The fluorescent pigment lipofuscin accumulates with age in the cytoplasm of cells CNS. Because its broad excitation and emission spectra, presence lipofuscin-like autofluorescence complicates use fluorescence microscopy (e.g., retrograde tract tracing immunocytochemistry). In this study we examined several chemical treatments tissue sections for their ability to reduce or eliminate without adversely affecting other labels. We found that 1-10 mM CuSO 4 50 ammonium acetate buffer (pH 5) 1%...

Neurotransmitters have been shown to coexist in cell bodies, but demonstrating their coexistence within nerve fibers and terminals has more difficult. However, two recent reports outlined a simple light-microscopic method by which neurotransmitters can be terminals. The was identical that used for immunohistochemical localization of one antigen, except primary--secondary antibody systems labeled with different fluorochromes were simultaneously. In the present study, simultaneous...

TWO highly-selective μ-opioid receptor agonists, endomorphin-1 and -2, were recently purified from bovine brain are postulated to be endogenous ligands. We sought determine the effects of these ligands at spinal level in mice. Endomorphin1 -2 produced short acting, naloxone-sensitive antinociception tail flick test inhibited behavior elicited by intrathecally injected substance P. Both anti-allodynic dynorphin-induced allodynia model. Although acute tolerance against both endomorphins...

Antisera were raised against a synthetic peptide corresponding to the carboxyl terminus of kappa-opioid receptor (KOR1). Specificity antisera was verified by staining COS-7 cells transfected with KOR1 and epitope-tagged cDNAs, recognition proteins on Western blots both brain tissue, absence tissue after preabsorption cognate peptide, strong correlation between distribution immunoreactivity that earlier ligand binding in situ hybridization studies. Results indicate neurons is targeted into...

Inhibition of neurons containing gamma-aminobutyric acid (GABA) may underlie some the excitatory effects opioids in central nervous system (CNS). In present study, we examined relationship cloned mu- and delta-opioid receptors (MOR1 DOR1, respectively) to GABAergic brain spinal cord. This was done by combining immunofluorescent staining for MOR1 or DOR1 with that GABA glutamic decarboxylase (GAD); fluorescent retrograde tract-tracing used cases identify particular projections. rats, cells...

We previously demonstrated that the spinal cord κ-opioid receptor (KOR) and μ-opioid (MOR) form heterodimers (KOR/MOR). KOR/MOR formation associated KOR dependency of morphine antinociception are most robust during proestrus. Using Sprague Dawley rats, we now demonstrate (1) synthesis estrogen is critical to these processes, (2) blockade either (ER) α-, β-, or G-protein-coupled ER1 progesterone (PR) substantially reduces eliminates mediation by antinociception. Effects blocking ERs were...

Cell death has been reported in the CNS models of neuropathic pain (Sugimoto et al., 1990; Whiteside and Munglani, 2001; Scholz 2005; Fuccio 2009). In our present study, we examined effects spinal nerve ligation (SNL) on number neurons rostral ventromedial medulla (RVM), a brainstem region involved modulation nociception. rats receiving SNL, found that RVM decreased by 23% side ipsilateral to surgery. The loss was also associated with bilateral increase glia as well activation both...

Opioid-produced antinociception in mammals seems to be mediated part by pathways originating the periaqueductal gray (PAG) and rostroventral medulla (RVM), these may include serotonergic neurons. In present study, we examined relationship of cloned μ- δ-receptors (MOR1 DOR1, respectively) PAG neurons projecting RVM, RVM dorsal spinal cord. This was carried out combining immunocytochemical staining for MOR1, serotonin with fluorescent retrograde tract-tracing. Of 133 retrogradely labeled...

ANTISERA were raised against endomorphin-2, a recently isolated endogenous opioid peptide that binds potently and selectively to the μ-opioid receptor. When sections of spinal cord stained immunocytochemically, dense plexus fibres varicosities was visualized in superficial dorsal horn rats one monkey. Following unilateral multiple rhizotomy, labeling for endomorphin-2 markedly reduced ipsilateral lesion. In both CGRP, double-labeling observed. Taken together, these data suggest occurs small...

The rostral ventromedial medulla (RVM) forms part of a descending pathway that modulates nociceptive neurotransmission at the level spinal cord dorsal horn. However, involvement RVM systems in opioid analgesia are matter some debate. In present study, patch-clamp recordings neurons were made from rats had received retrograde tracer injections into cord. More than 90% identified spinally projecting responded to agonists. Of these neurons, 53% only mu-opioid agonist D-Ala2, N-Me-Phe4, Gly-ol5...

Enhanced glutamatergic neurotransmission in dopamine (DA) neurons of the ventral tegmental area (VTA), triggered by a single cocaine injection, represents an early adaptation linked to more enduring effects abused drugs that characterize addiction. Here, we examined impact vivo exposure on metabotropic inhibitory signaling involving G-protein-gated inwardly rectifying K(+) (Girk) channels VTA DA neurons. Somatodendritic Girk currents evoked GABA(B) receptor (GABA(B)R) agonist baclofen were...

Previous studies have reported that the mRNAs encoding cloned μ-opioid receptor (MOR1) and δ-opioid (DOR1) are expressed in dorsal root ganglia (DRG) of rats. In present study, we determined sizes DRG neurons expressing DOR1 MOR1 examined whether or not were likely to be source immunoreactivity previously observed spinal horn. labeled five male Sprague-Dawley rats by applying Fluoro-Gold (FG) topically entry zone. Five-micrometer cryostat sections cut, situ hybridization was performed using...

The dorsal raphe nucleus (DRN) projects serotonergic axons throughout the brain and is involved in a variety of physiological functions. However, it also includes large population cells that contain other neurotransmitters. To clarify pharmacological differences between nonserotonergic neurons DRN, their postsynaptic responses to 5-hydroxytryptamine (5-HT, serotonin) selective activation 5-HT1A or 5-HT2A/C receptors action potential characteristics were determined using vitro patch-clamp...