Comparative effectiveness of propafenone and aksaritmin for conversion of paroxysmal atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Aksaritmin (the sum of nine deterpenoid alkaloids, including lappaconitini hydrobromidum) is an antiarrhythmic drug (conditionally belongs to the I C class) which is extracted from the roots and rhizomes of local plant - Aconitum septentrionale (tablet 25 mg).

Purpose

Evaluation of comparative effectiveness of propafenone (Pr) and aksaritmin (Aks) for conversion of atrial fibrillation (AF) in patients without/minimal structural heart disease (ejection fraction is more than 50%).

Materials and methods

The study included 60 patients (31 men), mean age - 55.3±11.9 y.o. The inclusion criteria for patients in the study were: hemodynamically stable symptomatic paroxysmal AF (mean duration–16.3±9.1 hours). On the day of admission, all patients underwent a test of the necessary biochemical blood parameters, electrocardiography, 24-hour ECG monitoring, transthoracic echocardiography. The patients were divided into two groups (they did not differ in the main clinical and anamnestic characteristics): 1-group (n=30), Pr was prescribed in dose 450-600 mg per os; 2-group (n=30), Aks was prescribed in dose 50 mg (in combination with beta-blockers (60%) in cases of tachysystole (≥ 140 b.p.m.)) per os. Statistical analysis was carried out by the STATISTICA 13.

Results

The main causes of AF in group 1 and group 2: hypertension - 17 (56.7%) and 16 (53.3%), chronic persistent myocarditis - 11 (36.7%) and 12 (40%), idiopathic AF - 2 (6.7%) and 2 (6.7%) patients, respectively. The anamnesis of AF averaged 17.3±3.8 months in gr 1 and 18.2±4.7 months in gr 2. Pr according to the above-described scheme ("pill in a pocket"), sinus rhythm was restored in 22 (73.3%) of 30 patients, and the mean time to restore the sinus rhythm was 4.12±3.87 hours from the start of therapy. At the same time, the effectiveness of Pr in patients with a paroxysm duration of less than 24 hours was 77.2% - in 17 patients out of 22, with a duration 24-48 hours it was 62.5% - 5 patients out of 8. Aks restored sinus rhythm in 21 (70%) out of 30 patients (χ2=0.082; p>0.05), and the mean restoring time of sinus rhythm was 4.63±4.33 hours from the start of therapy (p>0.05). At the same time, the effectiveness of Aks in patients with a paroxysm duration of less than 24 hours was 81.8% - in 18 patients out of 22 (χ2=0.140; p>0.05), with a duration of more than 24-48 hours it was 37.5%-3 patients out of 8 (χ2=1.000; p>0.05).

Conclusion

Pr and Aks practically did not differ in efficiency (73.3% and 70%, respectively) and in the time of relief (4.12±3.87 h and 4.63±4.33 h, respectively) of AF paroxysms. At the same time, Aks (including combination with beta-blockers) was more preferable for relief of AF with a duration of up to 24 hours-81.8% versus 77.2% (p>0.05), and propafenone for relief of AF with a duration of more than 24-48 hours-62.5% versus 37.5% (p>0.05). Aks is relatively new and promising drug for the treatment of patients with new onset paroxysmal AF.

PRO-INFLAMMATORY EFFECTS OF EXPERIMENTAL HYPERTHYROIDISM IN COLON OF MICE (IMMUNOHISTOCYTOCHEMICAL STUDY)

Thyroid hormones can exert responses in various immune cells affecting several inflammation-related processes. The interactions between the endocrine and immune systems have been shown to contribute to pathophysiological conditions. Aim of study - to answer the question if hyper- or/and hypothyroid state can be as provoking factor for inflammation in colon. The study was performed on 60 mature male mice of the inbred line C3H-A. On male mice was reproduced a model of experimental hyperthyroidism and hypothyroidism by oral intake of L-thyroxin and propylthyouracil, accordingly. By the 22nd week of the experiment all animals were sacrificed. The rectum was removed for histo- and immunocytochemical examination. In histological examination in hyperthyroid group the hypertrophy of the mucous membrane of the colon is detected. Simultaneously the frequency of cell mitosis is increased. Among the epithelium glands of the colon can clearly be seen apoptotic bodies. Moderate or expressed infiltration by lymphocytes and plasma cells is elucidated in mucous membrane of colon relatively to mucous membrane of colon of euthyroid group i.e. control one. In hyporthyroid group the hyportrophy of the mucous membrane of the colon was detected. The lymphocytic infiltration is not found. In immunocytochemical examination the frequency of CD20 and CD56 positive cells was significantly higher (>23%) in cytological preparation of membrane mucous of colon from hyperthyroid mice (p<0.01). Meanwhile CD20 and CD56 positive cells were detected in single cases in cytological preparation of membrane mucous of colon from hypothyroid mice. The same observation was done for healthy membrane mucous from control (euthyroid) group. It is possible that the thyroid status is one of the factors modulating the inflammation. This discussion is far from over, because it is unclear whether prolonged hyperthyroidism can actually activate pro-inflammatory reactions, which subsequently, in turn, activate carcinogenesis.

