geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Tolerance to the cataleptic effect that follows repeated nitric oxide synthase inhibition may be related to functional enzymatic recovery


, : Tolerance to the cataleptic effect that follows repeated nitric oxide synthase inhibition may be related to functional enzymatic recovery. Journal of Psychopharmacology 24(3): 397-405

Systemic or intra-striatal acute administration of nitric oxide synthase (NOS) inhibitors causes catalepsy in rodents. This effect disappears after sub-chronic treatment. The aim of the present study was to investigate if this tolerance is related to changes in the expression of NOS or dopamine-2 (D2) receptor or to a recovery of NOS activity. Male albino Swiss mice (25-30 g) received single or sub-chronic (once a day for 4 days) i.p. injections of saline or L-nitro-arginine (L-NOARG, 40 mg/kg), a non-selective inhibitor of neuronal nitric oxide synthase (nNOS). Twenty-four hours after the last injection, the animals were killed and their brains were removed for immunohistochemistry assay to detect the presence of nNOS or for 'in-situ' hybridisation study using (35)S-labeled oligonucleotide probe complementary to D2 receptor mRNA. The results were analysed by computerised densitometry. Independent groups of animals received the same treatment, but were submitted to the catalepsy test and had their brain removed to measure nitrite and nitrate (NOx) concentrations in the striatum. Acute administration of L-NOARG caused catalepsy that disappeared after sub-chronic treatment. The levels of NOx were significantly reduced after acute L-NOARG treatment. The decrease in NOx after drug injection suffered a partial tolerance after sub-chronic treatment. The catalepsy time after acute or sub-chronic treatment with L-NOARG was negatively (r = -0.717) correlated with NOx levels. Animals that received repeated L-NOARG injections also showed an increase in the number of nNOS-positive neurons in the striatum. No change in D2 receptor mRNA expression was found in the dorsal striatum, nucleus accumbens and substantia nigra. Together, these results suggest that tolerance to L-NOARG cataleptic effects do not depend on changes in D2 receptors. They may depend, however, on plastic changes in nNOS neurons resulting in partial recovery of NO formation in the striatum.

US$19.90

PMID: 18838497

DOI: 10.1177/0269881108097717


Other references

Sastalla, I.; Rosovitz, M.J.; Leppla, S.H., 2011: Accidental selection and intentional restoration of sporulation-deficient Bacillus anthracis mutants. We demonstrate the frequent accidental enrichment of spontaneous sporulation-deficient mutants of Bacillus anthracis on solid medium and identify contributing factors. Mutations in spo0A, encoding the master regulator of sporulation initiation, we...

Hemmingsen, R.; Madsen, A.; Glenthoj, B.; Rubin, P., 1999: Cortical brain dysfunction in early schizophrenia: Secondary pathogenetic hierarchy of neuroplasticity, psychopathology and social impairment. Schizophrenia has the quality of a 'top-down' disorder with perturbation of self, and malattuned appraisal of basic experience of the outside world, and of intentionality. There is dissonance between the faculties of consciousness. The n...

Frankel, F.R.; Tucker, R.W.; Bruce, J.; Stenberg, R., 1978: Fibroblasts and macrophages of mice with the Chediak-Higashi-like syndrome have microtubules and actin cables. Cells of the beige mouse contain abnormally large lysosomes and show enhanced capping of concanavalin A. It has been suggested that these phenomena may be secondary to a defect in microtubule polymerization. We have examined the cytoskeleton of be...

Anonymous, 1999: Medical image transmission tops list of telemedicine applications. Biomedical Instrumentation & Technology 33(4): 299-299

Jacquemyn, H.; Brys, R.; Neubert, M., G., 2005: Fire increases invasive spread of Molinia caerulea mainly through changes in demographic parameters. We investigated the effects of fire on population growth rate and invasive spread-of the perennial tussock grass Molinia caerulea. During the last decades, this species has invaded heathland communities in Western Europe, replacing typical heathla...

Zhao F Y.; Zhang K H.; W.M.J.; Zhou H., 1989: Threshold irradiation dose for damage to dental pulp irradiated by a neodymium yag laser. Dental hypersensitivity is a commonly seen complaint in dental clinics. It is caused by thermal, chemical or mechanical stimulation of exposed dentine, and may be so severe that it affects mastication. Conservative treatments using topically appli...

Norlund, A., 1994: Exercise test at intensive care units--not only advantages. Lakartidningen 91(6): 470, 475-470, 475

Liao, Yuan Xiu; Kuo, Pei Yu; Yang, Ding Yah, 2003: Efficient synthesis of trisubstituted benzopyrano pyrrol-4 -one derivatives from 4-hydroxycoumarin. Various trisubstituted (1)benzopyrano(4,3-b)pyrrol-4(1H)-one derivatives have been synthesized from 4-hydroxycoumarin with a 30-40% yield over six steps. The key step of the synthesis is a base-promoted intramolecular cyclization of enamines 5, fo...

Brown R.C.; Cole K.W., 1970: Sex chromatin and x chromosome replication patterns and incidence of sex chromatin. Federation Proceedings 29(2): 752

Meyer, J.S.; Gotham, J.; Tazaki, Y.; Gotoh, F., 1961: Cardiorespiratory syndrome of extreme obesity with papilledema. Report of a fatal case with electroencepholographic, metabolic, and necropsy studies. Neurology 11: 950-958