Selections of Subjects With Important Changes in Their Cardiac Repolarization Parameters for the Procurement of Skin and Blood Samples

Inclusion Criteria: * 18 to 40 years of age * Caucasian origin * BMI 19 to 29 kg/m² * Informed Consent obtained * National Health Security Number * Eligible for Phase I as mentioned in the national registry of healthy volunteers * For woman: use of an effective contraceptive method Non Inclusion Criteria: * Asthma * Heart Rate \< 50 bpm * Hypotension with systolic blood pressure\< 100 mm Hg. * atrioventricular block (PR interval \> 200 ms) * Known Chronic illness (hepatic, renal or cardiac impairment, etc..) * Raynaud's phenomenon * Drug known to prolong QT (http://www.azcert.org/medical-pros/drug-lists/drug-lists.cfm) in the last 7 days. * All chronic treatments are forbidden exceptive : oral contraceptives, paracetamol, vitamins and comfort treatment that do not prolong the QT * Known family or individual past history of QT prolongation or unexplained syncope * (QTcF) \> 450 ms * QRS interval non assessable on ECG at rest or bundle-branch block, QRS \> 100 ms * Allergy to macrolide type antibiotics * Known allergy to sotalol or lidocaine * Positive blood pregnancy test (Inclusion visit) * Known abnormal haemostasis * Kaliemia\< 3.5 mmol/L * Magnesemia\< 0,7 mmol/L * Under exclusion period or participating to another clinical trial on a new medicinal product * Creatinin clearance \< 80 ml/min (Cockroft and Gault formula) * AST-ALT \>3x upper normal limit