Search

Objectives: The aim of the study was to investigate whether the vocal self-concept and potential vocal and related mental health problems of university teachers and academic advisers can be improved by participating in preventive voice training., Study Design and Methods: University teachers and academic advisers show an increased susceptibility to occupational risk factors related to their voice and an increased prevalence of developing a voice disorder in the course of their employment. An experimental, prospective, longitudinal study was conducted to examine whether voice training (1) improves physiological vocal function, vocal performance, vocal self-concept, and mental health of university teachers and academic advisers; (2) reduces unfavorable influencing factors at the university workplace; and (3) fewer voice problems are reported from the perspective of university teachers and academic advisers., Results: This study showed that voice training has positive influences on the voice (function and quality), voice self-concept, and well-being of university staff., Conclusions: Workplace prevention programs can help to reduce the high prevalence of voice disorders among university teachers and advisers and counteract the risk factors. They should therefore be firmly integrated into continuing education/university health management and everyday life to cope with certain work-related vocal stresses and to maintain psychological and vocal well-being throughout the university career. Gender and age-related aspects should be considered., Competing Interests: Declaration of competing interest The authors declare that no conflicts of interest exist., (Copyright © 2023 The Voice Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Endomyocardial biopsy (EMB) is a well-established procedure for the diagnosis of specific myocardial diseases and represents the gold standard in monitoring allografts after heart transplantation. In our study, we compared 2 different approaches for harvesting EMB in order to optimize patient safety and efficacy of the procedure., Methods: As a standard approach for harvesting EMB, a venous introducer sheath was inserted percutaneously via the internal jugular vein using the Seldinger technique. Thereafter, a bioptome was repeatedly introduced throughout this sheath into the right ventricle (RV), each time passing the tricuspid valve (TV). Alternatively, a coronary sinus catheter was inserted via an introducer sheath placed in the subclavian vein and only once was introduced into RV cavity. Hence, just a unique passage of TV was required. Thereafter, a bioptome was introduced via this catheter and precisely guided to the targeted biopsy site., Results: A standard approach was used with 34 patients, and a modified technique was used with 37 patients. Patient characteristics were comparable in both cohorts, and analyses of peri-procedural parameters identified only marginal differences between the groups. Interestingly, the number of harvested tissue samples per procedure was higher in the modified approach compared to the standard approach. No complications occurred., Conclusion: The modified approach for EMB is a safe procedure. The facilitated bioptome-guidance and enhanced protection of TV may prevent periprocedural complications., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Thermoresponsive polymers with lower critical solution temperatures (LCSTs) are of significant interest for a wide range of applications from sensors to drug delivery vehicles. However, the most widely investigated LCST polymers have nondegradable backbones, limiting their applications in vivo or in the environment. Described here are thermoresponsive polymers based on a self-immolative polyglyoxylamide (PGAM) backbone. Poly(ethyl glyoxylate) was amidated with six different alkoxyalkyl amines to afford the corresponding PGAMs, and their cloud point temperatures ( T cp s) were studied in water and buffer. Selected examples with promising thermoresponsive behavior were also studied in cell culture media, and their aggregation behavior was investigated using dynamic light scattering (DLS). The T cp s were effectively tuned by varying the pendent functional groups. These polymers depolymerized end-to-end following the cleavage of end-caps from their termini. The structures and aggregation behavior of the polymers influenced their rates of depolymerization, and, in turn, the depolymerization influenced their T cp . Cell culture experiments indicated that the polymers exhibited low toxicity to C2C12 mouse myoblast cells. This interplay between LCST and depolymerization behavior, combined with low toxicity, makes this new class of polymers of particular interest for biomedical applications.

It is no surprise that seniors' care is an important focus across Canada. Seniors are the fastest growing age group in Canada, and it is not uncommon for this population to have high comorbidity rates, functional impairments and a significant risk of decline. It is essential to support the public in remaining healthy as they age and identify what is truly important to them., (Copyright © 2019 Longwoods Publishing.)

Resident and family councils aim to improve resident and family satisfaction, but guidelines for councils are scarce. This project developed a toolkit and tested its ability, along with networking meetings, to promote successful councils. Nine continuing care sites participated with residents, family and staff from each site who received the toolkit, completed surveys, attended meetings and participated in post-pilot interviews. Participants found that the toolkit helped improve council function and, with the networking meetings, increased participation. All sites found the toolkit and networking meetings to be valuable resources and had a strong desire to have them available in the future., (Copyright © 2019 Longwoods Publishing.)

