EXHIBIT 3.12
 
                                  REGULATIONS

                                      OF 

                   DIALYSIS SPECIALISTS OF SOUTH TEXAS, LLC.

                                   ARTICLE I

                           OFFICES AND COMPANY SEAL
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     1.   PRINCIPAL OFFICE.  The principal office of the Company shall be 
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located at 4300 2-1 South Padre Island Drive, Corpus Christi, Texas.

     2.   OTHER OFFICES.  The Company may also maintain offices at such other 
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place or places, within the State of Texas, as may be designated from time to 
time by the Members of the Company, and the business of the Company may be 
transacted at such other offices with the same effect as that conducted at the 
principal office.

     3.   COMPANY SEAL.  A company seal shall not be requisite to the validity 
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of any instrument executed by or on behalf of the Company, but may be used.

                                  ARTICLE II

                                  FISCAL YEAR
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     1.   FISCAL YEAR.  The fiscal year of the Company shall begin on the first 
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day of January and end on the last day of December.

                                  ARTICLE III

                                    MEMBERS
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     1.   POWERS.  The business and affairs of the Company shall be managed by 
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its Members.

     2.   PLACE OF MEETINGS.  The Members of the Company may hold meetings, both
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regular and special, either within or without the State of Texas.

     3.   ANNUAL MEETINGS.  The annual meeting of the members shall be held the 
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first Wednesday in March if not a legal holiday, and if a legal holiday, then on
the next secular day following, or at such other date and time as shall be 
designated from time to time by the members and stated in the notice of the
meeting. At the annual meeting, members shall elect Officers and transact such
other business as may properly be brought before the meeting.

Limited Liability Company Regulations

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     4.   REGULAR MEETINGS. Regular meetings of the Members may be held without 
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notice at such time and at such place as shall from time to time be determined 
by the Members.

     5.   SPECIAL MEETINGS. Special meetings of the Members may be called by the
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President or the Secretary on one (1) day's notice to each Member, either 
personally, by mail, by telegram, or by telephone; special meetings shall be 
called by the President or Secretary in like manner and on like notice on the 
written request of a majority of Members.

     6.   QUORUM: ADJOURNMENT: MAJORITY REQUIRED. A majority of the Members of 
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the Company shall constitute a quorum. The concurrence of a majority of those 
present shall be sufficient to conduct the business of the Company, except as 
may be otherwise specifically provided by statute, the Articles of Organization 
or these Regulations. If a quorum shall not be present at any meeting of the 
Members, the Members then present may adjourn the meeting to another time or 
place, without notice other than announcement at the meeting, until a quorum 
shall be present.

     7.   ACTION WITHOUT MEETING. Unless otherwise restricted by the Articles of
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Organization or these Regulations, any action required or permitted to be taken 
at any meeting of the Members or of any committee thereof may be taken without a
meeting, if all Members or members of the committee, as the case may be, consent
thereto in writing, and the writing or writings are filed with the minutes of 
proceedings of the Members or committee.

     8.   COMPENSATION. The Members may be paid their expenses, if any, of 
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attendance at each meeting of the Members and may be paid a fixed sum for 
attendance at each meeting of the Members or a stated salary for a Member. No 
such payment shall preclude any Member from serving the Company in any other 
capacity and receiving compensation therefor. Members of special or standing 
committees may be allowed like compensation for attending committee meetings. 
The amount or rate of such compensation of Members or of Committees shall be 
established by the Members and shall be set forth in the minutes of the meeting.

     9.   WAIVER OF NOTICE. Attendance of a Member at a meeting shall constitute
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waiver of notice of such meeting, except when the person attends the meeting for
the express purpose of objecting to the transaction of any business because the 
meeting is not lawfully called or convened. Any Member may waive notice of any 
annual, regular, or special meeting of Members by executing a written waiver of 
notice either before or after the time of the meeting.

