[The effects of Carvedilol, a beta-blocker, in experimental ischemia-reperfusion kidney injury]. / Studium úcinku beta-blokátoru Carvedilolu pri ischemicko-reperfuzním poskození ledviny v experimentu.

Carvedilol is a recently introduced drug with multiple action with a non-selective beta-antiadrenergic and selective alpha1-antiadrenergic action used for treatment of mild to medium severe hypertension. The authors investigated in their experiments the protective effect of carvedilol under conditions of ischaemia-reperfusion of the kidney in the laboratory rat. The animals were divided into four groups 1. the control group was fed a diet without carvedilol for a period of two weeks. Groups 2, 3 and 4 were fed for two weeks a diet containing carvedilol, 1-3-10 mg/kg/day resp. After completed medication in all animals ischaemia of the kidney was induced (60 min.) with subsequent reperfusion (10 min.) Then the animals were sacrificed, the kidney was removed for histopathological examination, in blood the malondialdehyde (MDA) level was assessed. The conclusions of the investigation indicate a marked protective effect of the administered preparation. Carvedilol prevents the disintegration of tubular epithelia, pycnosis of the nuclei, and reduced the development of oedematous changes. These findings correlate with MDA levels.

[Endothelial cells in tumors of the rectum and large intestine]. / Výskyt endoteliálních bunek pri nádorech konecníku a tlustého streva.

In 40 controls and 102 patients with tumours of the rectum and large intestine the number of circulating anuclear cell residues of endothelial cells was investigated. The number of these endothelia in the blood of patients was significantly higher (p < 0.001) than in healthy subjects. After successful surgery of the tumour and subsequent chemotherapy the number of endothelia in venous blood reached normal levels with in 1-2 months. Conversely in patients where despite surgery secondaries were detected in other organs, the number of endothelia remained elevated.

[The significance of circulating endothelial cells in type 2 diabetes]. / Význam endotelémie u diabetu 2. typu.

The authors examined in 134 type 2 diabetics under the age of 60 years (mean age 54.5 years) the number of circulating endothelia. The results were compared with the number of circulating endothelia in 12 type 1 diabetics who were in a compensated state. The number of circulating endothelial increased with the degree of metabolic decompensation, the limital value of glycosylated haemoglobin (HbA1c) was 12%. In patients with a lower HbA1c value the number of circulating endothelia was still at the upper range of normal values. The highest values were recorded in diabetics with ketosis. The elevated number of circulating endothelia does not depend on the duration of diabetes, on the method of treatment or the patient's age. The finding of an elevated number of circulating endothelia correlates also with a higher cholesterol and triacylglycerol level. The authors consider the raised number of circulating endothelia a marker of endothelial damage and thread of the development of macroangiopathy.

[The occurrence of endothelial cells in the blood in deep venous inflammation]. / Výskyt endoteliálních bunëk v krvi pri hlubokém zánetu zil.

The number of anuclear residues of endothelial cells in the blood stream was investigated in 22 patients suffering from deep phlebitis and no other disease. The level of endothelaemia in these patients was in all instances higher than in 24 healthy subjects. Assessment of the endothelaemia in patients with deep phlebitis makes more accurate assessment of the diagnosis and the follow-up of regression of the disease possible.

Regional differences of cardiovascular effects of diltiazem in the rat.

The dose-response relations of the central and peripheral effects of diltiazem were studied in 26 anaesthetized rats. Measured were the heart rate (HR), atrioventricular conduction time (PR), mean arterial blood pressure (BP), carotid and renal blood flow (Fc, Fr) and the corresponding relative regional resistance (RRc, RRr). The effects were evaluated by their maxima regularly reached 15-20 s after the i.v. bolus administration. The minimum dose which produced a significant HR decrease and PR prolongation were 0.4 and 2.0 mg/kg, respectively. In the mg/kg dose range a transient second degree AV block was regularly recorded. The lethal dose (cardiac arrest) was 20 mg/kg. BP significantly already decreased after 4 micrograms/kg. The dose-dependent decrease of Fr matched the hypotensive effect in the whole range due to unchanged RRr. In contrast Fc invariably increased at lower doses reflecting the RRc decay. Only in the mg/kg dose range Fc decreased in accord with BP since RRc dropped to a constant value (50% of control) with each administration. The peripheral reactions were significantly augmented in rats with renovascular hypertension. It is concluded that, in this model, the peripheral effects of diltiazem evidently surpass the central ones. The regional difference between the inert renal and responsive carotid vasculature might be due to a different mode of regulation of the respective vascular tone, hypothetically reflecting different density of membrane, potential-dependent Ca2+ channels.

The effect of prostaglandins E2 and F2 alpha on carotid blood flow in rats with renovascular hypertension.

The effect of i.v. bolus administration of PGE2 and PGF2 alpha on carotid blood flow (Q) and mean arterial blood pressure (MAP) was recorded in 21 anaesthetized normotensive control (N) and 12 rats with 1K1C renovascular hypertension (RH). From the measured parameters the regional vascular impedance (PVI) and the change in blood volume were calculated. In normotensive animals both PGs elicited a dose-dependent initial fast increase of Q (threshold dose 0.4 ng/kg) and a decrease of MAP and PVI (threshold dose 0.4 micrograms/kg). Subsequently, Q decreased below the initial level. MAP and PVI remained depressed after E2 but increased after F2 alpha. The time course of the Q and MAP responses was analyzed in more detail at a standard dose 4 micrograms/kg. The average time to peak of the first phase was 12 s and of the second approximately 80 s. The initial levels of Q and MAP were reestablished within 3 to 4 minutes. The total volume of carotid blood flow obtained by planimetric integration was unaltered after F2 alpha but depressed after E2. In hypertensive animals both phases of the response to E2 were significantly retarded and the Q response was nearly abolished. On the other hand, the time course of the reaction to F2 alpha was unchanged but the magnitude of the second pressoric phase was reduced. Thus, the capacity of the carotid vascular bed to dilate remains the same in RH while the ability to constrict is limited. It is concluded that the response of MAP and Q to both PGs are relatively independent.(ABSTRACT TRUNCATED AT 250 WORDS)