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                                                                   EXHIBIT 10.37


                     SECOND AMENDMENT AND RELEASE AGREEMENT


         THIS SECOND AMENDMENT AND RELEASE AGREEMENT (this "Agreement"), dated
as of February 20, 2001, is entered into by and among AMERICAN MEDICAL SYSTEMS,
INC., a Delaware corporation (the "Borrower"), each of the Persons identified as
a "Guarantor" on the signature pages hereto, each of the Persons identified as a
"Lender" on the signature pages hereto and BANK OF AMERICA, N.A., as Agent for
the Lenders (in such capacity, the "Agent").

                                    RECITALS

         A.       The Borrower, the Guarantors, the Lenders and the Agent, are
party to that certain Credit Agreement dated as of March 24, 2000 (as previously
amended prior to the date hereof, the "Credit Agreement"). Unless otherwise
defined herein or the context otherwise requires, capitalized terms used in this
Agreement, including its preamble and recitals, have the meanings provided in
the Credit Agreement.

         B.       The Credit Parties have requested that the Lenders release the
Warburg Guaranty.

         C.       The Lenders have agreed to release the Warburg Guaranty on the
terms and conditions hereinafter set forth.

         NOW, THEREFORE, in consideration of the agreements herein contained,
the parties hereto hereby agree as follows:

         1.       Amendments.

         (a)      The definitions of "Applicable Percentage" and "Leverage
Ratio" appearing in Section 1.1 of the Credit Agreement are hereby amended and
restated in their entireties to read as follows:

                  "Applicable Percentage" means, for purposes of calculating the
         applicable interest rate for any day for any Loan, the applicable rate
         of the Unused Fee for any day for purposes of Section 3.5(a), the
         applicable rate of the Standby Letter of Credit Fee for any day for
         purposes of Section 3.5(b)(i) or the applicable rate of the Trade
         Letter of Credit Fee for any day for purposes of Section 3.5(b)(ii),
         the appropriate applicable percentage corresponding to the Leverage
         Ratio in effect as of the most recent Calculation Date:


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<TABLE>
<CAPTION>


============== ================ ====================================================================================================
                                                                         APPLICABLE PERCENTAGES
                                ----------------------------------------------------------------------------------------------------
                                     FOR REVOLVING LOANS
                                     AND TRANCHE A TERM           FOR TRANCHE B TERM
                                            LOANS                       LOANS
                                ---------------------------- -----------------------------
                                                                                                FOR          FOR TRADE        FOR
   PRICING         LEVERAGE         EURODOLLAR      BASE        EURODOLLAR        BASE        STANDBY        LETTER OF      UNUSED
    LEVEL           RATIO             LOANS         RATE          LOANS           RATE       LETTER OF      CREDIT FEE        FEE
                                                    LOANS                         LOANS     CREDIT FEE
-------------- ---------------- ----------------- ---------- ---------------- ------------ --------------  -------------  ----------
<S>            <C>              <C>               <C>        <C>              <C>          <C>             <C>            <C>

      I         > 3.0 to 1.0         3.00%          2.00%        0.875%           0%           3.00%           1.50%        0.25%
-------------- ---------------- ----------------- ---------- ---------------- ------------ --------------  -------------  ----------
                < 3.0 to 1.0
                -
     II         but > 2.5 to         2.50%          1.50%        0.875%           0%           2.50%           1.25%        0.25%
                     1.0
-------------- ---------------- ----------------- ---------- ---------------- ------------ -----------------------------------------
     III        < 2.5 to 1.0         2.00%          1.00%        0.875%           0%           2.00%           1.00%        0.25%
                -
============== ================ ================= ========== ================ ============ =========================================

</TABLE>

         The Applicable Percentages shall be determined and adjusted quarterly
         on the date (each a "Calculation Date") five Business Days after the
         date by which the Credit Parties are required to provide the officer's
         certificate in accordance with the provisions of Section 7.1(c) for the
         most recently ended fiscal quarter of the Consolidated Parties;
         provided, however, that (i) the initial Applicable Percentages shall be
         based on Pricing Level I (as shown above) and shall remain at Pricing
         Level I until the Calculation Date for the fiscal quarter of the
         Consolidated Parties ending on September 30, 2000, on and after which
         time the Pricing Level shall be determined by the Leverage Ratio as of
         the last day of the most recently ended fiscal quarter of the
         Consolidated Parties preceding the applicable Calculation Date and (ii)
         if the Credit Parties fail to provide the officer's certificate to the
         Agency Services Address as required by Section 7.1(c) for the last day
         of the most recently ended fiscal quarter of the Consolidated Parties
         preceding the applicable Calculation Date, the Applicable Percentage
         from such Calculation Date shall be based on Pricing Level I until such
         time as an appropriate officer's certificate is provided, whereupon the
         Pricing Level shall be determined by the Leverage Ratio as of the last
         day of the most recently ended fiscal quarter of the Consolidated
         Parties preceding such Calculation Date. Each Applicable Percentage
         shall be effective from one Calculation Date until the next Calculation
         Date. Any adjustment in the Applicable Percentages shall be applicable
         to all existing Loans and Letters of Credit as well as any new Loans
         and Letters of Credit made or issued.

