Effect of oral contraceptives on endothelial function in the peripheral microcirculation of healthy women.
OBJECTIVE
We assessed whether third-generation oral contraceptive (OC) treatment (30 microg ethinylestradiol + 75 microg gestodene daily) could affect the endothelial function of healthy women.


METHODS
In 20 young healthy women (HW) and 10 hypercholesterolemic women (CW) we assessed forearm blood flow (strain-gauge plethysmography) changes induced by the intrabrachial infusion of acetylcholine (ACH) (0.15-15 microg/100 ml forearm tissue/min) and sodium nitroprusside (SNP) (1-4 microg/100 ml forearm tissue/min). ACH was repeated during the nitric oxide synthase inhibitor intra-arterial NG-monomethyl-L-arginine (L-NMMA) (100 microg/100 ml forearm tissue/min) or the antioxidant vitamin C (8 mg/100 ml forearm tissue/min). HW repeated the protocol after 6-month OC (n = 10) or placebo (n = 10) treatment.


RESULTS
In HW the maximal vasodilation to ACH, similar between placebo and OC subgroups, was significantly reduced in CW (P < 0.01). Vasodilation to ACH was blunted (P < 0.01) by L-NMMA and unaffected by vitamin C, in both OC and placebo groups. In CW the vasodilation to ACH, not modified by L-NMMA, was improved by vitamin C (P < 0.01). OC treatment raised (P < 0.01) plasma total and low-density lipoprotein cholesterol, and values were similar to those shown by CW. Both OC and placebo intake did not change the response to ACH and the modulation induced by L-NMMA or vitamin C. Vasodilation to SNP was similar in all groups.


CONCLUSIONS
In HW 6-month treatment with third-generation OC, although associated with an abnormal lipid profile, does not adversely affect endothelium-dependent vasodilation. This neutral effect could be the balance between a deleterious effect of hypercholesterolemia and a protective effect of OC on endothelial function.
Virdis
Agostino
A
Department of Internal Medicine, University of Pisa, Italy. a.virdis@med.unipi.it
Pinto
Stefania
S
Versari
Daniele
D
Salvetti
Guido
G
Bernini
Gianpaolo
G
Fruzzetti
Franca
F
Genazzani
Andrea R
AR
Taddei
Stefano
S
Salvetti
Antonio
A
D000109:Acetylcholine / Q000008:administration & dosage; D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage; D001205:Ascorbic Acid / Q000008:administration & dosage; D015415:Biomarkers / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood / Q000187:drug effects; D003276:Contraceptives, Oral / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000008:administration & dosage; D005260:Female; D005542:Forearm / Q000098:blood supply*; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000503:physiopathology; D008833:Microcirculation / Q000187:drug effects; D009599:Nitroprusside / Q000008:administration & dosage; D012016:Reference Values; D012039:Regional Blood Flow / Q000187:drug effects; D014280:Triglycerides / Q000097:blood; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage; D016387:Women's Health; D019323:omega-N-Methylarginine / Q000008:administration & dosage
D000975:Antioxidants; D015415:Biomarkers; D008078:Cholesterol, LDL; D003276:Contraceptives, Oral; D004791:Enzyme Inhibitors; D014280:Triglycerides; D014665:Vasodilator Agents; D009599:Nitroprusside; D019323:omega-N-Methylarginine; D000109:Acetylcholine; D001205:Ascorbic Acid