Background: Heart transplantation (HTX) is an established therapy for end-stage heart disease. The aim of this study was to determine whether application of oral bisphosphonates is effective in preventing osseous complications after HTX., Methods: Thirty-three cardiac transplant recipients were treated with alendronate 70 mg/wk or risedronate 35 mg/wk in combination with 1000 mg calcium and 800 IU vitamin D. Markers of bone metabolism and dual-energy X-ray absorptiometry (DXA) were determined directly after HTX and 2 years later. Primary endpoints were changes in bone mineral density (BMD), markers of bone metabolism (osteocalcin, crosslaps), serum levels of the cytokines osteoprotegerin (OPG), receptor activator of NF kappa-B ligand (RANKL), and incidence of fractures., Results: Eight patients presented with osteoporosis, and 16 patients with osteopenia by DXA without prevalent fractures. Over 2 years, the BMD improved in 2 patients from osteoporosis to osteopenia, and overall BMD remained stable, and fractures did not occur. In addition, the serum levels of OPG increased (P < .0005), and the RANKL levels (P < .001) as well as the RANKL/OPG-ratio decreased significantly (P < .0005). The serum crosslaps showed no significant changes. The BMD showed a significant association with the increased 25-vitamin D levels only in females (P < .001)., Conclusions: In heart transplanted patients, weekly oral bisphosphonates in combination with calcium and vitamin D supplementation preserved bone mass, prevented uncoupling of bone resorption/formation and fractures. Bone density should be measured and adequately treated, that is, with regular bisphosphonates., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Depressive symptoms are highly prevalent in nursing home (NH) residents. The relationship between depressive symptoms and everyday competence in terms of basic (BaCo) and expanded everyday competence (ExCo; see Baltes et al., 2001) in the NH setting is, however, not clear. Applying Lewinsohn's depression model, we examined how residents' BaCo and ExCo relate to their depressive symptoms. Furthermore, we investigated the mediating role of perceived control., Methods: Cross-sectional data from 196 residents (M age = 83.7 years, SD = 9.4 years) of two German NHs were analyzed. Study variables were assessed by the Geriatric Depression Scale-Residential (GDS-12R), maximal gait speed (BaCo), proxy ratings of residents' in-home activity participation, and self-initiated social contact done by staff (ExCo). Structural equation modeling (SEM) was used and a simulation study was included to determine power and potential estimation bias., Results: At the descriptive level, one quarter of the residents showed symptoms of depression according to the GDS-12R cut-off criterion. Residents' BaCo and ExCo were independently and equally strongly associated with their depressive symptoms in the SEM analysis. These findings were affected neither by cognitive impairment, sex, nor age. Perceived control mediated between BaCo but not ExCo and depressive symptoms., Conclusion: Future research needs to follow the connection between residents' everyday competence and their depressive symptoms longitudinally to better understand the underlying mechanisms.

The aim of this review was to evaluate current evidence regarding the effects of interventions on physical activity in the subgroup of nursing home residents as well as to critically review the assessment methods used in this regard. Published studies through January 2015 were searched in The Cochrane Library, PubMed, CINAHL, Web of Knowledge, PsycInfo, Psyndex, Psycarticles, CC Med, and DissOnline; and by manual search. For randomized controlled trials (RCTs) to be included, an intervention had to be conducted with nursing home residents aged 65 years and above and physical activity had to be assessed using standardized, quantitative methods. Study quality was evaluated using an established Cochrane rating tool for RCTs. Eight studies met the inclusion criteria. Only one intervention study with main focus on a modification of physical activity behavior could be identified. Physical activity assessments used in the studies were partly limited regarding objectivity or psychometric quality. Hence, the documentation of effects of interventions is restricted. Six studies reported significant increases of physical activity in nursing home residents and thus positive intervention effects, which points at the feasibility and high potential of intervention programs to promote physical activity in this setting. Enhanced individual contact as well as physical exercise combined with behavioral interventions and the inclusion of nursing staff seems to be most effective in this regard. As only one study involved post-intervention follow-up assessments, sustainability of effects remained unclear.

