A study of the phasic response of arterioles of the guinea pig small intestine to prolonged exposure to norepinephrine.

Microvascular Research
T O Neild, N Kotecha

Abstract

Arterioles of the guinea pig small intestine constricted in response to norepinephrine, but the constriction was not maintained. The duration of constriction was reduced after pretreatment by theophylline, 3-isobutyl-1-methyl-xanthine, bromo-cAMP, or bromo-cGMP, suggesting that the relaxation was related to an increase in cyclic nucleotide levels in the cell. Forskolin also reduced the duration of constriction, suggesting the involvement of cAMP. The duration of constriction was not affected by propranolol or isoprenaline, indicating no involvement of beta adrenoceptors. A scheme to explain these observations, in which alpha 1-adrenoceptor activation stimulates adenylate cyclase, leading to a rise in cAMP and an increased rate of intracellular calcium sequestration is proposed. The resulting fall in intracellular calcium leads to repolarization and relaxation.

References

May 1, 1977·British Journal of Pharmacology·J C DoxeyJ M Walker
Mar 1, 1975·Metabolism: Clinical and Experimental·G SchultzJ G Hardman
Dec 1, 1977·The Journal of Physiology·G D Hirst
Jan 31, 1979·Naunyn-Schmiedeberg's Archives of Pharmacology·K D SchultzG Schultz
Mar 22, 1988·European Journal of Pharmacology·G C GraceG J Dusting
Mar 1, 1986·Journal of Autonomic Pharmacology·J A Leedham, J N Pennefather
May 1, 1987·The Journal of Physiology·T O Neild
Nov 1, 1971·The American Journal of Physiology·G Ross
Dec 1, 1983·Pflügers Archiv : European journal of physiology·K D Meisheri, J C Ruegg
Jul 1, 1983·Microvascular Research·L C MaxwellG L Riedel

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Citations

Jan 1, 1990·General Pharmacology·G P Morley, T O Neild
Feb 12, 1998·The American Journal of Physiology·J Xia, B R Duling

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