A role for cyclooxygenase in aging-related changes of beta-adrenoceptor-mediated relaxation in rat aortas.

beta-Adrenoceptor-mediated vasorelaxation decreases with age in various vascular beds. The present study investigated the roles of cyclooxygenase (COX) on beta-adrenoceptor vasorelaxation by isoprenaline in 8- and 54-week-old rat aortas. The vasorelaxation responses by isoprenaline (0.

Approaches for introducing peptides into intact and functional arteriolar smooth muscle: manipulation of protein kinase-based signalling.

1. An exact understanding of signal transduction pathways within intact and functional arteriolar smooth muscle is made difficult by limited access to the intracellular environment due to the cell membrane. The aim of the present studies was to determine the feasibility of using polycationic lipids and reverse permeabilization for the introduction of peptide inhibitors into smooth muscle cells of the intact arteriolar wall.

Intracoronary basic fibroblast growth factor enhances myocardial collateral perfusion in dogs.

Objective: In preparation for clinical trials of basic fibroblast growth factor (bFGF) to treat ischemic heart disease, we sought to identify a clinically feasible method of bFGF administration.

Background: Basic FGF has been shown to promote collateral development after experimentally induced coronary occlusion; however, methods of bFGF delivery that have been shown to be effective in previous investigations would not be practical for clinical use.

Methods: Four randomized, blinded, controlled investigations were conducted independently and sequentially in an established canine model.

Myogenic reactivity of rat epineurial arterioles: potential role in local vasoregulatory events.

Local control of neural blood flow is considered to reside in innervation of epineurial and endoneurial arterioles rather than in intrinsic autoregulatory mechanisms. With the use of an isolated vessel preparation and an in vivo approach, the present studies examined intrinsic vasomotor responsiveness of epineurial arterioles. Segments of epineurial arterioles, cannulated on glass micropipettes (40 micrometers) and pressurized in the absence of intraluminal flow, showed sustained pressure-dependent (30-90 mmHg) vasoconstriction and acute myogenic reactivity.

Differential activation of adrenoceptor subtypes by noradrenaline applied from the intimal or adventitial surfaces of rat isolated tail artery.

1. The vasoconstrictor effects of noradrenaline applied to the intimal and adventitial surfaces of perfused segments of rat tail artery in the presence and absence of endothelium were studied. 2.