Quick Golgi method: Modified for high clarity and better neuronal anatomy.

The Golgi methods have long been used to study the neuronal soma, axons, dendritic arborization and spines. The major concerns of the Golgi method have been its unpredictable nature (inconsistency of impregnation of the stain), time consumed, tissue hardening and clear background, resulting in several modifications to improve the cellular visualization. In the present work we describe a modification of the rapid-Golgi method that takes the benefit of perfusion fixation (with rapid-Golgi solution) then post-fixation in the same fixative for 36 h followed by 36 h impregnation in aqueous AgNO3 followed by vibratomy. This modification is simpler, faster and inexpensive, provides a consistent staining of neurons with good resolution of neuronal soma, dendritic arborization as well as spines with much reduced formation of silver chromate crystals and background in just 3 days.

Differential microglial and astrocytic response to bacterial and viral infection in the developing hippocampus of neonatal rats.

Polyinosinic:polycytidylic acid (Poly I:C; 5 mg/kg body weight, ip) and lipopolysaccharide (LPS; 0.3 mg/kg body weight, ip) induced microglial and astrocytic activation in Sprague Dawley rats. Higher microglial and astrocytic activities were noticed in Poly I:C infused rats throughout the hippocampus till postnatal day 21 with a comparatively weaker response in LPS group. However, LPS induced inflammation persisted even after postnatal day 21, indicating thereby, that the Poly I:C (viral mimic) produces an acute inflammation, while LPS (bacterial endotoxin) produces chronic inflammation when exposed during early neonatal life.

Spirulina platensis protects neurons via suppression of glial activation and peripheral sensitization leading to restoration of motor function in collagen-induced arthritic rats.

Spirulina platensis treatment (400 mg kg-1 for 25 days) effectively suppressed peripheral sensitization via modulation of glial activation and improved motor coordination and restoration of functional motor activity in collagen-induced arthritic rats. Spirulina treatment also resulted in an appreciable reduction of the NF200 accumulation in the spinal cord neurons of arthritic rats. This is indicative of neuroprotective action of S. platensis against glutamate excitotoxicity-induced central sensitization produced by the peripheral joint inflammation in the collagen-induced arthritis. The results suggest that effects of S. platensis may be due to its counter regulation of spinal glial activation and could be a potential strategy for the treatment of arthritis.

Iba1 expressing microglia in the dorsal root ganglia become activated following peripheral nerve injury in rats.

The presence of microglia in dorsal root ganglia (DRG) has not been reported earlier. The dorsal root ganglia contain satellite glial cells (SGCs) and macrophages, which are considered to have infiltrated from the systemic blood. An attempt was made to investigate whether microglia as found in the central nervous system are also present in the dorsal root ganglia of untreated rats and following experimental peripheral nerve injury. Female adult Wistar rats were subjected to sciatic nerve transection injury on the right hand side. The DRGs of the right side were studied with the contralateral DRGs of the left side serving as controls. The tissues, harvested at different time points after injury, following intracardial perfusion fixation, and frozen sections were immunolabeled with anti-GFAP as a marker for SGCs and anti-Iba1 and OX-6 as markers for microglia and activated macrophagic microglia, respectively. These antibodies were also used in combination to ascertain if Iba1+ cells are the SGCs or otherwise and also if macrophagic OX-6+ cells are Iba1 positive microglia. The results indicate that Iba1 positive microglial cells are different from the SGCs in the DRGs. The Iba1 positive microglial cells respond to the sciatic nerve injury becoming activated and macrophagic and express MHCII molecules. Such activated microglia apparently may serve as neurosupportive cells, providing neuroprotection and scavenging cellular debris in response to the injury.

Effects of deltamethrin on granule cell migration during postnatal development of rat cerebellum.

Deltamethrin (DLT; 0.7mg/kg/body wt/day, i.p., dissolved in propylene glycol) administration during postnatal days 913 in Albino rat pups, resulted in a delayed appearance of radial glial fibers, that guide the migration of granule cells. Moreover, the radial glial fibers in the DLT-treated pups were disorganized, hypertrophied and heavily stained. Thus, it is being proposed that although after exposure to DLT the neuronal proliferation occurs at normal rate, the neuronal migration along the stumpy and crumpled radial fibers hamper the journey of the healthy neurons to their proper destination.