Background: Physical activity (PA) is not only an important marker of physical impairment, but also a pathway to improve quality of life and enhance cognitive and social functioning of old individuals. Yet, making interventional use of PA training as a means for prevention and enhancement of quality of life of nursing home residents has found very limited attention worldwide so far. That said, the project 'Long-term Care in Motion' (LTCMo) as a part of the INNOVAGE consortium (funded by the European Commission) has the following aims: Overall: Install and assess a socially innovative intervention in the nursing home ecology. Concrete: (a) Conceptualization of a multidimensional intervention program (resident and staff oriented) with the potential to promote PA in nursing home residents; (b) Mixed-methods assessment of the program based on automated recording as well as questionnaire data., Methods/design: LTCMo's PA-related intervention has several components which are applied in parallel manner: (1) Residents are engaged in a physical exercise program that is based on multiple approaches: supervised group sessions, a serious games approach, and specific training in severely impaired persons; (2) Staff members will receive a competence training with a focus on PA motivation and facilitation of residents' PA engagement. Primary outcome assessment (movement-related behavior of residents) is completely conducted by means of automated data collection strategies (accelerometer-based activity recording, sensor-based life space recording). This is enriched by a broad range of secondary outcomes (e.g., cognitive performance, depression of residents; behavioral and attitudinal components of staff). Pre-, post- and 3-month follow-up assessment will take place in the target intervention setting as well as in a waiting control condition in which we will also replicate the training and its assessment in a later step., Discussion: Although we are faced with methodological challenges (e.g., rather small sample size; no randomized control trial), we believe that our approach has something to offer and indeed has some unique characteristics that may have the potential to contribute to the enhancement of nursing home residents' quality of life and at the same time further PA-related research with vulnerable populations at large., Trial Registration: Current Controlled Trials ISRCTN96090441. Registered 31 July 2014.

Background: The aim of the substudy that was conducted as part of the project "Bewertung neuer Technologien durch Bewohner und Personal im Altenzentrum Grafenau der Paul Wilhelm von Keppler-Stiftung und Prüfung des Transfers ins häusliche Wohnen" (BETAGT) was to have residents and staff members in nursing homes with limited technological equipment complete a questionnaire about their life-long technological experiences and their general technological attitude. Furthermore, specific technological devices and systems were evaluated in terms of their potential with respect to safety, privacy, or help in decreasing burden. Data were collected using a newly developed brief questionnaire., Sample and Methods: A total of 84 residents and 109 staff members sampled from 11 different institutions were asked about their life-long technology experiences, general attitudes towards technology as well as attitudes towards specific technological devices. Residents' opinions were assessed via brief structured interviews; a structured questionnaire was given to the staff members to complete. The technological devices to be evaluated were introduced via pictured descriptions., Results: Residents and staff members showed a positive attitude towards technology. With regard to the potential of new technologies, residents and staff members expect different effects on several dimensions of quality of life. Both groups rated the potential of the dimension of safety to be highest., Conclusion: Contrary to widely held opinion, older adults living in institutions do not, in general, seem to be too critical about new technology. From the staff members' point of view, modern technology can be integrated into daily care routines of a nursing home, but the potentials of new technologies are considered in a very differential manner.

Case Report: A 51-year-old woman diagnosed as having valvular cardiomyopathy since age 34 was admitted for an evaluation for a heart transplant because of progressive congestive heart failure. When antiphospholipid antibodies were detected, the diagnosis of a thus far undetected systemic lupus erythematosus (SLE) was confirmed, manifesting primarily by cardiac involvement and an antiphospholipid antibody syndrome. Despite an advanced stage of heart failure, the patient responded well to azathioprine. Nevertheless, the potential necessity of a heart transplant remained. Its atypical presentation impeded a timely diagnosis of SLE significantly, however, in retrospect the correct diagnosis would have been possible at an earlier time point., Conclusion: Though rare, SLE represents an important differential diagnosis in cases of severe valvular disease and cardiomyopathy, particularly in young women.