                  "Leverage Ratio" means, as of the end of any fiscal quarter of
         the Consolidated Parties for the four fiscal quarter period ending on
         such date with respect to the Consolidated Parties on a consolidated
         basis, the ratio of (a) Funded Indebtedness of the Consolidated Parties
         on a consolidated basis on the last day of such period to (b)
         Consolidated EBITDA for such period.


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         (b)      Section 2.3(d) of the Credit Agreement is hereby amended and
restated in its entirety to read as follows:

                  (d) Repayment of Tranche A Term Loan. The principal amount of
         the Tranche A Term Loan shall be repaid in twenty-two (22) consecutive
         quarterly installments as follows unless accelerated sooner pursuant to
         Section 9.2:

<TABLE>
<CAPTION>


================================ ==============================
                                         TRANCHE A TERM
          PRINCIPAL                      LOAN PRINCIPAL
         AMORTIZATION                     AMORTIZATION
        PAYMENT DATES                        PAYMENT
-------------------------------- ------------------------------
<S>                              <C>
        March 31, 2001                   $1,508,203.28
-------------------------------- ------------------------------
        June 30, 2001,
      September 30, 2001,                  $1,508,200
     December 31, 2001 and
        March 31, 2002
-------------------------------- ------------------------------
        June 30, 2002,
      September 30, 2002,                  $1,885,200
     December 31, 2002 and
        March 31, 2003
-------------------------------- ------------------------------
        June 30, 2003,
      September 30, 2003,                  $2,262,300
     December 31, 2003 and
        March 31, 2004
-------------------------------- ------------------------------
        June 30, 2004,
      September 30, 2004,
      December 31, 2004
        March 31, 2005,
        June 30, 2005,                     $2,545,100
      September 30, 2005,
     December 31, 2005 and
         Maturity Date
================================ ==============================
</TABLE>



         (c)      (i) The clause "and in Section 10 of the Warburg Guaranty"
appearing in Section 5.3(b) of the Credit Agreement is hereby deleted, (ii)
Section 9.1(j) of the Credit Agreement is hereby amended and restated in its
entirety to read as follows: "(j) [intentionally omitted];" (iii) Section
11.3(e) of the Credit Agreement is hereby amended by replacing the last clause
thereof with "(F) [intentionally omitted].", (iv) Section 11.6(a)(ix) is hereby
amended and restated in its entirety to read as follows: "(ix) [Intentionally
Omitted];" and (v) Section 11.6(e) of the Credit Agreement is hereby amended by
replacing clause (B) thereof with "(B) [intentionally omitted]".


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<PAGE>   4

        (d)       Section 7.11(c) of the Credit Agreement is hereby amended
and restated in its entirety to read as follows

                  (c)     Fixed Charge Coverage Ratio. The Fixed Charge Coverage
         Ratio, as of the last day of each fiscal quarter of the Consolidated
         Parties indicated below, shall be greater than or equal to the ratio
         indicated with respect to such date:

<TABLE>
<CAPTION>

                           ======================================= =======================================
                                     FISCAL QUARTER END                   FIXED CHARGE COVERAGE RATIO
                           --------------------------------------- ---------------------------------------
                           <S>                                     <C>
                                    Closing Date through
                                     December 31, 2000                         1.00 to 1.00
                           --------------------------------------- ---------------------------------------
                               March 31, 2001 and each fiscal
                                   quarter-end thereafter                      1.25 to 1.00
                           ======================================= =======================================

</TABLE>

         2.       Release. The Lenders hereby release the WPEP Entities from
their obligations under the Warburg Guaranty. In connection with such release of
the Warburg Guaranty, the Lenders authorize the Agent to deliver to the WPEP
Entities, at the Credit Parties' expense, such documentation as is reasonably
necessary to evidence the release of the Warburg Guaranty. This paragraph shall
be for the benefit of and may be enforced by the WPEP Entities.

         3.       Effective Date. This Agreement shall be and become effective
as of the date hereof at such time as the Agent shall have received executed
counterparts (including facsimile signatures) of this Agreement, which
collectively shall have been duly executed on behalf of each of the Credit
Parties and the Lenders.