                                  ARTICLE IV

                                   OFFICERS
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     1.   DESIGNATION OF TITLES. The officers of the Company shall be chosen by 
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the Members and shall be a President, a Vice President, a Secretary, and a 
Treasurer. Any

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number of offices, except the offices of President and Secretary, may be held by
the same person, unless the Articles of Organization or these Regulations
otherwise provide.

     2.  APPOINTMENT OF OFFICERS. At their annual meeting, the Members shall
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choose a President, one or more Vice Presidents, a Secretary and a Treasurer,
each of whom shall serve at the pleasure of the Members. The President and
Secretary shall be a different person. The Members at any time may appoint such
other officers and agents as they shall deem necessary to hold offices at the
pleasure of the Members and to exercise such powers and perform such duties as
shall be determined from time to time by the Members.

     3.  SALARIES. The salaries of the officers shall be fixed from time to time
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by the Members, and no officer shall be prevented from receiving such salary by
reason of the fact that he is also a Member. The salaries of the officers or 
the rate by which salaries are fixed shall be set forth in the minutes of the 
meetings of the Members.

     4.  VACANCIES. A vacancy in any office because of death, resignation, 
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removal, disqualification or otherwise may be filled by the Members at any time.

     5.  PRESIDENT. The President shall preside at all meetings of Members. He
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or she shall sign all deeds and conveyances, all contracts and agreements, and
all other instruments requiring execution on behalf of the Company, and shall 
act as operating and directing head of the Company, subject to policies 
established by the Members. 
     
     6.  VICE PRESIDENT. There shall be as many Vice Presidents as shall be 
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determined by the Members from time to time, and they shall perform such duties
as from time to time may be assigned to them. Any one of the Vice Presidents, as
authorized by the Members, shall have all the powers and perform all the duties
of the President in case of the temporary absence of the President or in case of
his or her temporary inability to act. In case of the permanent absence or
inability of the President to act, the office shall be declared vacant by the
Members and a successor chosen by the Members.

     7.  SECRETARY. The Secretary shall see that the minutes of all meetings
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of the Members, and of any standing committees are kept. He or she shall be the
custodian of the company seal and shall affix it to all proper instruments
when deemed advisable by him or her. He or she shall give or cause to be given
required notices of all meetings of the Members. He or she shall have charge of
all the books and records of the Company except the books of account, and in
general shall perform all the duties incident to the office of Secretary of a
Company and such other duties as may be assigned to him or her.
   
     8.  TREASURER. The Treasurer shall have general custody of all the funds
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and securities of the Company except such as may be required by law to be 
deposited with any state official. He or she shall see to the deposit of the 
funds of the Company in such bank or banks as the Members may designate. Regular
books of account shall be kept under his or her direction and supervision, and 
he or she shall render financial statements to the President, and Members at 
proper times. The Treasurer shall have charge of the preparation and filing of
such reports, financial statements, and returns as may be required by law. He
or she shall give to the Company such fidelity bond as may be required, and the 
premium therefore shall

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be paid by the Company as an operating expense.

     9.   ASSISTANT SECRETARIES. There may be such number of Assistant 
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Secretaries as from time to time the Members may fix, and such persons shall
perform such functions as from time to time may be assigned to them. No 
Assistant Secretary shall have the power or authority to collect, account for,
or pay over any tax imposed by any federal, state or city government.

     10.  ASSISTANT TREASURERS. There may be such number of Assistant Treasurers
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as from time to time the Members may fix, and such persons shall perform such
functions as from time to time may be assigned to them. No Assistant Treasurer
shall have the power or authority to collect, account for, or pay over any tax 
imposed by any federal, state or city government.

     11.  REMOVAL. Any officer elected or appointed by the Members may be 
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removed by the Members whenever in its judgement the best interests of the 
Company would be served thereby, but such removal shall be without prejudice to
the contract rights, if any, of the person so removed. Election of an officer 
shall not of itself create contract rights.