Objectives: To evaluate the in vitro effects of rapamycin in human transitional cell carcinoma and to clarify the possible rapamycin-hypoxia interactions., Methods: Monolayer cultures of RT112 (G1), RT4 (G1-2), T24 (G3), and SUP (G4) cells were incubated in medium with or without rapamycin (10 microM, 100 microM) in different gaseous conditions (1% oxygen plus 5% carbon dioxide plus 94% nitrogen or 95% oxygen plus 5% carbon dioxide or 21% oxygen plus 78% nitrogen). Cell vitality and proliferation were determined using the microculture tetrazolium assay. Apoptotic cells were quantified by flow cytometry. Enzyme-linked immunosorbent assay was used to visualize inhibition of the mammalian target of rapamycin (mTOR) by rapamycin and synthesis of vascular endothelial growth factor., Results: Rapamycin delayed proliferation of cancer cell lines but did not induce apoptosis. No direct hypoxia interactions of rapamycin were found. Enzyme-linked immunosorbent assay gave evidence of mTOR inhibition in all cell lines and a significant decrease of hypoxia-induced vascular endothelial growth factor synthesis., Conclusions: Because proliferation in bladder cancer cells was delayed, but no apoptosis was induced, cell cycle arrest caused by rapamycin was feasible. Rapamycin decreased hypoxia-induced synthesis of vascular endothelial growth factor. These findings should be substantiated in an animal model to verify the antiangiogenetic effects of rapamycin.

The effect of subcutaneous injection of physiological saline (given as 'placebo' in a randomized double-blinded placebo-controlled study) on immunocompetent cells from healthy individuals was analyzed. In two studies in 1998/1999 and 2002, 16 and 13 healthy individuals, respectively, were injected subcutaneously with 1 ml physiological saline twice a week for up to 12 weeks. Lymphocytes were isolated before and during exposure and incubated with recall antigens (purified protein derivative [PPD], tetanus toxoid [TT], bacillus Calmette-Guerin [BCG]). The production of T-helper type 1-, type 2-, and macrophage/monocyte-related cytokines was analyzed by ELISA. There was a significant increase of the recall-antigen-induced production of IFNgamma, IL-5, IL-13, TNFalpha, and GM-CSF in both groups during the observation period. Subcutaneous injection of placebo, therefore, enhances immunoreactivity. Psychological aspects, activation of the autonomous nerve system or local activation of mast cells or dendritic cells may be responsible for this phenomenon.

The aim of the study was to investigate how exposure to mistletoe extracts in vivo may influence cellular immune reactions by peripheral blood mononuclear cells (PBMC). 47 healthy individuals were exposed for twelve weeks either to Iscador Quercus special (IQ; rich in mistletoe lectin [ML]) (n = 16), to Iscador Pinus (IP; poor in ML but rich in viscotoxin) (n = 15), or to placebo (physiological saline) (n = 16). PBMC were isolated before exposure, during exposure in week 4, 8 and 12, as well as 13 weeks after last exposure (week 25) and incubated for 7 days with IQ or IP. Proliferative response and cytokine release were determined (type 1 cytokines: interferon [IFN]-gamma, tumor necrosis factor [TNF]-gamma, type 2 cytokines: interleukin [IL]-5, IL-13, macrophage/ monocyte-cytokines: IL-1, TNFalpha). IP- and IQ incubation of PBMC from non-exposed individuals lead to a significant increase of proliferation and production of all cytokines. There was a significant increase of IQ-induced TNFalpha (but not IL-1) production by PBMC in week 25 in individuals receiv-type 2-cytokines IL-5 and IL-13 significantly decreased during the observation period (p < 0.05 compared to placebo in week 8). These data indicate that IP seems to contain an antigen, which decreases type 2 reactivity. Furthermore, a component present preferentially in IQ seems to activate the production of the monocyte/ macrophage-related cytokine TNFalpha by PBMC. Intriguingly, also in individuals receiving placebo injections immunological alterations were detected during the observation period.

Mistletoe extracts exert immunomodulatory properties in vivo and in vitro, and these effects have been related mainly to mistletoe lectin 1 (ML-1). Recently, a new chitin-binding mistletoe lectin (cbML) has been isolated and structurally characterized in these extracts. Aim of the present study was, therefore, to evaluate whether this cbML also affects immunocompetent cells and can for instance activate B-cells to produce anti-cbML-specific antibodies. Sera from patients with different tumors who were treated with the mistletoe extract ABNOBAviscum Mali (AM) 4 for at least 18 weeks were analysed before therapy and after 3, 6, 9, 12, 18, and 24 weeks. Sera were tested by ELISA against ML-1, -3, and cbML, isolated from a single mistletoe plant collected from an apple tree (Malus domestica). Eight of the 26 patients (31%) had IgG anti-cbML antibodies already before therapy, while only four had anti-ML-1 and -3 antibodies. Of the 18 anti-cbML negative patients before therapy 54% developed these antibodies during therapy, and there was a significant increase in anti-cbML antibody titers. In contrast, anti-ML-1 or -3-antibodies developed in almost 100% of the 25 patients being negative before therapy. These data indicate that cbML can induce immunological responses in patients treated with mistletoe extracts, although it seems to have lower antigenicity. Interestingly, anti-cbML antibodies can be observed in a low incidence also in individuals, not having yet received mistletoe therapy.

