Effects of some neurotransmitters and prostanoids on isolated human intracervical arteries

Human cervical tissue specimens were excised after hysterectomy at various phases of the menstrual cycle (n = 12), and small intracervical arteries were dissected free by microtechnique. Ring preparations of the vessels were prepared and mounted in organ baths, and isometric circular tension was recorded. Norepinephrine, 3 X 10(-8) to 10(-5) mol/L, produced concentration-dependent contractions, whereas 3 X 10(-7) to 10(-6) mol/L prostaglandin F2 alpha inconsistently produced weak contractions and slightly increased tension induced by 10(-5) mol/L norepinephrine. Prostaglandin I2, 10(-9) to 10(-6) mol/L, prostaglandin E2, 3 X 10(-9) to 10(-6) mol/L, vasoactive intestinal polypeptide, 10(-9) to 10(-7) mol/L, and substance P, 10(-12) to 10(-9) mol/L, induced relaxation of vessels precontracted by 10(-5) mol/L norepinephrine. It is suggested that several mechanisms for the local release of vasoactive compounds may influence cervical blood flow. Thus, sympathetic control of cervical blood flow may be modulated by peptide neurotransmitters such as vasoactive intestinal polypeptide and substance P and by local synthesis of prostaglandins E2 and I2.