摘要:

In previous experiments, injury-induced atherosclerosis has been shown to be associated with the development of fatty streaks. The findings suggested that fatty streaks might represent a stage in healing of intimal injury evolving to fibrous plaques, free of lipid. The present experiment was designed to study the incidence and evolution of these lesions during a 2-week period of lesion retrogression following removal of a catheter placed in the aorta for 1 week. The findings indicate that as fat-containing lesions, either of the thromboatherosclerotic or fatty streak varieties, decreased, the amount of nonlipid-containing fibrous lesions increased.

ISSN:1018-1172    

DOI:10.1159/000158128

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Prostaglandins appear to play an important role in a number of reproductive processes. The present study was designed to determine if the vasodilator action of prostaglandins of the A and E series on uterine vascular smooth muscle was mediated via a receptor and if PGF2α could compete for this same receptor. The data demonstrate that PGF2α which by itself has no uterine vascular effect, can produce a parallel shift in the dose-response curves for certain vasodilator prostaglandins. This action, which suggests competitive antagonism, may well play a role in regulating blood flow in the nonpregnant uteru

ISSN:1018-1172    

DOI:10.1159/000158129

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Norepinephrine (NE) and epinephrine (E) concentrations were determined fluorometrically as an index of functional adrenergic innervation in small mesenteric arteries, veins, and superior mesenteric arteries of dogs and rats subjected to a period of prolonged hemorrhage at a constant mean arterial pressure of 35 mm Hg. In nonhemorrhaged animals, highest catecholamine concentrations were found in the small principal arteries, next highest in the small veins, and least in superior mesenteric arteries. A significant decrease occurred in the NE and E concentrations of all three vessel types in the dog during the decompensatory phase of the hypotensive stress (defined as the hypotensive period beyond the time at which maximum bleedout volume occurred). In the rat significant decreases were detectable only in the NE concentrations of the small arteries and veins during this phase. It is concluded that the increase in neurogenic vascular tone accompanying severe hemorrhagic stress is lost simultaneously on the arterial and venous sides of compensatory vascular beds. Such loss is closely related to transmitter depletion at the adrenergic neuromuscular junction and, if allowed to continue uncorrected, can contribute significantly to irreversible cardiovascular collapse.

ISSN:1018-1172    

DOI:10.1159/000158130

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

When assayed on homogenates of the rabbit ear artery up to 192 h after sympathetic denervation, the activity of monoamine oxidase (MAO) showed a small but significant decrease (maximum 9%). The activity of catechol-O-methyl transferase (COMT) appeared unchanged, although it is possible that the small and variable nature of this enzyme activity compared with that of MAO may have masked a comparable effect of denervation. The maximum decreases in noradrenaline (NA) and adenosine triphosphate (ATP) contents were >90% at 48 h, and 32% at 96 h after denervation. These results confirm the presence of neuronal as well as extraneuronal MAO, and also the presence of extraneuronal COMT in this artery. The decline in ATP contents after denervation suggest that part of the ATP is neuronal. However, the estimated ratio of NA to neuronal ATP is far in excess of that reported for isolated noradrenaline storage vesicles, suggesting that the major portion of the neuronal ATP was not present in these vesicles.

ISSN:1018-1172    

DOI:10.1159/000158131

出版商:S. Karger AG    

年代:1977

数据来源: Karger

ISSN:1018-1172    

DOI:10.1159/000158132

出版商:S. Karger AG    

年代:1977

数据来源: Karger