Neuropeptide substance P (SP) has reinforcing and memory facilitating effects after its peripheral or central application. Rats self-inject SP into the ventromedial caudate-putamen and SP microinjections into the basal forebrain induce place preference with a simultaneous increase of dopamine level. In the amygdaloid body SP positive neurones and terminals have been identified. The aim of the present study was to examine the possible reinforcing effects of SP in the basolateral amygdala (ABL). CFY male rats were conditioned in two-compartment passive avoidance paradigm and place preference was examined in two-compartment-box and in circular open field. Animals were microinjected bilaterally with 10 ng SP, 100 ng SP or vehicle solution (0.4 ml/side) into the ABL. Results showed that post-shock infusion of 10 ng SP significantly enhanced passive avoidance learning while 100 ng SP was ineffective. In two-compartment-box and in circular open field place preference did not develop after SP treatments, however. Our data are the first to demonstrate that SP in the ABL is involved in learning and memory processes related to aversive situations. Results that SP microinjections were not followed by rewarding-reinforcing consequences in place preference paradigms indicate that the local SP network in the ABL is not involved in neuronal circuitry responsible for addictive behaviour.
While food intake and body weight are under homeostatic regulation, eating is a highly motivated and reinforced behavior that induces feelings of gratification and pleasure. The chemical senses (taste and odor) and their evaluation are essential to these functions. Brainstem and limbic glucose-monitoring (GM) neurons receiving neurochemical information from the periphery and from the local brain milieu are important controlling hunger motivation, and brain gut peptides have a modulatory role on this function. The hypothalamic and limbic forebrain areas are responsible for evaluation of reward quality and related emotions. They are innervated by the mesolimbic dopaminergic system (MLDS) and majority of GM neurons are also influenced by dopamine. Via dopamine release, the MLDS plays an essential role in rewarding-reinforcing processes of feeding and addiction. The GM network and the MLDS in the limbic system represent essential elements in the neural substrate of motivation.
Authors:Julia O Fedotova, G Hartmann, L Lénárd and NS Sapronov
The purpose of this work was to study the role of 5-HT1A receptors on the level of anxiety in adult intact and ovariectomized (OVX) female rats. The influence of chronic administration of 5-HT1A receptor agonist 8-OH-DPAT (0.05 mg/kg, s.c.) and 5-HT1A receptor antagonist NAN-190 (0.1 mg/kg, i.p.) given for 14 days alone or in combination with 17µ-estradiol (0.5 µg i.m./rat/day) was studied on behavior in the elevated plus maze. In intact females administration of NAN-190 resulted in significant increase in the number of enterings and the time spent on the open arms in every phase of the estrous cycle, however, 8-OH-DPAT failed to modify these parameters. In OVX females 8-OH-DPAT alone or in combination with 17µ-estradiol significantly increased the number of enterings and time spent on the open arms. On the contrary, NAN-190 alone or in combination with 17µ-estradiol in OVX females failed to evoke behavioral changes in the elevated plus maze. Thus, the 5-HT1A receptor antagonist NAN-190 induced anxiolytic effect in intact female rats, while 5-HT1A receptor agonist 8-OH-DPAT produced an anxiolytic profile on OVX rats. Results of this work specify the involvement of 5-HT1A receptors in behavioral mechanisms of anxiety in OVX female rats.
Authors:Julia O Fedotova, G Hartmann, L Lénárd and NS Sapronov
The influence of chronic administration of 5??1? receptor agonist 8-OH-DPAT (0.05 mg/kg, s.c.) and 5-??1? receptor antagonist NAN-190 (0.1 mg/kg, i.p.) injected for 14 days alone or in combination with 17Ãµ-estradiol (0.5 Ãµg i.m./rat/day) was studied on passive avoidance performance (PAR) and on behavior in the open field test in adult intact and ovariectomized (OVX) female rats. Administration of 5-??1? receptor antagonist NAN-190 alone significantly improved PAR (p<0.05) in intact females with proestrus and estrus and in OVX females. Administration of 5-??1? receptor agonist 8-OH-DPAT alone or in combination with 17Ã-estradiol significantly (p<0.05) improved PAR in OVX rats and failed to normalize PAR in intact rats with proestrus and estrus. Results of the work specify the involvement of 5-??1? receptors in the mechanisms of passive avoidance learning in OVX female rats.
Authors:A. Doros, B. Nemes, Z. Máthé, A. Németh, E. Hartmann, Á. P. Deák, Zs. F. Lénárd, D. Görög, I. Fehérvári, Zs. Gerlei, J. Fazakas, Sz. Tóth and L. Kóbori
Hepatic artery complication represents recognized sequel of liver transplantation that carries significant morbidity and mortality. Besides retransplantation, hepatic artery recanalization is provided surgically, or by percutaneous angioplasty and stent placement. This study provides an analysis of a single center experience comparing surgical and interventional treatments in cases of early hepatic artery complications.
In this retrospective single center study, 25 of 365 liver transplant recipients were enrolled who developed early hepatic artery complication after transplantation. Percutaneous intervention was performed in 10 cases, while surgical therapy in 15 cases. Mean follow-up time was not different between the groups (505±377 vs. 706±940 days, respectively).
6 patients in the Intervention Group and 10 patients in the Surgery Group are alive. The retransplantation rate (1 and 3) was lower after interventional procedures, while the development of biliary complications was higher. The mortality rate was higher after operative treatment (2 and 5).
Interventional therapy is a feasible and safe technique for treatment of early hepatic artery complication after transplantation. Being less invasive it is an invaluable alternative treatment having results comparable to surgical methods.
Authors:E. Hartmann, A. Németh, Gy. Juharosi, Zs. Lénárd, P. Á. Deák, V. Kozma, P. Nagy, Zs. Gerlei, I. Fehérvári, B. Nemes, D. Görög, J. Fazakas, L. Kóbori and A. Doros
Hepatocellular carcinoma, which has developed in liver cirrhosis is a disease where liver transplantation can provide a cure both for the tumour and the underlying liver damage. However, patients can only be transplanted when the tumour number and size do not exceed the Milan criteria. Tumour ablation methods — such as radiofrequency ablation — can provide a chance to make the patient eligible for transplantation. Among the 416 Hungarian liver transplanted patients there are 6 who had received different types of ablative therapy as bridging therapy in different institutions. On the basis of analysis of the patients' data we created a guideline for the treatment of cirrhotic patients with hepatocellular carcinoma with the aim of developing a uniform Hungarian approach.