Mistletoe extracts exert immunomodulatory properties on immunocompetent cells of the innate as well as the specific immune system. These effects have been mainly ascribed to mistletoe lectin 1 (ML-1) present in most of the extracts. However, it became evident that also other components of these extracts may induce immunological reactions, and especially viscotoxins (VT) may be of relevance. Aim of the study was, therefore, to evaluate whether VT like ML-1 could activate B-cells and lead to the production of VT-specific antibodies. Sera from 26 patients with different tumours who were treated with the mistletoe extract ABNOBAviscum Mali (AM) 4 for at least 18 weeks were analysed before therapy and after 3, 6, 9, 12, and 18 weeks. Sera were tested by ELISA against the four viscotoxins A1, A2, A3, B, as well as against ML-1. Within the observation period twenty-four (92%) of the 26 patients developed antibodies to at least one of the four VT and 25 (96%) to ML-1. In most instances, anti-VT antibodies appeared after 6-9 weeks of treatment. The antibodies were predominantly of the IgG type belonging preferentially to the IgG1 and IgG3 subclass. IgE antibodies were found only to VT-B and to ML-1. There was no relation between the development of antibodies to VT and ML-1, and also cross-reactivity could be excluded with high probability. These data indicate that not only ML-1 but also VT induce immunological responses in patients treated with mistletoe extracts. Whether there is any relationship to the postulated anti-tumour effect of mistletoe extracts has, however, still to be evaluated.

Background: Several studies have been performed in tumour patients to analyse the immunological response to mistletoe extracts. Considering the fact that these extracts are given subcutaneously in most instances, the kind of application resembles a typical immunization schedule. We therefore wanted to see how those extracts act on immunocompetent cells of healthy individuals hoping that this kind of provocation test may give new informations about a more specific application of these extracts in certain diseases., Subjects/methods: 47 healthy individuals were exposed for twelve weeks either to Iscador Quercus special (IQ) known to be rich in mistletoe lectin (ML)-1 (n = 16), to Iscador Pini (IP) being poor in ML-1 but enriched in viscotoxins (n = 15), or to placebo (physiological saline) (n = 16) in a randomised, double-blinded placebo-controlled study. Humoral immunoreactivity was analysed by measuring antibodies towards the two compounds ML-1 and viscotoxin VA2 (VA2). Sera were collected in intervals of four weeks up to week 12 and again three months after last exposure., Results: None of the subjects had antibodies to ML-1 or VA2 before exposure. In week 12, anti-ML-1 antibodies of the IgG-type were found in all 16 IQ-treated individuals but only 6 of the 15 probands exposed to IP. In contrast, anti-VA2 IgG-antibodies could be detected in all individuals of both groups. The antibodies were preferentially of the IgG1 and IgG3 type while antibodies of the IgA and IgM type were produced only in a few probands. Antibodies of the IgE-type occurred only in the IQ-exposed individuals and were directed against ML-1 but not VA2. None of the probands receiving placebo developed antibodies to ML-1 or VA2. Severe side effects were not observed in any of the probands., Conclusions: These data obtained in healthy individuals clearly indicate that IQ and IP-extracts can induce antigen-specific humoral responses. They may, therefore, provide, a solid basic for the evaluation of the humoral immune response in disease states.

Rat brain cortex slices were prepared in order to study the influence of DU 24565 (6-nitroquipazine) and quipazine on the accumulation of tritium, and to investigate the effects of DU 24565 on the electrically evoked (3 Hz) tritium overflow from slices preincubated with 3H-serotonin (3H-5-HT) or 3H-noradrenaline (3H-NA). The influence of DU 24565 and quipazine on the activity of MAO was studied in rat brain homogenates, using labelled serotonin as a substrate. In cortex slices preincubated with either 3H-5-HT or 3H-NA, DU 24565 increased the electrically evoked 3H overflow (higher potency in slices preincubated with 3H-5-HT; the percentage of 3H accounted for by unmetabolized 3H-5-HT was also increased). The facilitatory effects of DU 24565 on evoked 3H overflow were abolished when the respective monoamine uptake mechanisms had previously been blocked by citalopram and cocaine, respectively. The inhibitory effects of unlabelled 5-HT and NA on the evoked 3H overflow from cortex slices preincubated with 3H-5-HT were not altered by DU 24565. Similarly, the drug did not affect the inhibition by NA of the evoked 3H overflow from cortex slices preincubated with 3H-NA. Quipazine was a weak and non-selective inhibitor of the accumulation of 3H-5-HT and 3H-NA. DU 24565 was about 65 times more potent and about 1100 times more selective than quipazine as an inhibitor of 3H-5-HT accumulation, and it was also superior to citalopram and paroxetine in this respect.(ABSTRACT TRUNCATED AT 250 WORDS)

