title: Coronary vasoconstrictor responses are attenuated in young women as compared with age-matched men.
abstract: Recent work in humans suggests coronary vasoconstriction occurs with static handgrip with a time course that suggests a sympathetic constrictor mechanism. These findings are consistent with animal studies that suggest this effect helps maintain transmural myocardial perfusion. It is known that oestrogen can attenuate sympathetic responsiveness, however it is not known if sympathetic constrictor responses vary in men and women. To examine this issue we studied young men (n = 12; 28 ± 1 years) and women (n = 14; 30 ± 1 years). Coronary blood flow velocity (CBV; Duplex Ultrasound), heart rate (ECG) and blood pressure (BP; Finapres) were measured during static handgrip (20 s) at 10% and 70% of maximum voluntary contraction. Measurements were also obtained during graded lower body negative pressure (LBNP; activates baroreflex-mediated sympathetic system) and the cold pressor test (CPT; a non-specific sympathetic stimulus). A coronary vascular resistance index (CVR) was calculated as diastolic BP/CBV. Increases in CVR with handgrip were greater in men vs. women (1.25 ± 0.49 vs. 0.26 ± 0.38 units; P < 0.04) and CBV tended to fall in men but not in women (−0.9 ± 0.9 vs. 1.7 ± 0.8 cm s−1; P < 0.01). Changes in CBV with handgrip were linked to the myocardial oxygen consumption in women but not in men. CBV reductions were greater in men vs. women during graded LBNP (P < 0.04). Men and women had similar coronary responses to CPT (P = n.s.). We conclude that coronary vasoconstrictor tone is greater in men than women during static handgrip and LBNP.
authors.affiliation: Penn State Heart & Vascular Institute, Penn State College of Medicine, The Milton S. Hershey Medical Center, Hershey, PA 17033, USA.
authors.forename: Afsana
authors.initials: A
authors.lastname: Momen
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Gao
authors.forename: Abigail
authors.initials: A
authors.lastname: Cohen
authors.forename: Tamreen
authors.initials: T
authors.lastname: Khan
authors.forename: Urs A
authors.initials: UA
authors.lastname: Leuenberger
authors.forename: Lawrence I
authors.initials: LI
authors.lastname: Sinoway
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D017704:Baroreflex / Q000502:physiology; D001783:Blood Flow Velocity / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D003331:Coronary Vessels / Q000502:physiology*; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D012737:Sex Factors; D014661:Vasoconstriction / Q000502:physiology*
references.citation: Eur Heart J. 1990 Apr;11 Suppl B:43-52
references.pmid: 2364955
references.citation: J Am Coll Cardiol. 2009 Oct 20;54(17):1561-75
references.pmid: 19833255
references.citation: J Appl Physiol (1985). 1988 Jun;64(6):2287-93
references.pmid: 2900233
references.citation: J Appl Physiol (1985). 2003 Oct;95(4):1418-24
references.pmid: 12819220
references.citation: Heart Fail. 1990 Jan-Feb;6(1):33-41
references.pmid: 11539207
references.citation: Circ Res. 1982 Feb;50(2):273-86
references.pmid: 6120048
references.citation: Am J Physiol Heart Circ Physiol. 2002 Nov;283(5):H2038-44
references.pmid: 12384483
references.citation: Am J Physiol Regul Integr Comp Physiol. 2005 Jul;289(1):R109-16
references.pmid: 15761188
references.citation: Am J Physiol Heart Circ Physiol. 2002 Feb;282(2):H508-15
references.pmid: 11788398
references.citation: J Am Coll Cardiol. 1998 Nov;32(5):1251-9
references.pmid: 9809933
references.citation: Circulation. 1985 Mar;71(3):620-5
references.pmid: 3971531
references.citation: Circ Res. 1981 Jun;48(6 Pt 2):I118-30
