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The goal of the work was to study the effect of the cannabinoid receptor agonist WIN55,212-2 and the cannabinoid type 1 receptor antagonist AM251 on electrophysiological changes in the hippocampus and the medial septal region (MS) induced by the intracerebral administration of excitotoxin kainic acid. Kainate injected into the right brain ventricle provoked persistent seizures (status epilepticus, SE) in all rats. A morphological analysis of the right hippocampus performed one month after the SE revealed the death of neurons, which was most pronounced in the hilus of the dentate gyrus and in the CA3a field of the dorsal hippocampus. In brain slices taken one month after the SE, the spontaneous activity of MS neurons and population EPSP (pEPSP) in the CA1 field of the hippocampus evoked by the stimulation of Shaffer collaterals (SC) was recorded; the changes in the activity were compared with the activity in slices of healthy animals injected with normal saline (“control slices”). It was found that the activity in MS slices from the brain of animals injected with kainic acid (“kainate slices”) was almost twice higher than in the control. After the application of WIN55,212-2, the frequency of discharges in the control did not change, whereas in kainate slices, the level of neuronal activity decreased to the control value. The application of AM251 led to an increase in the frequency of discharges in the control and its decrease in kainate slices. The registration of pEPSPs in the hippocampal slices revealed a twofold increase in the responses to SC stimulation in kainate slices compared with those in the control, i.e., an abrupt increase in neuronal excitability. A tendency for a decrease in excitability after the application of WIN55,212-2 and, conversely, for its increase by the action of AM251 was noted in evoked responses in the hippocampal kainate slices. Our results allow to assume the protective impact of cannabinoid agonist WIN55,212-2 on neuronal activity in the medial septum and hippocampus that disturbed by neurotoxic kainate influence. 

Synchrony in neuronal networks plays a crucial role in the functioning of the brain. Stability of synchrony is most desirable to prevent any emergent desynchrony due to natural events, internal or external disturbances. The brain might have its own mechanism to repair its desynchrony, otherwise, some external procedure might be necessary to restore synchrony. We propose here a mechanism to realize robust synchrony in neuronal networks against parameter drifting. A selective addition of cross-coupling links over and above the conventional diffusive coupling links is found [Saha et al. (2017)] recently that makes dramatic improvements in the stability of synchrony of dynamical networks and that saves synchrony against breakdown due to parameter drifting. We apply the concept to realize globally stable synchrony in neuronal networks and the desired effect of robust synchrony and, present our numerical studies with examples of network motifs and a larger network of neurons and using the Hindmarsh-Rose (HR) [Hindmarsh and Rose (1984)] slow-fast neuron model for each node of the networks.

Neurons of the substantia nigra are most prone to degeneration in Parkinson’s disease. The cause of their vulnerability remains unclear and knowledge of the molecular and microstructural features of the substantia nigra pars compacta will help understanding why nigral neurons are vulnerable to damaging factors. 
The present study was aimed to investigate the intranuclear inclusions of the nigral neurons, the Marinesco bodies and the Roncoroni rodlets, which origin and function are uncertain, using ubiquitin-, tyrosine hydroxylase-, nitric oxide synthase-, calbindin-, NeuN-, glutamic acid decarboxylase-, and  α-tubulin-immunohistochemistry and iron histochemistry with DAB enhancement.
Of the tested substances, tyrosine hydroxylase and nitric oxide synthase were revealed for the first time in the Marinesco bodies. Non-heme iron was found for the first time in both the Marinesco bodies and the Roncoroni rodlets. In accordance with previous studies, ubiquitin-immunoreactivity was demonstrated in the Marinesco bodies. Moreover, we describe some smaller round and dot-like ubiquitin-immunoreactive structures in the nucleus of melanized neurons. The found small ubiquitin-immunopositive structures within the nucleus are proposed to be the developmental stages of growing Marinesco bodies, whereas Marinesco bodies themselves seem to label the neurons with impaired function of proteasome. 

The aim of the current study was to examine the effects of chronic cholecalciferol administration (1.0, 2.5 or 5.0 mg/kg/day, s.c., once daily, for 14 days) on the anxiety-like and depression-like behaviors following long-term ovariectomy (12 weeks) in female rats. Cholecalciferol was administered to the ovariectomized (OVX) rats and OVX rats treated with 17β-estradiol after long-term absence of estrogen (17β-E2, 0.5 µg/rat, s.c., once daily, for 14 days). Anxiety-like behavior was assessed in the elevated plus maze (EPM), depression-like behavior was assessed in the forced swimming test (FST), locomotor and grooming activities were assessed in the open field test (OFT). The treatment with cholecalciferol (1.0 mg/kg/day, s.c.) in the OVX rats after long-term absence of estrogens induced antidepressant-like effect (p<0.05). Moreover, cholecalciferol in this dose plus 17β-E2 more markedly exhibited antidepressant-like effect in the OVX rats after long-term ovariectomy (p<0.05). The OVX rats treated with cholecalciferol at doses of 1.0 mg/kg and 2.5 mg/kg demonstrated a decrease of anxiety-like behavior in the EPM. The combination of cholecalciferol at doses of 1.0 and 2.5 mg/kg with a low dose of 17β-E2 more effectively decreases anxiety-like behavior in the OVX rats after long-term estrogen deficiency than17β-E2 alone. This work promotes more effective creation of novel therapeutic targets and strategies for affective-related disorders treatment in female subjects with long-term estrogen deficiency.

The aim of the present study was to explore the effects of 8-OH-DPAT, 5-HT1A receptor agonist and NAN-190, 5-HT1A receptor antagonist on anxiety-related behavior in the adult gonadectomized (GDX) male rats. Moreover, another goal of this work was to investigate whether the combination of 8-OH-DPAT or NAN-190 plus testosterone propionate (TP) could affect anxiety-like behavior more than TP alone in the adult GDX rats. Two weeks after gonadectomy, GDX rats were subjected by treatments with the solvent, TP (0.5 mg/kg, s.c.), 8-OH-DPAT (0.05 mg/kg, s.c.), NAN-190 (0.1 mg/kg, i.p.), 8-OH-DPAT in a combination with TP or NAN-190 in a combination with TP during 14 days. Experimental groups of GDX rats and control group of intact males were then tested in the elevated plus maze (EPM) and the open field test. 8-OH-DPAT treatment failed to modify anxiety-like behavior of GDX rats in the EPM as compared to the GDX rats given with oil solvent. NAN-190 injected alone or in combination with TP to GDX rats resulted in a significant anxiolytic-like effect as compared to the GDX given with oil solvent or TP application. Our data indicate that the combination of NAN-190 and TP is more effective than TP alone in GDX rats inducing a more profound anxiolytic-like effect in the EPM. Thus, the results of this study suggest that effects of 5-HT1A receptor agonist/antagonist can modify anxiety level in opposite direction in male rats after gonadectomy.

The role of chaos in biological information processing has been established as an  important breakthrough of nonlinear dynamics, after the early pioneering work of J.S. Nicolis and notably in neuroscience by the work of Walter J. Freeman and co-workers spanning more than three decades.  In this work we revisit the subject and we further focus on novel results that reveal its underlying logical  structure when  faced with the cognition of ambiguous stimuli. We demonstrate, by utilizing a minimal model for apprehension and judgement related to Bayesian updating,  that the fundamental characteristics of a biological processor obey in this case an extended, non-Boolean, logic which is characterized as  a quantum logic. And we realize that in its essence the role of chaos in biological information processing accounts for, and is fully compatible with, the logic of “quantum cognition” in psychology and neuroscience.