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                                                                   EXHIBIT 10.5


                                 AMENDMENT NO. 1
                                       TO
                        DEVELOPMENT AND SUPPLY AGREEMENT

          This Amendment No. 1, effective as of December 22, 2000, is to that
certain Development and Supply Agreement (the "Agreement"), dated as of
January 5, 2000, by and between MacroPore, Inc., a Delaware corporation
("MacroPore") and Medtronic, Inc. ("Medtronic"), a Minnesota corporation.

          WHEREAS, MacroPore and Medtronic desire to amend the Agreement as
set forth below.

          NOW, THEREFORE, for good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, the parties, hereby agree
as follows:

     1.   Section 6.1 (Prices) of the Agreement shall be deleted in its
entirety and the following inserted in its place.

                  "Section 6.1)     PRICES.

                   (a)      Unless and until otherwise mutually agreed upon by
                            the parties in writing, the purchase price per
                            unit of Developed Products to Medtronic (the
                            "Transfer Price") under this Agreement shall be
                            based on the price list in effect at the time of
                            receipt of the order (the "Price List") to be set
                            forth on Exhibit B to this Agreement.  The Price
                            List shall be reviewed by MacroPore and Medtronic
                            on the six month anniversary of the date of the
                            initial Price List and every six months
                            thereafter, with any changes to the Price List to
                            take effect upon delivery of the revised Price
                            List to Medtronic.  New Developed Products may be
                            added to the Price List at any time by 30 day
                            prior written notice to Medtronic.  In the event
                            MacroPore and Medtronic's review of the Price
                            List results in a change to the Transfer Price
                            for any of the Developed Products on the Price
                            List, all such changes will apply to the Transfer
                            Price of future sales and shall not be applied
                            retroactively to previous sales of that Developed
                            Product to Medtronic.  Separate Transfer Prices
                            will be established for sales in the United
                            States and for sales in the international market.
                             The prices for customized products are not
                            included in the Price List but shall be
                            determined in accordance with Section 5.8 herein.

                   (b)      MacroPore will establish the Price List (i) for
                            Developed Products that are Spinal Implants based
                            on [***]of the

PORTIONS OF THIS EXHIBIT MARKED AS [***] HAVE BEEN OMITTED PURSUANT TO A
REQUEST FOR CONFIDENTIAL TREATMENT. THE OMITTED MATERIAL HAS BEEN FILED
SEPARATELY WITH THE SEC.


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                            estimated average selling price per unit for each
                            Product, excluding any sales, use or excise tax,
                            freight, duty or insurance included therein and
                            (ii) for Developed Products that are
                            [*************] based on [***] of the estimated
                            average selling price per unit for each Product,
                            excluding any sales, use or excise tax, freight,
                            duty or insurance included therein; provided that
                            in no event shall the Transfer Price for any
                            Developed Product be less than [***] of
                            MacroPore's per unit direct cost of manufacturing.

                   (c)      If Medtronic sells the Developed Product as part
                            of a packaged combination of products or
                            instruments, then Medtronic's sale price of the
                            Developed product shall equal either (i) the
                            respective average net selling price during such
                            period of the same type of Developed Product sold
                            individually, or (ii) the average net selling
                            price during such period for a comparable product
                            (if the same type of Developed Product is not
                            sold individually).

                   (d)      Medtronic and MacroPore agree to keep accurate
                            written records sufficient in detail to enable
                            Medtronic's average selling price and MacroPore's
                            direct cost of manufacturing, respectively, of
                            Developed Products to be determined and verified.
                             Such records for a particular quarter shall be
                            retained for a period of not less than three
                            years.  Upon reasonable notice and during regular
                            business hours, each party shall from time to
                            time (but no more frequently than once annually)
                            make available such records for audit at the
                            other party's expense by independent
                            representatives selected by such other party to
                            verify the accuracy of the reports provided to
                            such other party.  Such representatives shall
                            execute a suitable confidentiality agreement
                            reasonable acceptable to the party whose records
                            are being audited prior to conducting such audit.
                            Such representatives may disclose to such other
                            party only their conclusions regarding the
                            accuracy and completeness of records related
                            thereto, and shall not disclose confidential
                            business information to such other party without
                            the prior written consent of Medtronic.

     2. The Agreement will be amended by inserting Exhibit B immediately
after Exhibit A to the Agreement as soon as Exhibit B becomes available.

     3. Except as amended hereby, the Agreement shall remain unchanged and in
full force and effect.


PORTIONS OF THIS EXHIBIT MARKED AS [***] HAVE BEEN OMITTED PURSUANT TO A
REQUEST FOR CONFIDENTIAL TREATMENT. THE OMITTED MATERIAL HAS BEEN FILED
SEPARATELY WITH THE SEC.


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     4. This Amendment No. 1 and the Agreement constitute the entire
agreement among the parties hereto with respect to the subject matter hereof,
and supersede any and all prior agreements and undertakings, oral or written,
concerning the subject matter hereof. This Agreement may not be changed or
terminated orally, and may only be changed or terminated by a writing signed
by the party against whom such change or termination is sought.

     5. This Amendment No. 1 may be executed in any number of counterparts
and by facsimile, each of which, when executed, shall be deemed to be an
original and all of which together shall be deemed to be one and the same
instrument.

                              *  *  *  *  *

     IN WITNESS WHEREOF, this Amendment No. 1 has been duly executed by the
parties as of the date first set forth above.

                                            MACROPORE, INC.,
                                            a Delaware corporation


                                            By:      /s/ Charles E. Galetto
                                                     -----------------------
                                            Name:    Charles E. Galetto
                                            Its:     VP - Finance


                                            MEDTRONIC, INC.,
                                            a Minnesota corporation


                                            By:      /s/ Michael D. Ellwein
                                                     -----------------------
                                            Name:    Michael D. Ellwein
                                            Its:     Vice President and Chief
                                                     Development Officer



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