Early postnatal development of the lumbar vertebrae in male Wistar rats: double staining and digital radiological studies

The aim of the study was to evaluate the physiological developmental changes of male rats’ lumbar vertebrae during the first 22 days after birth. Morphology and mineralisation of lumbar vertebrae were evaluated using double-staining and digital radiography system, which allowed vertebral width and optical density to be determined. Pup weight, crown-rump length, body mass index and vertebral width increased during postnatal period and significantly correlated with their age. Bone mineralisation, as measured by optical density, did not show any significant differences. The complete fusion of the primary ossification centres had a cranio- -caudal direction and started on day 19 after parturition but was incomplete by day 22. It could be concluded that, unlike significant age-related increase of vertebral size, mineralisation was only slightly elevated during evaluated postnatal period. The method described is supplementary to alizarin red S staining as it provides both qualitative and quantitative data on mineralisation in a similar manner to micro computed tomography but does not allow 3 dimensional and microarchitecture examination

Immunocytochemical detection of calretinin in the claustrum and endopiriform nucleus of the chinchilla

Calretinin (CR) as a buffer and sensor protein plays an important role in regulatory processes of Ca²⁺ and anty-apoptotic cellular protection. In the present study, immunohistochemical peroxidase- antiperoxidase (PAP) method was used in order to determine the numbers, morphology, morphometry and distribution pattern of CR in neurons of the chinchilla’s claustrum (Cl) and endopiriform nucleus (EN). In Cl and EN the presence of several classes of neurons with different immunoreactivity to CR was found. In Cl, CR-immunoreactive (IR) neurons were predominantly found in close vicinity to insular border while CR-IR neurons were evenly scattered throughout EN. In general, immunoreaction to CR was observed in neuronal cytoplasm, nucleus and in fibres-like nerve extensions. Statistical analysis showed the differences between average large diameter as well as cross-sectional area of CR-IR neurons present in Cl and EN. It is suggested, that CR acting as a calcium binding protein may play a role in neuronal network. Further co-localization studies are necessary to fully elucidate neurophysiology and neuropathology of the chinchilla’s Cl and EN neurons

Effect of feeding with bilberry fruit on the expression pattern of alphaCaMKII in hippocampal neurons in normal and diabetic rats

αCaMKII, widely occurring in the central nervous system, plays a significant role in cognitive processes. It is well known that diabetes is a risk factor that may trigger brain atrophy, cognitive dysfunction and finally lead to memory loss. Antioxidants richly present in bilberry fruits are believed to have significant effects on diabetes-related brain dysfunctions mainly due to their abilities to modulate neurotransmitter release that lead to reduction of the negative impact of free radicals on cognitive processes. The aim of the present research was to immunohistochemically investigate the expression patterns of αCaMKII in hippocampal neurons from non-diabetic, diabetic and diabetic rats fed with an extract of bilberry fruit. The obtained results show that in comparison to the control group, in diabetic rats hippocampal neurons immunoreactive (ir) to αCaMKII were swollen and the lengths of the neuronal fibres were reduced. Further study shows that in diabetic rats fed with bilberry fruit, αCaMKII-positive nerve fibres were significantly longer when compared to the groups of diabetic and control rats. Additionally, we observed statistically significant changes in the average larger diameter of αCaMKII-ir hippocampal neurons between groups of diabetic rats (with vs. Without supplement of bilberry fruit). The results of the present work suggest that antioxidants present in bilberry fruits influence the morphology of and possibly exhibit beneficial and neuroprotective effects on hippocampal neurons during diabetes. It is likely that changes in the appearance of αCaMKII-expressed hippocampal neurons may reflect the diabetes-evoked rise in Ca²⁺ level in the cerebral nerve terminals. The present research extends our knowledge of preventive mechanisms for cognitive dysfunctions occurring in the brain during diabetes

Distribution and immunohistochemical characteristics of cocaine- and amphetamineregulated transcript-positive nerve elements in the pelvic ganglia of the female pig

Cocaine- and amphetamine-regulated transcript (CART) peptides are widely expressed not only in the brain but also in numerous endocrine/neuroendocrine cells as well as in neurons of the peripheral nervous system. The present study investigated the distribution patterns of CART-like immunoreactivity in the pelvic plexus (PP) of the female pig. The co-expression of CART with principal neurotransmitter markers: choline acetyltransferase (ChAT), tyrosine hydroxylase (TH), serotonin (5-HT) or biologically active neuropeptides: pituitary adenylate cyclase-activating polypeptide (PACAP), substance P (SP), calbindin was analyzed using double immunohistochemical stainings. Amongst neurons immunopositive to Hu C/D panneuronal marker as many as 4.1 ± 1.2% in right and 4.4 ± 1.6% in left pelvic ganglia were found to express CART. The vast majority of CART-IR ganglionic neurons were predominantly small in size and were evenly scattered throughout particular ganglia. Immunoreactivity to CART was also detected in numerous nerve terminals (which frequently formed pericellular formations around CART-negative perikarya) as well as in numerous nerve fibres within nerve branches interconnecting the unilateral pelvic ganglia. Immunohistochemistry revealed that virtually all CART-IR neurons were cholinergic in nature and CART-IR basket-like formations frequently encircled TH-positive/CART-negative perikarya. None of CART-IR ganglionic neurons showed immunoreactivity to SP, PACAP, 5-HT or calbindin. CART-IR nerve fibres ran in a close vicinity to serotonin-containing cells or faintly labelled SP-expressing neurons. On the other hand, PACAP-IR, SP-IR (but not 5-HT-positive) nerve terminals were found to run in close proximity to CART-IR neurons. Our results indicate that: 1) CART present in PP may influence the activity of pelvic ganglionic neurons/SIF cells, 2) PP should be considered as a potential source of CART-like supply to pelvic viscera and 3) functional interactions between CART and SP or PACAP are possible at the periphery