Caveolin-1 and Vascular Dysfunction

Caveolin-1 and Vascular Dysfunction

Thank you for your interest in the investigators Blood Pressure Research Study. The National
Institutes of Health are sponsoring us to investigate why patients develop high blood
pressure, atherosclerosis (hardening of the arteries), and heart disease. There are two parts
of the investigators research program. The first part is a screening visit. At this visit you
will be given a brief physical exam and will be asked questions concerning your medical
history. During the same visit you will have your blood drawn for routine screening and
genetic testing. You will also be asked to collect a urine sample for routine screening.

If the doctor finds that you are a healthy candidate you will be invited to participate in
the second part of the study. During Phase II, the investigators will perform physiological
tests after you are placed on a low salt diet and again after you are placed on a higher salt
diet. If you are on blood pressure medication, it may be necessary to discontinue taking your
present medication for up to three months before beginning the study. Patients discontinuing
their current blood pressure medication may be placed on a different blood pressure
medication during this 'washout' period if necessary to maintain blood pressure at pre-study
levels.

Once your blood pressure medications are discontinued, you will be closely monitored. If you
do not own a home blood pressure monitor, the investigators will provide one for you to use
during the study so that you can keep a daily record of your blood pressure readings. The
investigators will ask you to call us every three days to report your blood pressure
readings. After you have stopped taking your medication, dieticians at the hospital will make
you low salt meals to eat at home for about seven days. On the last day of the low salt diet,
you will be asked to begin a 24-hour urine collection that you will bring with you when you
are admitted to the hospital that evening. That morning, you will be required to come to the
Center for Clinical Investigations (CCI) at Brigham and Women's Hospital for a one-hour test
to check if your body is in the correct salt balance.

You will return that evening to the CCI where you will be admitted for your study that will
occur the next morning. On the morning of your low salt study, the investigators will collect
some blood samples. The investigators will also take ultrasound pictures of your heart to see
how salt and hormones affect the way your heart and blood vessels functions. These tests will
last approximately 5 hours and you will be discharged around 2:00 PM. For the next 5-7 days,
you will be placed on a high salt diet. During this diet period, you will eat all your own
food, but the investigators will give you some supplements to add to your meals. After 5-7
days on your high salt diet, on the morning of your second admission to the hospital, you
will be asked to begin a final 24-hour urine collection. That morning, you will again be
required to come to the CCI for a blood test, and you will return later that evening to the
inpatient CCI where you will be admitted for your final overnight study. The same study that
was done for the low salt diet will be repeated for the high salt study. You will be
discharged at around 2:00 p.m. These studies will help to determine if you are
salt-sensitive. In addition, the investigators hope to learn more about the hormones that
regulate your blood pressure and the genes responsible for regulating those hormones.

You will have the option to spend a second night in the CCI after each diet phase in order to
participate in an optional study of the blood vessels in the arm. This study also uses an
ultrasound machine. It will last about 2 hours in the morning.

You will be placed back on your initial blood pressure medication (if you are on any) and
returned to your regular physician for care. The investigators can also provide clinically
relevant information to you.