![]() |
|
|
WM Armstead, R Mirro, DW Busija and CW Leffler
Department of Physiology and Biophysics, University of Tennessee, Memphis.
The present study was designed to test the hypothesis that prostanoids play a permissive role in acetylcholine-induced cerebral constriction. Pial arterioles of newborn pigs were observed using a closed cranial window. Pial arteriolar constriction induced by topical acetylcholine (10(-5) M) was blocked by indomethacin (5 mg/kg i.v.), but was restored when acetylcholine was coadministered with topical prostaglandin (PG) F2 alpha (1 ng/ml), U46619 (1 ng/ml) or PGH2 (100 ng/ml). The restored acetylcholine response was blocked by topical pirenzepine (10(-3) M), a muscarinic-1 antagonist. Constriction and ability of all three prostanoids to restore acetylcholine-induced constriction was blocked by SQ 29,548 (10(-4) M), a purported thromboxane A2/PGH2 receptor antagonist. Subthreshold concentrations of U46619 and PGF2 alpha (0.1 ng/ml) restored acetylcholine-induced constriction, whereas threshold and subthreshold concentrations of PGE2, platelet-activating factor and norepinephrine had no effect. Therefore, activation of the thromboxane A2/PGH2 receptor appears to be necessary for acetylcholine-induced constriction to occur. Thus, prostanoids appear to play a permissive role in acetylcholine-induced pial arteriolar constriction in newborn pigs.
This article has been cited by other articles:
![]() |
R. J. Gonzales, A. A. Ghaffari, S. P. Duckles, and D. N. Krause Testosterone treatment increases thromboxane function in rat cerebral arteries Am J Physiol Heart Circ Physiol, August 1, 2005; 289(2): H578 - H585. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. P. Willis and C. W. Leffler Endothelial NO and prostanoid involvement in newborn and juvenile pig pial arteriolar vasomotor responses Am J Physiol Heart Circ Physiol, December 1, 2001; 281(6): H2366 - H2377. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. J. Pearce, S. P. Duckles, and J. Buchholz Effects of maturation on adrenergic neurotransmission in ovine cerebral arteries Am J Physiol Regulatory Integrative Comp Physiol, October 1, 1999; 277(4): R931 - R937. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. P. Willis and C. W. Leffler NO and prostanoids: age dependence of hypercapniaand histamine-induced dilations of pig pial arterioles Am J Physiol Heart Circ Physiol, July 1, 1999; 277(1): H299 - H307. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Zucker and C. W. Leffler PTX-sensitive G proteins and permissive action of prostacyclin in newborn pig cerebral circulation Am J Physiol Heart Circ Physiol, July 1, 1998; 275(1): H259 - H263. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Toda, M. Toda, K. Ayajiki, and T. Okamura Cholinergic nerve function in monkey ciliary arteries innervated by nitroxidergic nerve Am J Physiol Heart Circ Physiol, May 1, 1998; 274(5): H1582 - H1589. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. W. Leffler, A. L. Fedinec, and M. Shibata Prostacyclin Receptor Activation and Pial Arteriolar Dilation After Endothelial Injury in Piglets Stroke, November 1, 1995; 26(11): 2103 - 2111. [Abstract] [Full Text] |
||||