         4.       Construction. This Agreement is a Credit Document executed
pursuant to the Credit Agreement and shall (unless otherwise expressly indicated
therein) be construed, administered and applied in accordance with the terms and
provisions of the Credit Agreement.

         5.       Representations and Warranties. Each Credit Party hereby
represents and warrants that (i) each Credit Party that is party to this
Agreement: (a) has the requisite corporate power and authority to execute,
deliver and perform this Agreement, as applicable and (b) is duly authorized to,
and has been authorized by all necessary corporate action, to execute, deliver
and perform this Agreement, (ii) the representations and warranties contained in
Section 6 of the Credit Agreement are true and correct in all material respects
on and as of the date hereof upon giving effect to this Agreement as though made
on and as of such date (except for those which expressly relate to an earlier
date) and (iii) no Default or Event of Default exists under the Credit Agreement
on and as of the date hereof upon giving effect to this Agreement.

         6.       Acknowledgment. The Guarantors acknowledge and consent to all
of the terms and conditions of this Agreement and agree that this Agreement does
not operate to reduce or discharge the Guarantors' obligations under the Credit
Agreement or the other Credit Documents. The Guarantors further acknowledge and
agree that the Guarantors have no claims, counterclaims, offsets, or defenses to
the Credit Documents and the performance of the Guarantors' obligations


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thereunder or if the Guarantors did have any such claims, counterclaims, offsets
or defenses to the Credit Documents or any transaction related to the Credit
Documents, the same are hereby waived, relinquished and released in
consideration of the Lenders' execution and delivery of this Agreement.

         7.       Counterparts. This Agreement may be executed by the parties
hereto in several counterparts, each of which shall be deemed to be an original
and all of which shall constitute together but one and the same agreement.

         8.       Binding Effect. This Agreement, the Credit Agreement and the
other Credit Documents embody the entire agreement between the parties and
supersede all prior agreements and understandings, if any, relating to the
subject matter hereof. These Credit Documents represent the final agreement
between the parties and may not be contradicted by evidence of prior,
contemporaneous or subsequent oral agreements of the parties. Except as
expressly modified and amended in this Agreement, all the terms, provisions and
conditions of the Credit Documents shall remain unchanged and shall continue in
full force and effect.

         9.       GOVERNING LAW. THIS AGREEMENT AND THE RIGHTS AND OBLIGATIONS
OF THE PARTIES HEREUNDER SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH
THE LAWS OF THE STATE OF NEW YORK.

                [Remainder of page is intentionally left blank.]


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                                                                   EXHIBIT 10.37

         IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart
of this Agreement to be duly executed and delivered as of the date first above
written.


BORROWER:                        AMERICAN MEDICAL SYSTEMS, INC.



                                 By:    /s/ Gregory J. Melsen
                                 Name:  Gregory J. Melsen
                                      -------------------------------
                                 Title: Vice President-Finance, Treasurer
                                       ----------------------------------
                                       and Chief Financial Officer
                                       ----------------------------



GUARANTORS:                      AMERICAN MEDICAL SYSTEMS HOLDINGS, INC.



                                 By:    /s/ Gregory J. Melsen
                                 Name:  Gregory J. Melsen
                                      -------------------------------
                                 Title: Vice President-Finance, Treasurer
                                       ----------------------------------
                                       and Chief Financial Officer
                                       -------------------------------

                                 AMERICAN MEDICAL SYSTEMS
                                 INTERNATIONAL, INC. FORMERLY INFLUENCE, INC.)



                                 By:    /s/ Gregory J. Melsen
                                 Name:  Gregory J. Melsen
                                      -------------------------------
                                 Title: Vice President-Finance, Treasurer
                                       ----------------------------------
                                       and Chief Financial Officer
                                       -------------------------------



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LENDERS:                                    BANK OF AMERICA, N. A.,
                                            individually in its capacity as a
                                            Lender and in its capacity as Agent

                                            By:    /s/ Kip Davis
                                            Name:  Kipling E. Davis
                                            Title: Vice President


                                            BANKERS TRUST COMPANY


                                            By:    /s/ Scottye D. Lindsey
                                            Name:  Scottye D. Lindsey
                                            Title: Vice President



                                            U.S. BANK NATIONAL ASSOCIATION

                                            By:    /s/ Mark R. Olmon
                                            Name:  Mark R. Olmon
                                            Title: Senior Vice President



                                            FLEET NATIONAL BANK

                                            By:    /s/ Garth J. Collin
                                            Name:  Garth J. Collin
                                            Title: Senior Vice President


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