Rat brain tissues preincubated with [3H]serotonin ([3H]5-HT) or [3H]norepinephrine ([3H]NE) were superfused in the presence of an inhibitor of serotonin or NE uptake, respectively. The electrically (3 Hz) evoked [3H]5-HT release from slices of the medulla oblongata [containing the nucleus tractus solitarii (NTS)] from Wistar rats was inhibited by 5-HT and NE, and these effects were counteracted by metitepine and phentolamine, respectively. The evoked [3H]5-HT release in slices from the cortex, medulla oblongata, and hypothalamus of 5-7-, 9-11-, and 19-22-week-old spontaneously hypertensive rats (SHR) did not differ from that in slices from age-matched Wistar-Kyoto rats (WKY). Nor was there any difference between strains for: the inhibitory effects of 5-HT and NE and the facilitatory effect of metitepine on the evoked [3H]5-HT release; the shift to the right of the concentration-response curves of 5-HT and NE by metitepine and phentolamine, respectively; the potassium (12 mM)-evoked [3H]5-HT release from cortex synaptosomes and its inhibition by 5-HT; the electrically evoked [3H]NE release in cortex slices, its inhibition by NE, and the shift to the right of the concentration-response curve of NE by phentolamine. The results provide evidence that 5-HT release in the rat brain NTS can be inhibited by 5-HT receptors and alpha-adrenoceptors. 5-HT release and its modulation by presynaptic 5-HT1 receptors and alpha 2-adrenoceptors as well as NE release and its modulation by presynaptic alpha 2-adrenoceptors do not differ between SHR and WKY rats. It may be of therapeutic relevance that according to these results the effects of 5-HT1 receptor agonists activating presynaptic 5-HT autoreceptors are not attenuated in this type of hypertension. It has been suggested that such agonists can be developed as a new class of antihypertensive drugs.

Rat brain cortex slices and synaptosomes preincubated with [3H] serotonin were used to study the effects of the 5-HT1 receptor agonist RU 24969 (5-methoxy-3-(1,2,3,6-tetrahydro-4-pyridinyl)-1H-indole) on the electrically (3 Hz) evoked 3H overflow from superfused slices and the potassium (12 mmol/l)-evoked 3H overflow from superfused synaptosomes. In slices superfused in the presence of 6-nitroquipazine (an inhibitor of serotonin uptake), the electrically evoked overflow was inhibited by RU 24969 and the reference compound serotonin (maximum inhibition obtainable: by about 50 and 60%, respectively; IC25 and IC30: 33 and 150 nmol/l, respectively). The inhibitory effect of RU 24969 on the evoked overflow was attenuated by cyanopindolol (a beta-adrenoceptor blocker with antagonistic properties at 5-HT1 receptors). In the absence of 6-nitroquipazine, RU 24969 did not increase the basal efflux and tended to be more potent in inhibiting the evoked overflow than in the presence of 6-nitroquipazine. The correlation of the release-inhibiting potencies of serotonin receptor agonists with their affinities for 5-HT1B binding sites (Engel et al., 1986) was slightly improved by inclusion of RU 24969, whereas that with the affinities for 5-HT1A binding sites (which was worse than the former correlation) was not changed. In synaptosomes superfused in the presence of 6-nitroquipazine, RU 24969 inhibited the potassium-evoked overflow. The inhibitory effect of RU 24969 was antagonized by cyanopindolol, which by itself did not affect the evoked overflow. It is concluded that RU 24969 acts as a highly potent agonist (with an intrinsic activity of about 0.8) at the presynaptic serotonin autoreceptor in the rat brain cortex. Furthermore, the present results support the assumption that these receptors belong to the 5-HT1B subtype.