OX1R ANTAGONIST SB408124 ACTION AND EXTRAHYPOTHALAMIC CRF IN RATS AFTER PSYCHOTRAUMATIC EXPOSURE

Corticoliberin (CRF) isn't only regulates hypothalamic-pituitary-adrenal axis activity, but also functions as a neurotransmitter in extrahypothalamic brain regions like amygdala, implicated in the emotional responses to stress. The CRF system provides an input to orexin neurons and can modulate the activity of orexinergic neurons in stress response. Some data showed the role of orexin-A in extinction of aversive memory. The orexin system was shown to participate in stress-induced behavior connected with the extended amygdala structures, like central nucleus of the amygdala. The objective was to study the effects of orexin-A antagonist SB-408124 in rats after predator-induced stress using behavioral tests and its effects on CRF level in amygdala. In this study 30 male Wistar rats were used. The animals received an intranasally selective antagonist of Orexin receptor 1 type SB-408124. Posttraumatic stress disorder was modelled by single predator exposure. A group of 10-12 rats were placed in a terrarium with an indian python. 7 days after exposure to the predator, the behavior of animals was tested in the Open Field and Elevated Cross-Maze tests. Free motor activity of animals was studied in the "open field" test. To assess stress, we used the "elevated cross-maze " test. CRF concentrations in brain structures were measured by solid-phase ELISA using the Corticotropin Releasing Factor (CRF) test system. In the group of stressed rats receiving intranasally SB-408124, the time of stay in the light arm was restored, but did not reach the control values, the number of runs was restored to the control level, and the number of grooming acts increased in comparison with both the control group and the stressed animals. In the "open field" in the group of stressed rats receiving saline solution, the number of sniffs and rearing were decreased, but the number of peeks into holes was increased. In the group of stressed rats receiving SB-408124 20 µg intranasally, the number of sniffs was increased and the number of hole peeking decreased in comparison with the stressed rats receiving saline solution. The CRF level in the homogenates of amygdala in stressed rats was lower (0.44±0.07 ng/mg protein vs. 0.61±0.01 ng/mg in the control group). In the intranasal administration of SB408124 group this decrease was not recorded and the CRF level in the amygdala was 0.57±0.01 pg/mg protein. Orexin A antagonist SB-408124 reduced anxiety after psychotraumatic exposure. Predator induced acute psychotraumatic exposure decrease CRF level in the rat's amygdala. Intranasal administration of selective orexin 1 receptor antagonist SB408124 restored it closely to normal and has an anxiolytic effect on animal behaviour.

UNEQUAL HORMONAL RESPONSE OF MALE AND FEMALE C3H-A MICE TO THE THYROID AND ANTITHYROID AGENT TREATMENTS

The state of physiological functions of the whole organism, its vital activity and adaptation to various changes in the surrounding and internal environment is controlled by neurohumoral mechanisms. The main place in the implementation of those mechanisms belongs to hormones. A clinically relevant problem is currently the relationship between activity of thyroid gland and prolactin. Aim of study. - To elucidate further the relationship of thyroid-stimulating hormone, thyroxine and prolactin. The study was performed on virgin 30 mature male mice and 33 mature female mice of the inbred line C3H-A. On male and female mice was reproduced a model of experimental hyperthyroid and hypothyroid status by the administration to L-thyroxin and propylthyouracil, accordingly. The blood samples from animals were assayed for TSH, T4 (total) and prolactin. In the hyperthyroid male mice the level of T4 (total) was significantly higher as compared to the hypothyroid and control groups. No deference for the level of TSH and prolactin was found between the hyperthyroid and the hypothyroid groups. In the hypothyroid female mice the level of TSH and T4 (total) was significantly lower and the level of prolactin was significantly higher as compared to the hyperthyroid and the control groups. The male and female mice responded in different ways upon the administration to L-thyroxin and propylthyouracil on the level of TSH, T4 (total) and prolactin.

The ascertainment of multiplex schizophrenia pedigrees from Daghestan genetic isolates (Northern Caucasus, Russia)

This article describes the preliminary ascertainment of multiplex schizophrenia pedigrees from the isolated mountain region of Daghestan (Northern Caucasus, Russia). Daghestan has a population of two million people and contains 26 aboriginal ethnic groups. Many of the ethnic groups reside in remote mountain villages that can be classified as 'primary isolates'. Prolonged reproductive isolation and severe environmental conditions in the highlands have created diverse, genetically isolated ethnic populations in Daghestan. A number of the isolates in this region contain large extended multiplex schizophrenia pedigrees that are ideal for genetic analyses. During summer expeditions of 1996 and 1997, 14 separate large multiplex schizophrenia pedigrees were ascertained from 14 different mountain villages. Of the 14 kindreds, one had 50 schizophrenic cases available for ascertainment, one had 32, and another had 24. Seven of the remaining pedigrees had between 11 and 23 living cases. Within the kindreds, the number of males with chronic schizophrenia was at least twice that of females. The average age of onset of schizophrenia is 21.2 years for offspring of consanguineous marriages and 17.4 years for offspring of nonconsanguineous marriages (P = 0.033). Although the pedigrees ascertained from the remote mountain villages may not be representative of the general population, they are unique kindreds for mapping schizophrenia susceptibility genes.