                                   ARTICLE V

                                MEMBER LIABILITY             
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     No Member shall be personally liable to the Company or to its members
except to the extent that such limitation of liability is prohibited by the
provisions of Texas law, and except for Member liability resulting from (a) any
breach of the Member's duty of loyalty to the Company or to its members; (b)
acts or omissions which are not in good faith or which involve intentional
misconduct or a knowing violation of law; (c) any transaction from which the
Member derived an improper personal benefit.


                                  ARTICLE VI

                                INDEMNIFICATION
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     1.   POWER TO INDEMNIFY. The Company may indemnify a Member, officer, 
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employee or agent who was or is a party or is threatened to be made a party
to any threatened, pending or completed action, suit or proceeding, whether
civil, criminal, administrative, or investigative, if he or she acted, or failed
to act, in good faith and in a manner he or she reasonably believed and, with
respect to any criminal action or proceeding, had no reasonable cause to believe
his or her conduct was unlawful. In an action not by or in the right of the
Company, such indemnification may include expenses, attorney fees, judgments,
fines and amounts paid in settlement actually and reasonably incurred. In an
action by or in the right of the Company, such indemnification may include
expenses, attorney fees and amounts paid in settlement actually and reasonably
incurred, but shall not include judgments and fines.

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     2.   LIMITS ON INDEMNIFICATION. No person shall be indemnified if he or she
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has been adjudge to be liable to the Company, unless otherwise ordered by the 
court. The Company may refuse indemnification to any person who unreasonably 
refuses to permit the Company, at its own expense and through counsel of its 
own choosing, to defend him or her in the action.

     3.   DECISION-MAKING. A decision to indemnify a person shall be made by one
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of the following: a majority vote of a quorum consisting of disinterested 
Members; if such quorum is not obtainable, a written opinion of independent 
legal counsel appointed by a majority of the disinterested Members; if there are
not disinterested Members, the court or other body before which the action was 
brought, or any court of competent jurisdiction.

                                  ARTICLE VII

                        REPEAL, ALTERATION OR AMENDMENT
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     The Articles of Organization, and Regulations may be repealed, altered, or 
amended only by a two-thirds (2/3) vote of the Members.

                                 ARTICLE VIII

                        CERTIFICATES OF OWNERSHIP AND 
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                                THEIR TRANSFER
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     1.   CERTIFICATES OF OWNERSHIP. Certificates representing ownership 
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interest in the Company shall be signed by the president or any vice president 
and by the secretary or an assistant secretary, treasurer or assistant 
treasurer of the Company. If both the signatures of the officers be by 
facsimile, the certificate shall be manually signed by or on behalf of a duly 
authorized transfer agent or clerk. Each certificate shall be consecutively 
numbered or otherwise identified, and shall also state the name of the person to
whom issued, the ownership interest, the date of issue, that the Company is 
organized under Texas law, and any express terms represented by such 
certificate.

     The name and address of each member, ownership interest, and the date on 
which the certificates were issued shall be entered on the books of the Company.
The person in whose name the ownership interests stand on the books of the 
Company shall be deemed the owner thereof for all purposes with regard to the 
Company.

     2.   LOST CERTIFICATES. If a certificate has allegedly been lost or 
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destroyed, the Members may in their discretion, except as may be required by
law, direct that a new certificate be issued upon such indemnification and other
reasonable requirements as it may impose.

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     3.   TRANSFERS OF CERTIFICATE.  Transfers of Certificates of Ownership in 
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the Company shall be recorded on the books of the Company and, except in the
case of a lost or destroyed certificate, shall be made on surrender for
cancellation of the certificate for such ownership. A certificate presented for
transfer must be duly endorsed and accompanied by proper guaranty of signature
and other appropriate assurances that the endorsement is effective.


                           CERTIFICATE OF SECRETARY
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     I hereby certify that the foregoing copy of the Regulations is a true and 
correct copy of the Regulations of the Company as the same were adopted at the 
first meeting of the Members.


Dated:  7/28/95                             /s/ Martin Fox              
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                                            SECRETARY
                                            
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