references.pmid: 7226455
references.citation: J Appl Physiol (1985). 1999 Feb;86(2):767-72
references.pmid: 9931219
references.citation: Circulation. 1992 May;85(5):1899-911
references.pmid: 1572046
references.citation: J Korean Med Sci. 2000 Apr;15(2):139-45
references.pmid: 10803688
references.citation: Circulation. 2008 Mar 25;117(12):1526-36
references.pmid: 18347213
references.citation: Circ Res. 1992 Jul;71(1):188-200
references.pmid: 1318795
references.citation: Am J Physiol Heart Circ Physiol. 2010 Feb;298(2):H524-9
references.pmid: 19940080
references.citation: J Appl Physiol (1985). 1998 Dec;85(6):2075-81
references.pmid: 9843528
references.citation: Circulation. 1998 Apr 28;97(16):1557-62
references.pmid: 9593560
references.citation: Clin Sci (Lond). 2004 Nov;107(5):449-60
references.pmid: 15362973
references.citation: Circ Res. 1986 Jan;58(1):68-82
references.pmid: 3002658
references.citation: Circ Res. 1988 Feb;62(2):286-98
references.pmid: 2827910
references.citation: Circulation. 2000 Jul 25;102(4):445-51
references.pmid: 10908218
references.citation: Am J Cardiol. 1980 Apr;45(4):782-90
references.pmid: 7361669
references.citation: J Clin Endocrinol Metab. 2001 Jan;86(1):344-8
references.pmid: 11232022
references.citation: Basic Res Cardiol. 1995 Jan-Feb;90(1):73-83
references.pmid: 7779067
references.citation: Circ Res. 1988 Feb;62(2):216-25
references.pmid: 2827908
references.citation: Circulation. 1991 Nov;84(5):2034-9
references.pmid: 1934378
references.citation: Am J Cardiol. 2003 Feb 15;91(4):412-7
references.pmid: 12586254
references.citation: J Appl Physiol. 1972 Apr;32(4):516-22
references.pmid: 5026501
references.citation: Am J Physiol. 1994 Aug;267(2 Pt 2):H821-7
references.pmid: 8067438
references.citation: Circ Res. 1993 Nov;73(5):869-86
references.pmid: 8403257
references.citation: J Appl Physiol (1985). 2002 Apr;92(4):1635-41
references.pmid: 11896031
references.citation: Circ Res. 1989 Dec;65(6):1688-97
references.pmid: 2555079
references.citation: Circulation. 2000 Dec 12;102(24):2938-44
references.pmid: 11113043
references.citation: Lancet. 1993 May 15;341(8855):1264-5
references.pmid: 8098404
references.citation: J Am Coll Cardiol. 1999 Oct;34(4):1193-200
references.pmid: 10520812
references.citation: Am J Physiol Heart Circ Physiol. 2001 Nov;281(5):H2028-35
references.pmid: 11668064
references.citation: Am J Physiol. 1987 Aug;253(2 Pt 2):H388-93
references.pmid: 2887122
references.citation: Hypertension. 1987 May;9(5):429-36
references.pmid: 3570420
references.citation: Am J Physiol Heart Circ Physiol. 2009 Jan;296(1):H186-94
references.pmid: 19028800
references.citation: J Appl Physiol Respir Environ Exerc Physiol. 1983 Apr;54(4):1057-62
references.pmid: 6853281
references.citation: Am J Physiol Heart Circ Physiol. 2009 Mar;296(3):H854-61
references.pmid: 19168724
references.citation: Coron Artery Dis. 1995 May;6(5):417-22
references.pmid: 7655729
references.citation: Circulation. 2001 Jun 19;103(24):2903-8
references.pmid: 11413078
references.citation: Circulation. 2003 Jul 29;108(4):457-63
references.pmid: 12860902
references.citation: N Engl J Med. 1999 Jun 10;340(23):1801-11
references.pmid: 10362825
references.citation: Circulation. 1991 Nov;84(5):2108-22
references.pmid: 1682067
references.citation: Am J Physiol Heart Circ Physiol. 2009 Apr;296(4):H1157-63
references.pmid: 19234088
references.citation: Circulation. 1994 Oct;90(4):1964-8
references.pmid: 7923686
references.citation: Prog Cardiovasc Dis. 1987 Nov-Dec;30(3):211-34
references.pmid: 2823312
references.citation: Circulation. 2000 Dec 12;102(24):2930-7
references.pmid: 11113042