, any other securities of the Company and any other property
(except for cash dividends) distributed with respect to the Common Stock subject
to restricted stock awards shall be subject to the same restrictions, terms and
conditions as such restricted Common Stock.

          (c) Termination of Restrictions.  At the end of the restricted period
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and provided that any other restrictive conditions of the restricted stock award
are met, or at such earlier time as otherwise determined by the Committee, all
restrictions set forth in the agreement relating to the restricted stock award
or in the Plan shall lapse as to the restricted Common Stock subject thereto,
and a stock certificate for the appropriate number of shares of Common Stock,
free of the

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restrictions and the restricted stock legend, shall be delivered to the grantee
or his beneficiary or estate, as the case may be.

10.  Performance Awards.
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          The Committee is further authorized to grant performance awards
("Performance Award"). Subject to the terms of this Plan and any applicable
award agreement, Performance Awards granted under the Plan (i) may be
denominated or payable in cash, Common Stock (including, without limitation,
restricted stock), other securities, other awards, or other property and (ii)
shall confer on the holder thereof rights valued as determined by the Committee,
in its discretion, and payable to, or exercisable by, the holder of the
Performance Awards, in whole or in part, upon the achievement of such
performance goals during such performance periods as the Committee, in its
discretion, shall establish. Subject to the terms of this Plan and any
applicable award agreement, the performance goals to be achieved during any
performance period, the length of any performance period, the amount of any
Performance Awards granted, and the amount of any payment or transfer to be made
by the grantee and by the Company under any Performance Awards shall be
determined by the Committee.

11.  Income Tax Withholding and Tax Bonuses.
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          (a) In order to comply with all applicable federal or state income tax
laws or regulations, the Company may take such action as it deems appropriate to
ensure that all applicable federal or state payroll, withholding, income or
other taxes, which are the sole and absolute responsibility of an optionee or
grantee under the Plan, are withheld or collected from such optionee or grantee.
In order to assist an optionee or grantee in paying all federal and state taxes
to be withheld or collected upon exercise of an option or award which does not
qualify as an Incentive Stock Option hereunder, the Committee, in its absolute
discretion and subject to such additional terms and conditions as it may adopt,
shall permit the optionee or grantee to satisfy such tax obligation by (i)
electing to have the Company withhold a portion of the shares otherwise to be
delivered upon exercise of such option or award with a fair market value,
determined in accordance with Section 5 herein, equal to such taxes or (ii)
delivering to the Company Common Stock other than the shares issuable upon
exercise of such option or award with a fair market value, determined in
accordance with Section 5, equal to such taxes.

          (b) The Committee shall have the authority, at the time of grant of an
option under the Plan or at any time thereafter, to approve tax bonuses to
designated optionees or grantees to be paid upon their exercise of options or
awards granted hereunder. The amount of any such payments shall be determined by
the Committee. The Committee shall have full authority in its absolute
discretion to

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determine the amount of any such tax bonus and the terms and conditions
affecting the vesting and payment thereafter.

12.  Additional Restrictions.
     -----------------------

          The Committee shall have full and complete authority to determine
whether all or any part of the Common Stock of the Company acquired upon
exercise of any of the options or awards granted under the Plan shall be subject
to restrictions on the transferability thereof or any other restrictions
affecting in any manner the optionee's or grantee's rights with respect thereto,
but any such restriction shall be contained in the agreement relating to such
options or awards.

13.  Ten Percent Shareholder Rule.
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          Notwithstanding any other provision in the Plan, if at the time an
option is otherwise to be granted pursuant to the Plan the optionee owns
directly or indirectly (within the meaning of Section 424(d) of the Code) Common
Stock of the Company possessing more than ten percent (10%) of the total
combined voting power of all classes of stock of the Company or its parent or
subsidiary corporations, if any (within the meaning of Section 422(b)(6) of the
Code), then any Incentive Stock Option to be granted to such optionee pursuant
to the Plan shall satisfy the requirements of Section 422(c)(5) of the Code, and
the option price shall be not less than 110% of the fair market value of the
Common Stock of the Company determined as described herein, and such option by
its terms shall not be exercisable after the expiration of five (5) years from
the date such option is granted.

14.  Non-Transferability.
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          No option may be sold, pledged, assigned, hypothecated, transferred,
or disposed of in any manner other than (i) by will or by the laws of descent or
distribution, or (ii) in the case of options that are not Incentive Stock
Options, to members of the optionee's immediate family or to one or more trusts
for the benefit of the optionee or members of his or her immediate family, and
the option may be exercised, during the lifetime of the Optionee, only by the
optionee or a permitted transferee.

15.  Dilution or Other Adjustments.
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          If there shall be any change in the Common Stock through merger,
consolidation, reorganization, recapitalization, dividend in the form of stock
(of whatever amount), stock split or other change in the corporate structure,
appropriate adjustments in the Plan and outstanding options and awards shall be
made by the Committee. In the event of any such changes, adjustments shall
include, where appropriate, changes in the aggregate number of shares subject to
the

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Plan, the number of shares and the price per share subject to outstanding
options and awards and the amount payable upon exercise of outstanding awards,
in order to prevent dilution or enlargement of option or award rights.

16.  Amendment or Discontinuance of Plan.
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          The Board of Directors may amend or discontinue the Plan at any time.
Subject to the provisions of Section 15 no amendment of the Plan, however, shall
without shareholder approval:  (i) increase the maximum number of shares under
the Plan as provided in Section 2 herein, (ii) decrease the minimum price
provided in Section 5 herein, (iii) extend the maximum term under Section 6, or
(iv) modify the eligibility requirements for participation in the Plan. The
Board of Directors shall not alter or impair any option or award theretofore
granted under the Plan without the consent of the holder of the option.

17.  Time of Granting.
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          Nothing contained in the Plan or in any resolution adopted or to be
adopted by the Board of Directors or by the shareholders of the Company, and no
action taken by the Committee or the Board of Directors (other than the
execution and delivery of an option or award agreement), shall constitute the
granting of an option or award hereunder.

18.  Effective Date and Termination of Plan.
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          (a) The Plan was approved by the Board of Directors on June 29, 1990
and shall be approved by the shareholders of the Company within twelve (12)
months thereof.

          (b) Unless the Plan shall have been discontinued as provided in
Section 16 hereof, the Plan shall terminate June 29, 2005. No option or award
may be granted after such termination, but termination of the Plan shall not,
without the consent of the optionee or grantee, alter or impair any rights or
obligations under any option or award theretofore granted.

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